HTML Boom reference

This page is an HTML version of the boomref.txt file that was included with the Boom source port. It documents the extended editing facilities that Boom adds for level authors, which today forms a common standard that is supported by most Doom source ports.

I dedicate this page to the memory of James F. Flynn (jff) who authored some parts of it and implemented many of the generalized linedef and sector types which are described below. If you're mapping for Boom, please spare a thought for Jim and the work he did on Boom.

I have deliberately preserved the form of the original text file. The text is from the version of boomref.txt included with Boom 2.02, the last release of Boom. However, it includes an additional section from the MBF version of boomref.txt that documents the type 271 and type 272 linedefs that were added for that port. There's also a separate page with an interactive version of mbfedit.txt that documents the features of that port in more detail.

The document has been reformatted so that most of the text uses a proportional font, for readability. If you prefer to read in the original fixed-width font, click here.

If you prefer, you can just read the original boomref.txt without any of the additions here.

The purpose of this document was originally to be a linkable form of boomref.txt so that I could cross-reference it from the following video of boomedit.wad, a demo WAD that was made to demonstrate most of the main features of Boom. However, the scope has since grown and this document now includes some interactive features - specifically it includes pop-up JavaScript calculators for calculating generalized linedef types. Hopefully these may be of help to level authors creating Boom-compatible WAD files.


Table of Contents


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======================================================================
                        Part I Linedef Types
======================================================================

#######################
Section 0. Terminology
#######################

In BOOM actions are caused to happen thru linedef types. BOOM has three kinds of linedef types:

Regular     - the linedef types that were already in DOOM II v1.9

Extended    - linedef types not in DOOM II v1.9 but less than 8192 
              in value

Generalized - linedef types over 8192 in value that contain bit
              fields that independently control the actions of the sector
              affected.

A linedef with non-zero linedef type is called a linedef trigger. A linedef trigger is always activated in one of three ways - pushing on the first sidedef of the linedef, walking over the linedef, or shooting the linedef with an impact weapon (fists, chainsaw, pistol, shotgun, double barreled, or chaingun).

Linedefs activated by pushing on them come in two varieties. A manual linedef affects the sector on the second sidedef of the line pushed. A switched linedef affects all sectors that have the same tag field as the linedef that was pushed.

Nearly all switched, walkover, and gun linedefs operate on the sectors with the same tag as that in the tag field of the linedef.

Some linedefs are never activated per se, but simply create or control an effect thru their existence and properties, usually affecting the sectors sharing the linedef's tags. There are also a few special case like line-line teleporters and exit linedefs that do not affect sectors.

Some linedefs are only triggerable once, others are triggerable as many times as you like.

Triggering types are denoted by the letters P, S, W, and G for manual(push), switched, walkover, and gun. Their retriggerability is denoted by a 1 or R following the letter. So the triggering types for linedefs are:

P1 PR S1 SR W1 WR G1 GR

Often linedef actions depend on values in neighboring sectors. A neighboring sector is one that shares a linedef in common, just sharing a vertex is not sufficient.

In DOOM only one action on a sector could occur at a time. BOOM supports one floor action, one ceiling action, and one lighting action simultaneously.


################
Section 1. Doors
################

A door is a sector, usually placed between two rooms, whose ceiling raises to open, and lowers to close.

A door is fully closed when its ceiling height is equal to its floor height.

A door is fully open when its ceiling height is 4 less than the lowest neighbor ceiling adjacent to it.

A door may be set to an intermediate state initially, or thru the action of a linedef trigger that affects ceilings or floors. The door is passable to a player when its ceiling is at least 56 units higher than its floor. In general the door is passable to a monster or a thing when its ceiling is at least the monster or thing's height above the floor.

If a door has a ceiling height ABOVE the fully open height, then an open door action moves the ceiling to the fully open height instantly.

If a door has a ceiling height BELOW the fully closed height (that is the ceiling of the door sector is lower than the floor of the door sector) a close door action moves the ceiling to the fully closed height instantly.

--------------------------
Section 1.1 Door functions
--------------------------

Open, Wait, Then Close

On activation, door opens fully, waits a specified period, then closes fully.

Open and Stay Open

On activation, door opens fully and remains there.

Close and Stay Closed

On activation, door closes fully, and remains there.

Close, Wait, Then Open

On activation, door closes fully, waits a specified period, then opens fully.

------------------------------
Section 1.2 Varieties of doors
------------------------------

A door can be triggered by pushing on it, walking over or pressing a linedef trigger tagged to it, or shooting a linedef tagged to it. These are called manual, walkover, switched, or gun doors resp.

Since a push door (P1/PR) has no use for its tag, BOOM has extended the functionality to include changing any tagged sectors to maximum neighbor lighting on fully opening, then to minimum neighbor lighting on fully closing. This is true for regular, extended, and generalized doors with push triggers.

A door trigger can be locked. This means that the door function will only operate if the player is in possession of the right key(s). Regular and extended door triggers only care if the player has a key of the right color, they do not care which. Generalized door triggers can distinguish between skull and card keys, and can also require any key, or all keys in order to activate.

A door can have different speeds, slow, normal, fast or turbo.

A door can wait for different amounts of time.

A door may or may not be activatable by monsters.

Any door function except Close and Stay Closed, when closing and encountering a monster or player's head will bounce harmlessly off that head and return to fully open. A Close and Stay Closed will rest on the head until it leaves the door sector.

------------------------------
Section 1.3 Door linedef types
------------------------------

Regular and Extended Door Types
---------------------------------------------------------------
#        Class   Trig   Lock   Speed    Wait  Monst    Function

1        Reg     PR     No     Slow     4s    Yes      Open, Wait, Then Close
117      Reg     PR     No     Fast     4s    No       Open, Wait, Then Close
63       Reg     SR     No     Slow     4s    No       Open, Wait, Then Close
114      Reg     SR     No     Fast     4s    No       Open, Wait, Then Close
29       Reg     S1     No     Slow     4s    No       Open, Wait, Then Close
111      Reg     S1     No     Fast     4s    No       Open, Wait, Then Close
90       Reg     WR     No     Slow     4s    No       Open, Wait, Then Close
105      Reg     WR     No     Fast     4s    No       Open, Wait, Then Close
4        Reg     W1     No     Slow     4s    No       Open, Wait, Then Close
108      Reg     W1     No     Fast     4s    No       Open, Wait, Then Close

31       Reg     P1     No     Slow     --    No       Open and Stay Open
118      Reg     P1     No     Fast     --    No       Open and Stay Open
61       Reg     SR     No     Slow     --    No       Open and Stay Open
115      Reg     SR     No     Fast     --    No       Open and Stay Open
103      Reg     S1     No     Slow     --    No       Open and Stay Open
112      Reg     S1     No     Fast     --    No       Open and Stay Open
86       Reg     WR     No     Slow     --    No       Open and Stay Open
106      Reg     WR     No     Fast     --    No       Open and Stay Open
2        Reg     W1     No     Slow     --    No       Open and Stay Open
109      Reg     W1     No     Fast     --    No       Open and Stay Open
46       Reg     GR     No     Slow     --    No       Open and Stay Open

42       Reg     SR     No     Slow     --    No       Close and Stay Closed
116      Reg     SR     No     Fast     --    No       Close and Stay Closed
50       Reg     S1     No     Slow     --    No       Close and Stay Closed
113      Reg     S1     No     Fast     --    No       Close and Stay Closed
75       Reg     WR     No     Slow     --    No       Close and Stay Closed
107      Reg     WR     No     Fast     --    No       Close and Stay Closed
3        Reg     W1     No     Slow     --    No       Close and Stay Closed
110      Reg     W1     No     Fast     --    No       Close and Stay Closed

196      Ext     SR     No     Slow     30s   No       Close, Wait, Then Open
175      Ext     S1     No     Slow     30s   No       Close, Wait, Then Open
76       Reg     WR     No     Slow     30s   No       Close, Wait, Then Open
16       Reg     W1     No     Slow     30s   No       Close, Wait, Then Open

Regular and Extended Locked Door Types
---------------------------------------------------------------
#        Class   Trig   Lock   Speed    Wait  Monst    Function

26       Reg     PR     Blue   Slow     4s    No       Open, Wait, Then Close
28       Reg     PR     Red    Slow     4s    No       Open, Wait, Then Close
27       Reg     PR     Yell   Slow     4s    No       Open, Wait, Then Close

32       Reg     P1     Blue   Slow     --    No       Open and Stay Open
33       Reg     P1     Red    Slow     --    No       Open and Stay Open
34       Reg     P1     Yell   Slow     --    No       Open and Stay Open
99       Reg     SR     Blue   Fast     --    No       Open and Stay Open
134      Reg     SR     Red    Fast     --    No       Open and Stay Open
136      Reg     SR     Yell   Fast     --    No       Open and Stay Open
133      Reg     S1     Blue   Fast     --    No       Open and Stay Open
135      Reg     S1     Red    Fast     --    No       Open and Stay Open
137      Reg     S1     Yell   Fast     --    No       Open and Stay Open

There are two generalized door linedef types, Generalized Door, and Generalized Locked Door. The following tables show the possibilities for each parameter, any combination of parameters is allowed:

Slow and Fast represent the same speeds as slow and fast regular doors. Normal is twice as fast as slow, Fast is twice normal, Turbo is twice Fast.

Generalized Door Types
---------------------------------------------------------------
#        Class   Trig   Lock   Speed    Wait  Monst    Function

3C00H-   Gen     P1/PR  No     Slow     1s    Yes      Open, Wait, Then Close
4000H            S1/SR         Normal   4s    No       Open and Stay Open
                 W1/WR         Fast     9s             Close and Stay Closed
                 G1/GR         Turbo    30s            Close, Wait, Then Open

Generalized Locked Door Types
---------------------------------------------------------------
#        Class   Trig   Lock   Speed    Wait  Monst    Function

3800H-   Gen     P1/PR  Any    Slow     1s    No       Open, Wait, Then Close
3C00H            S1/SR  Blue   Normal   4s             Open and Stay Open
                 W1/WR  Red    Fast     9s             Close and Stay Closed
                 G1/GR  Yell   Turbo    30s            Close, Wait, Then Open
                        BlueC
                        RedC
                        YellC
                        BlueS
                        RedS
                        YellS
                        All3
                        All6

#################
Section 2. Floors
#################

----------------------------
Section 2.1 Floor targets
----------------------------

Lowest Neighbor Floor (LnF)

This means that the floor moves to the height of the lowest neighboring floor including the floor itself. If the floor direction is up (only possible with generalized floors) motion is instant, else at the floor's speed.

Next Neighbor Floor (NnF)

This means that the floor moves up to the height of the lowest adjacent floor greater in height than the current, or down to the height of the highest adjacent floor less in height than the current, as determined by the floor's direction. Instant motion is not possible in this case. If no such floor exists, the floor does not move.

Lowest Neighbor Ceiling (LnC)

This means that the floor height changes to the height of the lowest ceiling possessed by any neighboring sector, including that floor's ceiling. If the target height is in the opposite direction to floor motion, motion is instant, otherwise at the floor action's speed.

8 Under Lowest Neighbor Ceiling (8uLnC)

This means that the floor height changes to 8 less than the height of the lowest ceiling possessed by any neighboring sector, including that floor's ceiling. If the target height is in the opposite direction to floor motion, motion is instant, otherwise at the floor action's speed.

Highest Neighbor Floor (HnF)

This means that the floor height changes to the height of the highest neighboring floor, excluding the floor itself. If no neighbor floor exists, the floor moves down to -32000. If the target height is in the opposite direction to floor motion, the motion is instant, otherwise it occurs at the floor action's speed.

8 Above Highest Neighbor Floor (8aHnF)

This means that the floor height changes to 8 above the height of the highest neighboring floor, excluding the floor itself. If no neighbor floor exists, the floor moves down to -31992. If the target height is in the opposite direction to floor motion, the motion is instant, otherwise it occurs at the floor action's speed.

Ceiling

The floor moves up until its at ceiling height, instantly if floor direction is down (only available with generalized types), at the floor speed if the direction is up.

24 Units (24)

The floor moves 24 units in the floor action's direction. Instant motion is not possible with this linedef type.

32 Units (32)

The floor moves 32 units in the floor action's direction. Instant motion is not possible with this linedef type.

512 Units (512)

The floor moves 512 units in the floor action's direction. Instant motion is not possible with this linedef type.

Shortest Lower Texture (SLT)

The floor moves the height of the shortest lower texture on the boundary of the sector, in the floor direction. Instant motion is not possible with this type. In the case that there is no surrounding texture the motion is to -32000 or +32000 depending on direction.

None

Some pure texture type changes are provided for changing the floor texture and/or sector type without moving the floor.

--------------------------------
Section 2.2 Varieties of floors
--------------------------------

A floor can be activated by pushing on a linedef bounding it (generalized types only), or by pushing on a switch with the same tag as the floor sector, or by walking over a linedef with the same tag as the floor, or by shooting a linedef with the same tag as the floor with an impact weapon.

A floor can move either Up or Down.

A floor can move with speeds of Slow, Normal, Fast, or Turbo. If the target height specified by the floor function (see Floor Targets above) is in the opposite direction to the floor's motion, then travel is instantaneous, otherwise its at the speed specified.

A floor action can be a texture change type, in which case after the action the floor texture of the affected floor, and possibly the sector type of the affected floor are changed to those of a model sector. The sector type may be zeroed instead of copied from the model, or not changed at all. These change types are referred to below as Tx (texture only), Tx0 (type zeroed), and TxTy (texture and type changed). The model sector for the change may be the sector on the first sidedef of the trigger (trigger model) or the sector with floor at destination height across the lowest numbered two-sided linedef surrounding the affected sector (numeric model). If no model sector exists, no change occurs. If a change occurs, floor texture is always affected, lighting is never affected, even that corresponding to the sector's type, nor is any other sector property other than the sector's type.

Numeric model algorithm:

1) Find all floors adjacent to the tagged floor at destination height
2) Find the lowest numbered linedef separating those floors from that tagged
3) The sector on the other side of that linedef is the model

A floor action can have the crush property, in which case players and monsters are crushed when the floor tries to move above the point where they fit exactly underneath the ceiling. This means they take damage until they die, leave the sector, or the floor action is stopped. A floor action never reverses on encountering an obstacle, even if the crush property is not true, the floor merely remains in the same position until the obstacle is removed or dies, then continues.

-------------------------------
Section 2.3 Floor linedef types
-------------------------------

Regular and Extended Floor Types
-------------------------------------------------------------------
#     Class   Trig   Dir Spd   Chg  Mdl Mon Crsh  Target

60    Reg     SR     Dn  Slow  None --  No  No    Lowest Neighbor Floor
23    Reg     S1     Dn  Slow  None --  No  No    Lowest Neighbor Floor
82    Reg     WR     Dn  Slow  None --  No  No    Lowest Neighbor Floor
38    Reg     W1     Dn  Slow  None --  No  No    Lowest Neighbor Floor
      
177   Ext     SR     Dn  Slow  TxTy Num No  No    Lowest Neighbor Floor
159   Ext     S1     Dn  Slow  TxTy Num No  No    Lowest Neighbor Floor
84    Reg     WR     Dn  Slow  TxTy Num No  No    Lowest Neighbor Floor
37    Reg     W1     Dn  Slow  TxTy Num No  No    Lowest Neighbor Floor

69    Reg     SR     Up  Slow  None --  No  No    Next Neighbor Floor
18    Reg     S1     Up  Slow  None --  No  No    Next Neighbor Floor
128   Reg     WR     Up  Slow  None --  No  No    Next Neighbor Floor
119   Reg     W1     Up  Slow  None --  No  No    Next Neighbor Floor

132   Reg     SR     Up  Fast  None --  No  No    Next Neighbor Floor
131   Reg     S1     Up  Fast  None --  No  No    Next Neighbor Floor
129   Reg     WR     Up  Fast  None --  No  No    Next Neighbor Floor
130   Reg     W1     Up  Fast  None --  No  No    Next Neighbor Floor

222   Ext     SR     Dn  Slow  None --  No  No    Next Neighbor Floor
221   Ext     S1     Dn  Slow  None --  No  No    Next Neighbor Floor
220   Ext     WR     Dn  Slow  None --  No  No    Next Neighbor Floor
219   Ext     W1     Dn  Slow  None --  No  No    Next Neighbor Floor

64    Reg     SR     Up  Slow  None --  No  No    Lowest Neighbor Ceiling
101   Reg     S1     Up  Slow  None --  No  No    Lowest Neighbor Ceiling
91    Reg     WR     Up  Slow  None --  No  No    Lowest Neighbor Ceiling
5     Reg     W1     Up  Slow  None --  No  No    Lowest Neighbor Ceiling
24    Reg     G1     Up  Slow  None --  No  No    Lowest Neighbor Ceiling

65    Reg     SR     Up  Slow  None --  No  Yes   Lowest Neighbor Ceiling - 8
55    Reg     S1     Up  Slow  None --  No  Yes   Lowest Neighbor Ceiling - 8
94    Reg     WR     Up  Slow  None --  No  Yes   Lowest Neighbor Ceiling - 8
56    Reg     W1     Up  Slow  None --  No  Yes   Lowest Neighbor Ceiling - 8

45    Reg     SR     Dn  Slow  None --  No  No    Highest Neighbor Floor
102   Reg     S1     Dn  Slow  None --  No  No    Highest Neighbor Floor
83    Reg     WR     Dn  Slow  None --  No  No    Highest Neighbor Floor
19    Reg     W1     Dn  Slow  None --  No  No    Highest Neighbor Floor

70    Reg     SR     Dn  Fast  None --  No  No    Highest Neighbor Floor + 8     
71    Reg     S1     Dn  Fast  None --  No  No    Highest Neighbor Floor + 8     
98    Reg     WR     Dn  Fast  None --  No  No    Highest Neighbor Floor + 8     
36    Reg     W1     Dn  Fast  None --  No  No    Highest Neighbor Floor + 8     

180   Ext     SR     Up  Slow  None --  No  No    Absolute 24
161   Ext     S1     Up  Slow  None --  No  No    Absolute 24
92    Reg     WR     Up  Slow  None --  No  No    Absolute 24
58    Reg     W1     Up  Slow  None --  No  No    Absolute 24

179   Ext     SR     Up  Slow  TxTy Trg No  No    Absolute 24
160   Ext     S1     Up  Slow  TxTy Trg No  No    Absolute 24
93    Reg     WR     Up  Slow  TxTy Trg No  No    Absolute 24
59    Reg     W1     Up  Slow  TxTy Trg No  No    Absolute 24

176   Ext     SR     Up  Slow  None --  No  No    Abs Shortest Lower Texture
158   Ext     S1     Up  Slow  None --  No  No    Abs Shortest Lower Texture
96    Reg     WR     Up  Slow  None --  No  No    Abs Shortest Lower Texture
30    Reg     W1     Up  Slow  None --  No  No    Abs Shortest Lower Texture

178   Ext     SR     Up  Slow  None --  No  No    Absolute 512
140   Reg     S1     Up  Slow  None --  No  No    Absolute 512
147   Ext     WR     Up  Slow  None --  No  No    Absolute 512
142   Ext     W1     Up  Slow  None --  No  No    Absolute 512

190   Ext     SR     --  ----  TxTy Trg No  No    None
189   Ext     S1     --  ----  TxTy Trg No  No    None
154   Ext     WR     --  ----  TxTy Trg No  No    None
153   Ext     W1     --  ----  TxTy Trg No  No    None

78    Ext     SR     --  ----  TxTy Num No  No    None
241   Ext     S1     --  ----  TxTy Num No  No    None
240   Ext     WR     --  ----  TxTy Num No  No    None
239   Ext     W1     --  ----  TxTy Num No  No    None

The following tables show the possibilities for generalized floor linedef type parameters. Any combination of parameters is allowed:

Slow and Fast represent the same speeds as slow and fast regular floors. Normal is twice as fast as slow, Fast is twice normal, Turbo is twice Fast.

Generalized Floor Types
---------------------------------------------------------------------------
#      Class   Trig   Dir Spd   *Chg *Mdl Mon Crsh  Target

6000H- Gen     P1/PR  Up  Slow   None Trg Yes Yes   Lowest Neighbor Floor
7FFFH          S1/SR  Dn  Normal Tx   Num No  No    Next Neighbor Floor
               W1/WR      Fast   Tx0                Lowest Neighbor Ceiling
               G1/GR      Turbo  TxTy               Highest Neighbor Floor
                                                    Ceiling
                                                    24
                                                    32
*Mon(ster) enabled must be No if                    Shortest Lower Texture
Chg field is not None

Tx = Texture copied only           Trg = Trigger Model
Tx0 = Texture copied and Type->0   Num = Numeric Model
TxTy = Texture and Type copied


####################
Section 3. Ceilings
####################

----------------------------
Section 3.1 Ceiling Targets
----------------------------

Highest Neighbor Ceiling (HnC)

This means that the ceiling moves to the height of the highest neighboring ceiling NOT including the ceiling itself. If the ceiling direction is down (only possible with generalized ceilings) motion is instant, else at the ceiling's speed. If no adjacent ceiling exists the ceiling moves to -32000 units.

Next Neighbor Ceiling (NnC)

This means that the ceiling moves up to the height of the lowest adjacent ceiling greater in height than the current, or to the height of the highest adjacent ceiling less in height than the current, as determined by the ceiling's direction. Instant motion is not possible in this case. If no such ceiling exists, the ceiling does not move.

Lowest Neighbor Ceiling (LnC)

This means that the ceiling height changes to the height of the lowest ceiling possessed by any neighboring sector, NOT including itself. If the target height is in the opposite direction to ceiling motion, motion is instant, otherwise at the ceiling action's speed. If no adjacent ceiling exists the ceiling moves to 32000 units.

Highest Neighbor Floor (HnF)

This means that the ceiling height changes to the height of the highest neighboring floor, excluding the ceiling's floor itself. If no neighbor floor exists, the ceiling moves down to -32000 or the ceiling's floor, whichever is higher. If the target height is in the opposite direction to ceiling motion, the motion is instant, otherwise it occurs at the ceiling action's speed.

Floor

The ceiling moves down until its at floor height, instantly if ceiling direction is up (only available with generalized types), at the ceiling speed if the direction is down.

8 Above Floor (8aF)

This means that the ceiling height changes to 8 above the height of the ceiling's floor. If the target height is in the opposite direction to ceiling motion, the motion is instant, otherwise it occurs at the ceiling action's speed.

24 Units (24)

The ceiling moves 24 units in the ceiling action's direction. Instant motion is not possible with this linedef type.

32 Units (32)

The ceiling moves 32 units in the ceiling action's direction. Instant motion is not possible with this linedef type.

Shortest Upper Texture (SUT)

The ceiling moves the height of the shortest upper texture on the boundary of the sector, in the ceiling direction. Instant motion is not possible with this type. In the case that there is no surrounding texture the motion is to -32000 or +32000 depending on direction.

----------------------------------
Section 3.2 Varieties of ceilings
----------------------------------

A ceiling can be activated by pushing on a linedef bounding it (generalized types only), or by pushing on a switch with the same tag as the ceiling sector, or by walking over a linedef with the same tag as the ceiling, or by shooting a linedef with the same tag as the ceiling with an impact weapon (generalized types only).

A ceiling can move either Up or Down.

A ceiling can move with speeds of Slow, Normal, Fast, or Turbo. If the target height specified by the ceiling function (see Ceiling Targets above) is in the opposite direction to the ceiling's motion, then travel is instantaneous, otherwise its at the speed specified.

A ceiling action can be a texture change type, in which case after the action the ceiling texture of the affected ceiling, and possibly the sector type of the affected ceiling are changed to those of a model sector. The sector type may be zeroed instead of copied from the model, or not changed at all. These change types are referred to below as Tx (texture only), Tx0 (type set to 0), and TxTy (texture and type copied from model). The model sector for the change may be the sector on the first sidedef of the trigger (trigger model) or the sector with ceiling at destination height across the lowest numbered two-sided linedef surrounding the affected sector (numeric model). If no model sector exists, no change occurs. If a change occurs, ceiling texture is always affected, lighting is never affected, even that corresponding to the sector's type, nor is any other sector property other than the sector's type.

Numeric model algorithm:

1) Find all ceilings adjacent to the tagged ceiling at destination height
2) Find the lowest numbered linedef separating those ceilings from that tagged
3) The sector on the other side of that linedef is the model

A ceiling action can have the crush property (generalized types only), in which case players and monsters are crushed when the ceiling tries to move below the point where they fit exactly underneath the ceiling. This means they take damage until they die, leave the sector, or the ceiling action is stopped. A ceiling action never reverses on encountering an obstacle, even if the crush property is not true, the ceiling merely remains in the same position until the obstacle is removed or dies, then continues.

---------------------------------
Section 3.3 Ceiling linedef types
---------------------------------
Regular and Extended Ceiling Types
-------------------------------------------------------------------
#     Class   Trig   Dir Spd   *Chg *Mdl Mon Crsh Target

43    Reg     SR     Dn  Fast  None  --  No  No   Floor 
41    Reg     S1     Dn  Fast  None  --  No  No   Floor 
152   Ext     WR     Dn  Fast  None  --  No  No   Floor 
145   Ext     W1     Dn  Fast  None  --  No  No   Floor 

186   Ext     SR     Up  Slow  None  --  No  No   Highest Neighbor Ceiling
166   Ext     S1     Up  Slow  None  --  No  No   Highest Neighbor Ceiling
151   Ext     WR     Up  Slow  None  --  No  No   Highest Neighbor Ceiling
40    Reg     W1     Up  Slow  None  --  No  No   Highest Neighbor Ceiling

187   Ext     SR     Dn  Slow  None  --  No  No   8 Above Floor
167   Ext     S1     Dn  Slow  None  --  No  No   8 Above Floor
72    Reg     WR     Dn  Slow  None  --  No  No   8 Above Floor
44    Reg     W1     Dn  Slow  None  --  No  No   8 Above Floor

205   Ext     SR     Dn  Slow  None  --  No  No   Lowest Neighbor Ceiling
203   Ext     S1     Dn  Slow  None  --  No  No   Lowest Neighbor Ceiling
201   Ext     WR     Dn  Slow  None  --  No  No   Lowest Neighbor Ceiling
199   Ext     W1     Dn  Slow  None  --  No  No   Lowest Neighbor Ceiling

206   Ext     SR     Dn  Slow  None  --  No  No   Highest Neighbor Floor
204   Ext     S1     Dn  Slow  None  --  No  No   Highest Neighbor Floor
202   Ext     WR     Dn  Slow  None  --  No  No   Highest Neighbor Floor
200   Ext     W1     Dn  Slow  None  --  No  No   Highest Neighbor Floor
Generalized Ceiling Types
---------------------------------------------------------------------------
#      Class   Trig   Dir Spd   *Chg *Mdl Mon Crsh  Target

4000H- Gen     P1/PR  Up  Slow   None Trg Yes Yes   Highest Neighbor Ceiling
5FFFH          S1/SR  Dn  Normal Tx   Num No  No    Next Neighbor Ceiling
               W1/WR      Fast   Tx0                Lowest Neighbor Ceiling
               G1/GR      Turbo  TxTy               Highest Neighbor Floor
                                                    Floor
                                                    24
                                                    32
*Mon(ster) enabled must be No if                    Shortest Upper Texture
Chg field is not None

Tx = Texture copied only           Trg = Trigger Model
Tx0 = Texture copied and Type->0   Num = Numeric Model
TxTy = Texture and Type copied

############################
Section 4. Platforms (Lifts)
############################

A platform is basically a floor action involving two heights. The simple raise platform actions, for example, differ from the corresponding floor actions in that if they encounter an obstacle, they reverse direction and return to their former height.

The most often used kind of platform is a lift which travels from its current height to the target height, then waits a specified time and returns to it former height.

-----------------------------
Section 4.1 Platform Targets
-----------------------------

Lowest Neighbor Floor

This means that the platforms "low" height is the height of the lowest surrounding floor, including the platform itself. The "high" height is the original height of the floor.

Next Lowest Neighbor Floor

This means that the platforms "low" height is the height of the highest surrounding floor lower than the floor itself. If no lower floor exists, no motion occurs as the "low" and "high" heights are then both equal to the floors current height.

Lowest Neighbor Ceiling

This means that the platforms "low" height is the height of the lowest surrounding ceiling unless this is higher than the floor itself. If no adjacent ceiling exists, or is higher than the floor no motion occurs as the "low" and "high" heights are then both equal to the floors current height.

Lowest and Highest Floor

This target sets the "low" height to the lowest neighboring floor, including the floor itself, and the "high" height to the highest neighboring floor, including the floor itself. When this target is used the floor moves perpetually between the two heights. Once triggered this type of linedef runs permanently, even if the motion is temporarily suspended with a Stop type. No other floor action can be commanded on the sector after this type is begun.

Ceiling

This target sets the "high" height to the ceiling of the sector and the "low" height to the floor height of the sector and is only used in the instant toggle type that switches the floor between the ceiling and its original height on each activation. This is also the ONLY instant platform type.

Raise Next Floor

This means that the "high" height is the lowest surrounding floor higher than the platform. If no higher adjacent floor exists no motion will occur.

Raise 24 Units

The "low" height is the original floor height, the "high" height is 24 more.

Raise 32 Units

The "low" height is the original floor height, the "high" height is 32 more.

-----------------------------------
Section 4.2 Varieties of Platforms
-----------------------------------

A platform can be activated by pushing on a linedef bounding it (generalized types only), or by pushing on a switch with the same tag as the platform sector, or by walking over a linedef with the same tag as the platform, or by shooting a linedef with the same tag as the platform with an impact weapon.

A platform can move with speeds of Slow, Normal, Fast, or Turbo. Only the instant toggle platform moves instantly, all others move at the platform's speed.

A platform can have a delay, in between when it reaches "high" height and returns to "low" height, or at both ends of the motion in the case of perpetual lifts.

A platform action can be a texture change type, in which case after the action the floor texture of the affected floor, and possibly the sector type of the affected floor are changed to those of a model sector. The sector type may be zeroed instead of copied from the model, or not changed at all. These change types are referred to below as Tx (texture only), Tx0 (type zeroed), and TxTy (texture and type changed). The model sector for the change is always the sector on the first sidedef of the trigger (trigger model). If a change occurs, floor texture is always affected, lighting is never affected, even that corresponding to the sector's type, nor is any other sector property other than the sector's type.

-----------------------------------
Section 4.3 Platform Linedef types
-----------------------------------

Regular and Extended Platform Types
-------------------------------------------------------------------
#     Class  Trig   Dly Spd  Chg  Mdl Mon Target

66    Reg    SR     --  Slow Tx   Trg No  Raise 24 Units
15    Reg    S1     --  Slow Tx   Trg No  Raise 24 Units
148   Ext    WR     --  Slow Tx   Trg No  Raise 24 Units
143   Ext    W1     --  Slow Tx   Trg No  Raise 24 Units

67    Reg    SR     --  Slow Tx0  Trg No  Raise 32 Units
14    Reg    S1     --  Slow Tx0  Trg No  Raise 32 Units
149   Ext    WR     --  Slow Tx0  Trg No  Raise 32 Units
144   Ext    W1     --  Slow Tx0  Trg No  Raise 32 Units

68    Reg    SR     --  Slow Tx0  Trg No  Raise Next Floor
20    Reg    S1     --  Slow Tx0  Trg No  Raise Next Floor
95    Reg    WR     --  Slow Tx0  Trg No  Raise Next Floor
22    Reg    W1     --  Slow Tx0  Trg No  Raise Next Floor
47    Reg    G1     --  Slow Tx0  Trg No  Raise Next Floor

181   Ext    SR     3s  Slow None --  No  Lowest and Highest Floor (perpetual)
162   Ext    S1     3s  Slow None --  No  Lowest and Highest Floor (perpetual)
87    Reg    WR     3s  Slow None --  No  Lowest and Highest Floor (perpetual)
53    Reg    W1     3s  Slow None --  No  Lowest and Highest Floor (perpetual)

182   Ext    SR     --  ---- ---- --  --  Stop
163   Ext    S1     --  ---- ---- --  --  Stop
89    Reg    WR     --  ---- ---- --  --  Stop
54    Reg    W1     --  ---- ---- --  --  Stop

62    Reg    SR     3s  Slow None --  No  Lowest Neighbor Floor (lift)
21    Reg    S1     3s  Slow None --  No  Lowest Neighbor Floor (lift)
88    Reg    WR     3s  Slow None --  No  Lowest Neighbor Floor (lift)
10    Reg    W1     3s  Slow None --  No  Lowest Neighbor Floor (lift)

123   Reg    SR     3s  Fast None --  No  Lowest Neighbor Floor (lift)
122   Reg    S1     3s  Fast None --  No  Lowest Neighbor Floor (lift)
120   Reg    WR     3s  Fast None --  No  Lowest Neighbor Floor (lift)
121   Reg    W1     3s  Fast None --  No  Lowest Neighbor Floor (lift)

211   Ext    SR     --  Inst None --  No  Ceiling (toggle)
212   Ext    WR     --  Inst None --  No  Ceiling (toggle)
Generalized Lift Types
---------------------------------------------------------------------------
#      Class   Trig   Dly Spd    Mon  Target

3400H- Gen     P1/PR  1s  Slow   Yes  Lowest Neighbor Floor
37FFH          S1/SR  3s  Normal No   Next Lowest Neighbor Floor
               W1/WR  5s  Fast        Lowest Neighbor Ceiling
               G1/GR  10s Turbo       Lowest and Highest Floor (perpetual)

############################
Section 5. Crusher Ceilings
############################

A crusher ceiling is a linedef type that causes the ceiling to cycle between its starting height and 8 above the floor, damaging monsters and players that happen to be in between. Barrels explode when crushed.

Once a crusher ceiling is started it remains running for the remainder of the level even if temporarily suspended with a stop type. No other ceiling action can be used in that sector thereafter.

----------------------------------
Section 5.1 Varieties of Crushers
----------------------------------

A crusher can be activated by pushing on a linedef bounding it (generalized types only), or by pushing on a switch with the same tag as the crusher sector, or by walking over a linedef with the same tag as the crusher, or by shooting a linedef with the same tag as the crusher with an impact weapon (generalized types only).

A crusher has a speed: slow, normal, fast, or turbo. The slower the speed, the more damage the crusher does when crushing, simply thru being applied longer. When a slow or normal crusher is moving down and encounters something to crush, it slows down even more, by a factor of 8. This persists until it reaches bottom of stroke and starts up again. Fast and turbo crushers do not slow down.

A crusher can be silent. The regular silent crusher makes platform stop and start noises at top and bottom of stroke. The generalized silent crusher is completely quiet.

A crusher linedef is provided to stop a crusher in its current position. Care should be used that this doesn't lock the player out of an area of the wad if the crusher is too low to pass. A crusher can be restarted, but not changed, with any crusher linedef.

----------------------------------
Section 5.2 Crusher Linedef Types
----------------------------------

Regular and Extended Crusher Types
-------------------------------------------------------------------
#     Class  Trig   Spd  Mon Silent Action

184   Ext    SR     Slow No  No     Start
49    Reg    S1     Slow No  No     Start
73    Reg    WR     Slow No  No     Start
25    Reg    W1     Slow No  No     Start

183   Ext    SR     Fast No  No     Start
164   Ext    S1     Fast No  No     Start
77    Reg    WR     Fast No  No     Start
6     Reg    W1     Fast No  No     Start

185   Ext    SR     Slow No  Yes    Start
165   Ext    S1     Slow No  Yes    Start
150   Ext    WR     Slow No  Yes    Start
141   Reg    W1     Slow No  Yes    Start

188   Ext    SR     ---- --  --     Stop
168   Ext    S1     ---- --  --     Stop
74,   Reg    WR     ---- --  --     Stop
57,   Reg    W1     ---- --  --     Stop
Generalized Crusher Types
---------------------------------------------------------------------------
#      Class   Trig   Spd    Mon  Silent

2F80H- Gen     P1/PR  Slow   Yes  Yes
2FFFH          S1/SR  Normal No   No
               W1/WR  Fast        
               G1/GR  Turbo       

##########################
Section 6. Stair Builders
##########################

A stair builder is a linedef type that sets a sequence of sectors defined by a complex rule to an ascending or descending sequence of heights.

The rule for stair building is as follows:

1) The first step to rise or fall is the tagged sector. It rises or falls by the stair stepsize, at the stair speed, in the stair direction..

2) To find the next step (sector) affected examine each two-sided linedef with first sidedef facing into the previous step in numerical order. For each such linedef if the sector on the other side is already active, or has already risen from this stair, the linedef is skipped. If textures are not ignored then any linedef with a different floor texture on its second side is also skipped. The next step to rise is the sector on the other side of the first linedef not skipped. If none exists, stair building ceases.

The next step moves to the height of the previous step plus or minus the stepsize depending on the direction the stairs build, up or down. If the motion is in the same direction as the stairs build, it occurs at stair build speed, otherwise it is instant.

3) Repeat step 2 until stair building ceases.

----------------------------------------
Section 6.1 Varieties of Stair Builders
----------------------------------------

A stair can be activated by pushing on a linedef bounding it (generalized types only), or by pushing on a switch with the same tag as the stair sector, or by walking over a linedef with the same tag as the stair, or by shooting a linedef with the same tag as the stair with an impact weapon (generalized types only).

Only extended and generalized stair types are retriggerable. The extended retriggerable stairs are mostly useless, though triggering a stair with stepsize 8 twice might be used. The generalized retriggerable stairs alternate building up and down on each activation which is much more useful.

A stair can build up or down (generalized types only).

A stair can have a step size of 4, 8, 16, or 24. Only generalized types support stepsize of 4 or 24.

A stair can have build speeds of slow, normal, fast or turbo. Only generalized types support speeds of normal or turbo.

A stair can stop on encountering a different texture or ignore (generalized types only) different textures and continue.

Only the regular build fast, stepsize 16 stair has the property that monsters and players can be crushed by the motion, all others do not crush.

----------------------------------------------------
Section 6.2 Regular and Extended Stair Builder Types
----------------------------------------------------

Regular and Extended Stairs Types
-------------------------------------------------------------------
#     Class  Trig  Dir Spd   Step Ignore Mon

258   Ext    SR    Up  Slow  8    No     No
7     Reg    S1    Up  Slow  8    No     No
256   Ext    WR    Up  Slow  8    No     No
8     Reg    W1    Up  Slow  8    No     No

259   Ext    SR    Up  Fast  16   No     No
127   Reg    S1    Up  Fast  16   No     No
257   Ext    WR    Up  Fast  16   No     No
100   Reg    W1    Up  Fast  16   No     No
Generalized Stairs Types
---------------------------------------------------------------------------
#      Class   Trig   Dir Spd     Step  Ignore Mon

3000H- Gen     P1/PR  Up  Slow    4     Yes    Yes
33FFH          S1/SR  Dn  Normal  8     No     No 
               W1/WR      Fast    16 
               G1/GR      Turbo   24 

####################
Section 7 Elevators
####################

An elevator is a linedef type that moves both floor and ceiling together. All elevator linedefs are extended, there are no regular or generalized elevator types. Instant elevator motion is not possible, and monsters cannot activate elevators. All elevator triggers are either switched or walkover.

-----------------------------
Section 7.1 Elevator Targets
-----------------------------

Next Highest Floor

The elevator floor moves to the lowest adjacent floor higher than the elevator's floor, the ceiling staying the same height above the floor. If there is no higher floor the elevator doesn't move.

Next Lowest Floor

The elevator floor moves to the highest adjacent floor lower than the current floor, the ceiling staying the same height above the floor. If there is no lower floor the elevator doesn't move.

Current Floor

The elevator floor moves to the height of the floor on the first sidedef of the triggering line, the ceiling remaining the same height above the elevator floor.

-----------------------------------
Section 7.2 Elevator Linedef Types
-----------------------------------
Extended Elevator types
-------------------------------------------------------------------
#     Class  Trig  Spd    Target

230   Ext    SR    Fast   Next Highest Floor
229   Ext    S1    Fast   Next Highest Floor
228   Ext    WR    Fast   Next Highest Floor
227   Ext    W1    Fast   Next Highest Floor

234   Ext    SR    Fast   Next Lowest Floor
233   Ext    S1    Fast   Next Lowest Floor
232   Ext    WR    Fast   Next Lowest Floor
231   Ext    W1    Fast   Next Lowest Floor

238   Ext    SR    Fast   Current Floor
237   Ext    S1    Fast   Current Floor
236   Ext    WR    Fast   Current Floor
235   Ext    W1    Fast   Current Floor

###################
Section 7 Lighting
###################

The lighting linedef types change the lighting in the tagged sector. All are regular or extended types, there are no generalized lighting types. All are switched or walkovers.

-----------------------------
Section 7.1 Lighting Targets
-----------------------------

Lights to Minimum Neighbor

Each tagged sector is set to the minimum light level found in any adjacent sector. The tagged sectors are changed in numerical order, and this may influence the result.

Lights to Maximum Neighbor

Each tagged sector is set to the maximum light level found in any adjacent sector. The tagged sectors are changed in numerical order, and this may influence the result.

Blinking

Each tagged sector begins blinking between two light levels. The brighter level is the light level in the tagged sector. The darker level is the minimum neighbor light level, or 0 if all neighbor sectors have lighting greater than or equal to the sector's at the time of activation. The blinking is non-synchronous, beginning 1-9 gametics after activation, with a dark period of 1 sec (35 gametics) and a bright period of 1/7 sec (5 gametics).

35 Units

Each tagged sector is set to a light level of 35 units.

255 Units

Each tagged sector is set to a light level of 255 units.

-----------------------------------
Section 7.2 Lighting Linedef Types
-----------------------------------

Regular and Extended Lighting types
-------------------------------------------------------------------
#     Class  Trig  Target

139   Reg    SR    35 Units
170   Ext    S1    35 Units
79    Reg    WR    35 Units
35    Reg    W1    35 Units

138   Reg    SR    255 Units
171   Ext    S1    255 Units
81    Reg    WR    255 Units
13    Reg    W1    255 Units

192   Ext    SR    Maximum Neighbor
169   Ext    S1    Maximum Neighbor
80    Reg    WR    Maximum Neighbor
12    Reg    W1    Maximum Neighbor

194   Ext    SR    Minimum Neighbor
173   Ext    S1    Minimum Neighbor
157   Ext    WR    Minimum Neighbor
104   Reg    W1    Minimum Neighbor

193   Ext    SR    Blinking
172   Ext    S1    Blinking
156   Ext    WR    Blinking
17    Reg    W1    Blinking

################
Section 8 Exits
################

An exit linedef type ends the current level bringing up the intermission screen with its report of kills/items/secrets or frags in the case of deathmatch. Obviously, none are retriggerable, and none require tags, since no sector is affected.

---------------------------
Section 8.1 Exit Varieties
---------------------------

An exit can be activated by pushing on a switch with the exit type or by walking over a linedef with the exit type, or by shooting a linedef with the exit type with an impact weapon.

An exit can be normal or secret. The normal exit simply ends the level and takes you to the next level via the intermission screen. A secret exit only works in a special level depending on the IWAD being played. In DOOM the secret exits can be on E1M3, E2M5, or E3M6. In DOOM II they can be in levels 15 and 31. If a secret exit is used in any other level, it brings you back to the start of the current level. In DOOM the secret exits go from E1M3 to E1M9, E2M5 to E2M9, and E3M6 to E3M9. In DOOM II they go from 15 to 31 and from 31 to 32. In DOOM II a normal exit from 31 or 32 goes to level 16.

-----------------------------------
Section 8.2 Exit Linedef Types
-----------------------------------

Regular and Extended Exit types
-------------------------------------------------------------------
#     Class  Trig  Type

11    Reg    S1    Normal
52    Reg    W1    Normal
197   Ext    G1    Normal

51    Reg    S1    Secret
124   Reg    W1    Secret
198   Ext    G1    Secret

######################
Section 9 Teleporters
######################

A teleporter is a linedef that when crossed or switched makes the player or monster appear elsewhere in the level. There are only regular and extended teleporters, no generalized teleporters exist (yet). Teleporters are the only direction sensitive walkover triggers in DOOM (to allow them to be exited without teleporting again). They must be crossed from the first sidedef side in order to work.

The place that the player or monster appears is set in one of two ways. The more common is by a teleport thing in the sector tagged to the teleport line. The newer completely player preserving line-line silent teleport makes the player appear relative to the exit line (identified by having the same tag as the entry line) with the same orientation, position, momentum and height that they had relative to the entry line just before teleportation. A special kind of line-line teleporter is also provided that reverses the player's orientation by 180 degrees.

In the case of several lines tagged the same as the teleport line, or several sectors tagged the same, or several teleport things in the tagged sector, in all cases the lowest numbered one is used.

In DOOM crossing a W1 teleport line in the wrong direction used it up, and it was never activatable. In BOOM this is not the case, it does not teleport but remains active until next crossed in the right direction.

If the exit of a teleporter is blocked a monster (or anything besides a player) will not teleport thru it. However if the exit of teleporter is blocked a player will, including into a down crusher, a monster, or another player. In the latter two cases the monster/player occupying the spot dies messily, and this is called a telefrag.

-------------------------------
Section 9.1 Teleport Varieties
-------------------------------

A teleporter can be walkover or switched, and retriggerable or not.

A teleporter can have destination set by a teleport thing in the tagged sector, or by a line tagged the same as the teleport line. These are called thing teleporters and line teleporters resp.

A teleporter can preserve orientation or set orientation from the position, height, and angle of the teleport thing. Note a thing destination teleporter always sets position, though it may preserve orientation otherwise.

A teleporter can produce green fog and a whoosh noise, or it can be silent, in which case it does neither.

A teleporter can transport monsters only, or both players and monsters.

-----------------------------------
Section 9.2 Teleport Linedef types
-----------------------------------

Regular and Extended Teleport types
-------------------------------------------------------------------
#     Class  Trig  Silent Mon Plyr Orient    Dest

195   Ext    SR    No     Yes Yes  Set       TP thing in tagged sector
174   Ext    S1    No     Yes Yes  Set       TP thing in tagged sector
97    Reg    WR    No     Yes Yes  Set       TP thing in tagged sector
39    Reg    W1    No     Yes Yes  Set       TP thing in tagged sector

126   Reg    WR    No     Yes No   Set       TP thing in tagged sector
125   Reg    W1    No     Yes No   Set       TP thing in tagged sector
269   Ext    WR    Yes    Yes No   Set       TP thing in tagged sector
268   Ext    W1    Yes    Yes No   Set       TP thing in tagged sector

210   Ext    SR    Yes    Yes Yes  Preserve  TP thing in tagged sector
209   Ext    S1    Yes    Yes Yes  Preserve  TP thing in tagged sector
208   Ext    WR    Yes    Yes Yes  Preserve  TP thing in tagged sector
207   Ext    W1    Yes    Yes Yes  Preserve  TP thing in tagged sector

244   Ext    WR    Yes    Yes Yes  Preserve  Line with same tag
243   Ext    W1    Yes    Yes Yes  Preserve  Line with same tag
263   Ext    WR    Yes    Yes Yes  Preserve  Line with same tag (reversed)
262   Ext    W1    Yes    Yes Yes  Preserve  Line with same tag (reversed)

267   Ext    WR    Yes    Yes No   Preserve  Line with same tag 
266   Ext    W1    Yes    Yes No   Preserve  Line with same tag 
265   Ext    WR    Yes    Yes No   Preserve  Line with same tag (reversed) 
264   Ext    W1    Yes    Yes No   Preserve  Line with same tag (reversed)

##################
Section 10 Donuts
##################

A donut is a very specialized linedef type that lowers a pillar in a surrounding pool, while raising the pool and changing its texture and type.

The tagged sector is the pillar, and its lowest numbered line must be two-sided. The sector on the other side of that is the pool. The pool must have a two-sided line whose second sidedef does not adjoin the pillar, and the sector on the second side of the lowest numbered such linedef is the model for the pool's texture change. The model sector floor also provides the destination height both for lowering the pillar and raising the pool.

No generalized donut linedefs exist, and all are switched or walkover.

---------------------------------
Section 10.1 Donut Linedef types
---------------------------------
Regular and Extended Donut types
-------------------------------------------------------------------
#     Class  Trig

191   Ext    SR
9     Reg    S1
155   Ext    WR
146   Ext    W1

#############################
Section 11 Property Transfer
#############################

These linedefs are special purpose and are used to transfer properties from the linedef itself or the sector on its first sidedef to the tagged sector(s). None are triggered, they simply exist.

Extended Property Transfer Linedefs
-------------------------------------------------------------------
#     Class  Trig Description

213   Ext --   Set Tagged Floor Lighting to Lighting on 1st Sidedef's Sector

Used to give the floor of a sector a different light level from the remainder of the sector. For example bright lava in a dark room.

261   Ext --   Set Tagged Ceiling Lighting to Lighting on 1st Sidedef's Sector

Used to give the ceiling of a sector a different light level from the remainder of the sector.

260   Ext --   Make Tagged Lines (or this line if tag==0) Translucent

Used to make 2s normal textures translucent. If tag==0, then this linedef's normal texture is made translucent if it's 2s, and the default translucency map TRANMAP is used as the filter. If tag!=0, then all similarly-tagged 2s linedefs' normal textures are made translucent, and if this linedef's first sidedef contains a valid lump name for its middle texture (as opposed to a texture name), and the lump is 64K long, then that lump will be used as the translucency filter instead of the default TRANMAP, allowing different filters to be used in different parts of the same maps. If the first side's normal texture is not a valid translucency filter lump name, it must be a valid texture name, and will be displayed as such on this linedef.

242   Ext --   Set Tagged Lighting, Flats Heights to 1st Sidedef's Sector,
               and set colormap based on sidedef textures.

This allows the tagged sector to have two levels -- an actual floor and ceiling, and another floor or ceiling where more flats are rendered. Things will stand on the actual floor or hang from the actual ceiling, while this function provides another rendered floor and ceiling at the heights of the sector on the first sidedef of the linedef. Typical use is "deep water" that can be over the player's head.

     ----------------------------------  < real sector's ceiling height
    |         real ceiling             | < control sector's ceiling texture
    |                                  |
    |                                  | < control sector's lightlevel
    |              A                   |
    |                                  | < upper texture as colormap
    |                                  |
    |                                  | < control sector's floor texture
     ----------------------------------  < control sector's ceiling height
    |         fake ceiling             | < real sector's ceiling texture
    |                                  |
    |                                  | < real sector's lightlevel
    |              B                   |
    |                                  | < normal texture as colormap
    |                                  |
    |          fake floor              | < real sector's floor texture
     ----------------------------------  < control sector's floor height
    |                                  | < control sector's ceiling texture
    |                                  |
    |                                  | < control sector's lightlevel
    |              C                   |
    |                                  | < lower texture as colormap
    |                                  |
    |          real floor              | < control sector's floor texture
     ----------------------------------  < real sector's floor height

Boom sectors controlled by a 242 linedef are partitioned into 3 spaces. The viewer's xyz coordinates uniquely determine which space they are in.

If they are in space B (normal space), then the floor and ceiling textures and lightlevel from the real sector are used, and the colormap from the 242 linedef's first sidedef's normal texture is used (COLORMAP is used if it's invalid or missing). The floor and ceiling are rendered at the control sector's heights.

If they are in space C ("underwater"), then the floor and ceiling textures and lightlevel from the control sector are used, and the lower texture in the 242 linedef's first sidedef is used as the colormap.

If they are in space A ("head over ceiling"), then the floor and ceiling textures and lightlevel from the control sector are used, and the upper texture in the 242 linedef's first sidedef is used as the colormap.

If only two of these adjacent partitions in z-space are used, such as underwater and normal space, one has complete control over floor textures, ceiling textures, light level, and colormaps, in each of the two partitions. The control sector determines the textures and lighting in the more "unusual" case (e.g. underwater).

It's also possible for the fake floor to extend below the real floor, in which case an invisible platform / stair effect is created. In that case, the picture looks like this (barring any ceiling effects too):

     ----------------------------------  < real sector's ceiling texture
    |   real ceiling = fake ceiling    |
    |                                  |
    |                                  |
    |              B                   | < real sector's lightlevel
    |                                  | < normal texture's colormap
    |                                  |
    |          real floor              |
     ----------------------------------  < invisible, no texture drawn
    |                                  |
    |                                  |
    |                                  | < real sector's lightlevel
    |              C                   | < normal texture's colormap
    |                                  |
    |                                  |
    |          fake floor              | < real sector's floor texture
     ----------------------------------  < fake sector's floor height

In this case, since the viewer is always at or above the fake floor, no colormap/lighting/texture changes occur -- the fake floor just gets drawn at the control sector's height, but at the real sector's lighting and texture, while objects stand on the higher height of the real floor.

It's the viewer's position relative to the fake floor and/or fake ceiling, which determines whether the control sector's lighting and textures should be used, and which colormap should be used. If the viewer is always between the fake floor and fake ceiling, then no colormap, lighting, or texture changes occur, and the view just sees the real sector's textures and light level drawn at possibly different heights.

If the viewer is below the fake floor height set by the control sector, or is above the fake ceiling height set by the control sector, then the corresponding colormap is used (lower or upper texture name), and the textures and lighting are taken from the control sector rather than the real sector. They are still stacked vertically in standard order -- the control sector's ceiling is always drawn above the viewer, and the control sector's floor is always drawn below the viewer.

The kaleidescope effect only occurs when F_SKY1 is used as the control sector's floor or ceiling. If F_SKY1 is used as the control sector's ceiling texture, then under water, only the control sector's floor appears, but it "envelops" the viewer. Similarly, if F_SKY1 is used as the control sector's floor texture, then when the player's head is over a fake ceiling, the control sector's ceiling is used throughout.

F_SKY1 causes HOM when used as a fake ceiling between the viewer and normal space. Since there is no other good use for it, this kaleidescope is an option turned on by F_SKY1. Note that this does not preclude the use of sky REAL ceilings over deep water -- this is the control sector's ceiling, the one displayed when the viewer is underwater, not the real one.

A colormap has the same size and format as Doom's COLORMAP. Extra colormaps may defined in Boom by adding them between C_START and C_END markers in wads. Colormaps between C_START and C_END are automatically merged by Boom with any previously defined colormaps.

WATERMAP is a colormap predefined by Boom which can be used to provide a blue-green tint while the player is under water. WATERMAP can be modified by pwads.

Ceiling bleeding may occur if required upper textures are not used.

223   Ext --   Length Sets Friction in tagged Sector,Sludge<100, Ice>100

The length of the linedef with type 223 controls the amount of friction experienced by the player in the tagged sector, when in contact with the floor. Lengths less than 100 are sticker than normal, lengths greater than 100 are slipperier than normal. The effect is only present in the tagged sector when its friction enable bit (bit 8) in the sector type is set. This allows the flat to be changed in conjunction with turning the effect on or off thru texture/type changes.

271   Ext --   Transfer sky texture to tagged sectors 
272   Ext --   Transfer sky texture to tagged sectors, flipped

These linedefs transfer wall textures to skies. F_SKY1 must still be used as the floor or ceiling texture in the sectors for which sky is desired, but the presence of a 271 or 272 property-transfer linedef can change the sky texture to something other than a level-based default.

Every sector with F_SKY1 floor or ceiling which shares the same sector tag as the 271 or 272 linedef will use a sky texture based on the upper texture of the first sidedef in the 271 or 272 linedef. Sectors with F_SKY1 floors or ceilings which are not tagged with 271 or 272 linedefs, behave just like Doom.

Horizontal offsets or scrolling in the transferred texture, is converted into rotation of the sky texture. Vertical offsets or scrolling is transferred as well, allowing for precise adjustments of sky position. Unpegging in the sky transfer linedef does not affect the sky texture.

Horizontal scrolling of the transferred upper wall texture is converted into rotation of the sky texture, but it occurs at a very slow speed relative to the moving texture, allowing for long-period rotations (such as one complete revolution per Doom real-time hour).

Effects other than sky-transfer effects are not excluded from the affected sector(s), and tags can be shared so long as the effects are unambiguous. For example, a wall-scrolling linedef can share a sector tag with both its affectee linedef (the one being scrolled), and with the sector that the latter controls. There is no ambiguity because one effect (scrolling) applies to a linedef, while the other effect (sky transfer) applies to a sector.

If a sector underneath a special sky needs to be set up to have a different purpose (for example, if it is a lift or a stairbuilder), then two tags will need to be created, and the transfer linedef and any scrolling linedefs will need to be duplicated as well, so that the same effect as far as the sky goes, is duplicated in two separate sector tags. This will not affect sky appearance, but it will allow a special sector which needs a unique tag, to sit under such a sky.

Animated textures may be transferred to skies as well.

In Doom, skies were flipped horizontally. To maintain compatibility with this practice, the 272 linedef flips the wall image horizontally. The 271 linedef does not flip the wall image, and it is intended to make it easier to take existing non-flipped wall textures and transfer them to skies.

Sky textures which are different must be separated by non-sky textures, or else the results are undefined.


Constant pushers
----------------

Two types of constant pushers are available, wind and current. Depending on whether you are above, on, or below (special water sectors) the ground level, the amount of force varies.

The length of the linedef defines the 'full' magnitude of the force, and the linedef's angle defines the direction.

     line type         above  on   under
     ---------         -----  --   -----
     wind       224    full  half  none
     current    225    none  full  full

The linedef should be tagged to the sector where you want the effect. The special type of the sector should have bit 9 set (0x200). If this bit is turned off, the effect goes away. For example, a fan creating a wind could be turned off, and the wind dies, by changing the sector type and clearing that bit.

Constant pushers can be combined with scrolling effects and point pushers.

224  Ext  --   Length/Direction Sets Wind Force in tagged Sectors


225  Ext  --   Length/Direction Sets Current Force in tagged Sectors
Point pushers
-------------

Two types of point pushers are available, push and pull.

The previous implementation of these was SECTOR-SPECIFIC. The new implementation ignores sector boundaries and provides the effect in a circular area whose center is defined by a Thing of type 5001 (push) or 5002 (pull). You now also don't have to set any option flags on these Things. A new linedef type of 226 is used to control the effect, and this line should be tagged to the sector with the 5001/5002 Thing.

The length of the linedef defines the 'full' magnitude of the force, and the force is inversely proportional to distance from the point source. If the length of the controlling linedef is L, then the force is reduced to zero at a distance of 2L.

The angle of the controlling linedef is not used.

The sector where the 5001/5002 Things reside must have bit 9 set (0x200) in its type. If this is turned off, the effect goes away.

Point pushers can be combined with scrolling effects and constant pushers.

226  Ext  --   Length Sets Point Source Wind/Current Force in Tagged Sectors

###########################################
Section 12 Scrolling Walls, Flats, Objects
###########################################

Static Scrollers

The most basic kind of scrolling linedef causes some part of the tagged sector or tagged wall to scroll, in proportion to the length of the linedef the trigger is on, and according to the direction that trigger linedef lies. For each 32 units of length of the trigger, the tagged object scrolls 1 unit per frame. Since the length of a linedef doesn't change during gameplay, these types are static, the scrolling effect remains constant during gameplay. However, these effects can be combined with, and/or canceled by, other scrollers.


250    -- Scroll Tagged Ceiling

The ceiling of the tagged sector scrolls in the direction of the linedef trigger, 1 unit per frame for each 32 units of linedef trigger length. Objects attached to the ceiling do not move.


251    -- Scroll Tagged Floor                                 

The floor of the tagged sector scrolls in the direction of the linedef trigger, 1 unit per frame for each 32 units of linedef trigger length. Objects resting on the floor do not move.


252    -- Carry Objects on Tagged Floor                       

Objects on the floor of the tagged sector move in the direction of the linedef trigger, 1 unit per frame for each 32 units of linedef trigger length. The floor itself does not scroll.


253    -- Scroll Tagged Floor, Carry Objects

Both the floor of the tagged sector and objects resting on that floor move in the direction of the linedef trigger, 1 unit per frame for each 32 units of linedef trigger length.


254    -- Scroll Tagged Wall, Same as Floor/Ceiling

Walls with the same tag as the linedef trigger scroll at the same rate as a floor or ceiling controlled by one of 250-253, allowing their motion to be synchronized. When the linedef trigger is not parallel to the wall, the component of the linedef in the direction perpendicular to the wall causes the wall to scroll vertically. The length of the component parallel to the wall sets the horizontal scroll rate, the length of the component perpendicular to the wall sets the vertical scroll rate.


Simple Static Scrollers

For convenience three simpler static scroll functions are provided for when you just need a wall to scroll and don't need to control its rate and don't want to bother with proportionality.

255    -- Scroll Wall Using Sidedef Offsets                   

For simplicity, a static scroller is provided that scrolls the first sidedef of a linedef, based on its x- and y- offsets. No tag is used. The x offset controls the rate of horizontal scrolling, 1 unit per frame per x offset, and the y offset controls the rate of vertical scrolling, 1 unit per frame per y offset.

48     -- Animated wall, Scrolls Left                         

A linedef with this type scrolls its first sidedef left at a constant rate of 1 unit per frame.

85     -- Animated wall, Scrolls Right

A linedef with this type scrolls its first sidedef right at a constant rate of 1 unit per frame.


Dynamic Scrolling

To achieve dynamic scrolling effects, the position or rate of scrolling is controlled by the relative position of the floor and ceiling of the sector on the scrolling trigger's first sidedef. The direction of scrolling remains controlled by the direction of the linedef trigger. Either the floor or ceiling may move in the controlling sector, or both. The control variable is the amount of change in the sum of the floor and ceiling heights.

All scroll effects are additive, and thus two or more effects may reinforce and/or cancel each other.

Displacement Scrollers

In the first kind, displacement scrolling, the position of the scrolled objects or walls changes proportionally to the motion of the floor or ceiling in the sector on the first sidedef of the scrolling trigger. The proportionality is set by the length of the linedef trigger. If it is 32 units long, the wall, floor, ceiling, or object moves 1 unit for each unit the floor or ceiling of the controlling sector moves. If it is 64 long, they move 2 units per unit of relative floor/ceiling motion in the controlling sector and so on.

245    -- Scroll Tagged Ceiling w.r.t. 1st Side's Sector 

The tagged sector's ceiling texture scrolls in the direction of the scrolling trigger line, when the sector on the trigger's first sidedef changes height. The amount moved is the height change times the trigger length, divided by 32. Objects attached to the ceiling do not move.


246    -- Scroll Tagged Floor w.r.t. 1st Side's Sector        

The tagged sector's floor texture scrolls in the direction of the scrolling trigger line when the sector on the trigger's first sidedef changes height. The amount moved is the height change times the trigger length, divided by 32. Objects on the floor do not move.


247    -- Push Objects on Tagged Floor wrt 1st Side's Sector  

Objects on the tagged sector's floor move in the direction of the scrolling trigger line when the sector on the trigger's first sidedef changes height. The amount moved is the height change times the trigger length, divided by 32.


248    -- Push Objects & Tagged Floor wrt 1st Side's Sector   

The tagged sector's floor texture, and objects on the floor, move in the direction of the scrolling trigger line when the sector on the trigger's first sidedef changes height. The amount moved is the height change times the trigger length, divided by 32.


249    -- Scroll Tagged Wall w.r.t 1st Side's Sector          

Walls with the same tag as the linedef trigger scroll at the same rate as a floor or ceiling controlled by one of 245-249, allowing their motion to be synchronized. When the linedef trigger is not parallel to the wall, the component of the linedef in the direction perpendicular to the wall causes the wall to scroll vertically. The length of the component parallel to the wall sets the horizontal scroll displacement, the length of the component perpendicular to the wall sets the vertical scroll displacement. The distance scrolled is the controlling sector's height change times the trigger length, divided by 32.


Accelerative Scrollers

The second kind of dynamic scrollers, accelerative scrollers, also react to height changes in the sector on the first sidedef of the linedef trigger, but the RATE of scrolling changes, not the displacement. That is, changing the controlling sector's height speeds up or slows down the scrolling by the change in height times the trigger's length, divided by 32.

An on/off scroller can be made by using an accelerative scroller and any linedef that changes the controlling sector's heights. If a scroll effect which is initially on is desired, then the accelerative scroller should be combined with a static one which turns the scroll effect on initially. The accelerative scroller would then need to be set up to cancel the static scroller's effect when the controlling sector's height changes.


214    -- Accel Tagged Ceiling w.r.t. 1st Side's Sector

The tagged sector's ceiling's rate of scroll changes in the direction of the trigger linedef (use vector addition if already scrolling) by the change in height of the sector on the trigger's first sidedef times the length of the linedef trigger, divided by 32. For example, if the ceiling is motionless originally, the linedef trigger is 32 long, and the ceiling of the controlling sector moves 1 unit, the tagged ceiling will start scrolling at 1 unit per frame.


215    -- Accel Tagged Floor w.r.t. 1st Side's Sector         

The tagged sector's floor's rate of scroll changes in the direction of the trigger linedef (use vector addition if already scrolling) by the change in height of the sector on the trigger's first sidedef times the length of the linedef trigger, divided by 32. For example, if the floor is motionless originally, the linedef trigger is 32 long, and the ceiling of the controlling sector moves 1 unit, the tagged floor will start scrolling at 1 unit per frame.


216    -- Accel Objects on Tagged Floor wrt 1st Side's Sector 

Objects on the tagged sector's floor's rate of motion changes in the direction of the trigger linedef (use vector addition if already moving) by the change in height of the sector on the trigger's first sidedef times the length of the linedef trigger divided by 32. For example, if the objects are motionless originally, the linedef trigger is 32 long, and the ceiling of the controlling sector moves 1 unit, the objects on the tagged floor will start moving at 1 unit per frame.


217    -- Accel Objects&Tagged Floor wrt 1st Side's Sector    

The tagged sector's floor, and objects on it, change its rate of motion in the direction of the trigger linedef (use vector addition if already moving) by the change in height of the sector on the trigger's first sidedef times the length of the linedef trigger, divided by 32. For example, if the floor and objects are motionless originally, the linedef trigger is 32 long, and the ceiling of the controlling sector moves 1 unit, the objects and the tagged floor will start moving at 1 unit per frame.


218    -- Accel Tagged Wall w.r.t 1st Side's Sector           

Walls with the same tag as the linedef trigger increase their scroll rate in sync with a floor or ceiling controlled by one of 214-217. When the linedef trigger is not parallel to the wall, the component of the linedef in the direction perpendicular to the wall causes the wall to increase its vertical scroll rate. The length of the component parallel to the wall sets the change in horizontal scroll rate, the length of the component perpendicular to the wall sets the change in vertical scroll rate. The rate change is the height change times the trigger length, divided by 32.


======================================================================

#######################################################
Section 13 Detailed Generalized Linedef Specification
#######################################################

BOOM has added generalized linedef types that permit the parameters of linedef actions to be nearly independently chosen.

To support these, DETH has been modified to support them via dialogs for each generalized type; each dialog allows the parameters for that type to be independently specified by choice from a array of radio buttons. A parser has also been added to support reading back the function of a generalized linedef from its type number.

NOTE to wad authors:

This requires a lot of type numbers, 20608 in all so far. Some editors may object to the presence of these new types thru assuming that a lookup table of size 256 suffices (or some other reason). For those that must continue to use such an editor, it may be necessary to stick to the old linedef types, which are still present.

We are also providing command line tools to set these linedef types, independent of which editor you happen to use, but they are a lot less slick, and more difficult to use than DETH. See TRIGCALC.EXE and CLED.EXE in the EDITUTIL.ZIP package of the BOOM distribution.

== Generalized Linedef Ranges =======================================

There are types for Floors, Ceilings, Doors, Locked Doors, Lifts, Stairs, and Crushers. The allocation of linedef type field numbers is according to the following table:

Type            Start      Length   (Dec)
-----------------------------------------------------------------
Floors          0x6000     0x2000  (8192)
Ceilings        0x4000     0x2000  (8192)
Doors           0x3c00     0x0400  (1024)
Locked Doors    0x3800     0x0400  (1024)
Lifts           0x3400     0x0400  (1024)
Stairs          0x3000     0x0400  (1024)
Crushers        0x2F80     0x0080   (128)
-----------------------------------------------------------------
Totals:  0x2f80-0x7fff     0x5080  (20608)

======================================================================

The following sections define the placement and meaning of the bit fields within each linedef category. Fields in the description are listed in increasing numeric order.

Some nomenclature:

Target height designations:

H means highest, L means lowest, N means next, F means floor, C means ceiling, n means neighbor, Cr means crush, sT means shortest lower texture.

Texture change designations:

c0n change texture, change sector type to 0, numeric model change c0t change texture, change sector type to 0, trigger model change cTn change texture only, numeric model change cTt change texture only, trigger model change cSn change texture and sector type to model's, numeric model change cSt change texture and sector type to model's, trigger model change

A trigger model change uses the sector on the first side of the trigger for its model. A numeric model change looks at the sectors adjoining the tagged sector at the target height, and chooses the one across the lowest numbered two sided line for its model. If no model exists, no change occurs. Note that in DOOM II v1.9, no model meant an illegal sector type was generated.


------------------------------------------------------------------
generalized floors (8192 types)

field   description                       NBits   Mask     Shift
------------------------------------------------------------------

trigger W1/WR/S1/SR/G1/GR/D1/DR            3     0x0007      0
speed   slow/normal/fast/turbo             2     0x0018      3
model   trig/numeric -or- nomonst/monst    1     0x0020      5
direct  down/up                            1     0x0040      6
target  HnF/LnF/NnF/LnC/C/sT/24/32         3     0x0380      7
change  nochg/zero/txtonly/type            2     0x0c00      10
crush   no/yes                             1     0x1000      12

DETH Nomenclature:

W1[m] F->HnF DnS [c0t] [Cr]
WR[m] F->LnF DnN [c0n] 
S1[m] F->NnF DnF [cTt]  
SR[m] F->LnC DnT [cTn]          
G1[m] F->C   UpS [cSt]          
GR[m] FbysT  UpN [cSn]          
D1[m] Fby24  UpF                        
DR[m] Fby32  UpT                        

Notes:

1) When change is nochg, model is 1 when monsters can activate trigger
   otherwise monsters cannot activate it.
2) The change fields mean the following:
   nochg   - means no texture change or type change
   zero    - means sector type is zeroed, texture copied from model
   txtonly - means sector type unchanged, texture copied from model
   type    - means sector type and floor texture are copied from model
3) down/up specifies the "normal" direction for moving. If the
   target specifies motion in the opposite direction, motion is instant.
   Otherwise it occurs at speed specified by speed field.
4) Speed is 1/2/4/8 units per tic
5) If change is nonzero then model determines which sector is copied.
   If model is 0 its the sector on the first side of the trigger.
   if model is 1 (numeric) then the model sector is the sector at
   destination height on the opposite side of the lowest numbered
   two sided linedef around the tagged sector. If it doesn't exist
   no change occurs.
------------------------------------------------------------------
generalized ceilings (8192 types)

field   description                        NBits   Mask     Shift
------------------------------------------------------------------

trigger W1/WR/S1/SR/G1/GR/D1/DR             3     0x0007      0
speed   slow/normal/fast/turbo              2     0x0018      3
model   trig/numeric -or- nomonst/monst     1     0x0020      5
direct  down/up                             1     0x0040      6
target  HnC/LnC/NnC/HnF/F/sT/24/32          3     0x0380      7
change  nochg/zero/txtonly/type             2     0x0c00      10
crush   no/yes                              1     0x1000      12

DETH Nomenclature:

W1[m] C->HnC DnS [Cr] [c0t] 
WR[m] C->LnC DnN      [c0n] 
S1[m] C->NnC DnF      [cTt] 
SR[m] C->HnF DnT      [cTn]     
G1[m] C->F   UpS      [cSt]     
GR[m] CbysT  UpN      [cSn]     
D1[m] Cby24  UpF                        
DR[m] Cby32  UpT                        

Notes:

1) When change is nochg, model is 1 when monsters can activate trigger
   otherwise monsters cannot activate it.
2) The change fields mean the following:
   nochg   - means no texture change or type change
   zero    - means sector type is zeroed, texture copied from model
   txtonly - means sector type unchanged, texture copied from model
   type    - means sector type and ceiling texture are copied from model
3) down/up specifies the "normal" direction for moving. If the
   target specifies motion in the opposite direction, motion is instant.
   Otherwise it occurs at speed specified by speed field.
4) Speed is 1/2/4/8 units per tic
5) If change is nonzero then model determines which sector is copied.
   If model is 0 its the sector on the first side of the trigger.
   if model is 1 (numeric) then the model sector is the sector at
   destination height on the opposite side of the lowest numbered
   two sided linedef around the tagged sector. If it doesn't exist
   no change occurs.
------------------------------------------------------------------
generalized doors (1024 types)

field   description                       NBits    Mask     Shift
------------------------------------------------------------------

trigger W1/WR/S1/SR/G1/GR/D1/DR            3      0x0007      0
speed   slow/normal/fast/turbo             2      0x0018      3
kind    odc/o/cdo/c                        2      0x0060      5
monster n/y                                1      0x0080      7
delay   1/4/9/30 (secs)                    2      0x0300      8

DETH Nomenclature:

W1[m] OpnD{1|4|9|30}Cls S
WR[m] Opn               N
S1[m] ClsD{1|4|9|30}Opn F
SR[m] Cls               T
G1[m]
GR[m]
D1[m]
DR[m]

Notes:

1) The odc (Open, Delay, Close) and cdo (Close, Delay, Open) kinds use
   the delay field. The o (Open and Stay) and c (Close and Stay) kinds 
   do not.
2) The precise delay timings in gametics are: 35/150/300/1050
3) Speed is 2/4/8/16 units per tic
------------------------------------------------------------------
generalized locked doors (1024 types)

field   description                       NBits    Mask     Shift
------------------------------------------------------------------

trigger W1/WR/S1/SR/G1/GR/D1/DR            3      0x0007      0
speed   slow/normal/fast/turbo             2      0x0018      3
kind    odc/o                              1      0x0020      5
lock    any/rc/bc/yc/rs/bs/ys/all          3      0x01c0      6
sk=ck   n/y                                1      0x0200      9

DETH Nomenclature:

W1[m] OpnDCls           S Any
WR[m] Opn               N R{C|S|K}
S1[m]                   F B{C|S|K}
SR[m]                   T Y{C|S|K}
G1[m]                     All{3|6}
GR[m]
D1[m]
DR[m]

Notes:

1) Delay for odc kind is constant at 150 gametics or about 4.333 secs
2) The lock field allows any key to open a door, or a specific key to
   open a door, or all keys to open a door.
3) If the sk=ck field is 0 (n) skull and cards are different keys,
   otherwise they are treated identically. Hence an "all" type door
   requires 3 keys if sk=ck is 1, and 6 keys if sk=ck is 0.
4) Speed is 2/4/8/16 units per tic
-------------------------------------------------------------------
generalized lifts (1024 types)

field   description                       NBits    Mask     Shift
-------------------------------------------------------------------

trigger W1/WR/S1/SR/G1/GR/D1/DR            3      0x0007      0
speed   slow/normal/fast/turbo             2      0x0018      3
monster n/y                                1      0x0020      5
delay   1/3/5/10 (secs)                    2      0x00c0      6
target  LnF/NnF/LnC/LnF<->HnF(perp.)       2      0x0300      8

DETH Nomenclature:

W1[m] Lft  F->LnFD{1|3|5|10}    S
WR[m]      F->NnFD{1|3|5|10}    N
S1[m]      F->LnCD{1|3|5|10}    F
SR[m]      HnF<->LnFD{1|3|5|10} T
G1[m]
GR[m]
D1[m]
DR[m]

Notes:

1) The precise delay timings in gametics are: 35/105/165/350
2) Speed is 1/2/4/8 units per tic
3) If the target specified is above starting floor height, or does not
   exist the lift does not move when triggered. NnF is Next Lowest
   Neighbor Floor.
4) Starting a perpetual lift between lowest and highest neighboring floors
   locks out all other floor actions on the sector, even if it is stopped
   with the non-extended stop perpetual floor function.
-------------------------------------------------------------------
generalized stairs (1024 types)

field   description                       NBits    Mask     Shift
-------------------------------------------------------------------

trigger W1/WR/S1/SR/G1/GR/D1/DR            3      0x0007      0
speed   slow/normal/fast/turbo             2      0x0018      3
monster n/y                                1      0x0020      5
step    4/8/16/24                          2      0x00c0      6
dir     dn/up                              1      0x0100      8
igntxt  n/y                                1      0x0200      9

DETH Nomenclature:

W1[m] Stair Dn s4  S [Ign]
WR[m]       Up s8  N
S1[m]          s16 F
SR[m]          s24 T
G1[m]
GR[m]
D1[m]
DR[m]

Notes:

1) Speed is .25/.5/2/4 units per tic
2) If igntxt is 1, then the staircase will not stop building when
   a step does not have the same texture as the previous.
3) A retriggerable stairs builds up and down alternately on each
   trigger.
-------------------------------------------------------------------
generalized crushers (128 types)

field   description                       NBits    Mask     Shift
-------------------------------------------------------------------

trigger W1/WR/S1/SR/G1/GR/D1/DR            3      0x0007      0
speed   slow/normal/fast/turbo             2      0x0018      3
monster n/y                                1      0x0020      5
silent  n/y                                1      0x0040      6

DETH Nomenclature:

W1[m] Crusher S [Silent]
WR[m]         N
S1[m]         F
SR[m]         T
G1[m]
GR[m]
D1[m]
DR[m]

Notes:

1) Speed is 1/2/4/8 units per second, faster means slower damage as usual.
2) If silent is 1, the crusher is totally quiet, no start/stop sounds


======================================================================
                        Part II Sector Types
======================================================================

BOOM is backward compatible with DOOM's sector types. All types 0-17 have the same meaning they did under DOOM. Types 18-31 are reserved for extended sector types, that work like DOOM's and share the limitation that only one type can be active in a sector at once. No extended sector types are implemented at this time.

####################################
Section 14. Regular Sector types
####################################

From Matt Fell's Unofficial DOOM Spec the DOOM sector types are:

Dec Hex Class   Description
-------------------------------------------------------------------
 0  00  -       Normal, no special characteristic.
 1  01  Light   random off
 2  02  Light   blink 0.5 second
 3  03  Light   blink 1.0 second
 4  04  Both    -10/20% health AND light blink 0.5 second
 5  05  Damage  -5/10% health
 7  07  Damage  -2/5% health
 8  08  Light   oscillates
 9  09  Secret  a player must stand in this sector to get credit for
                  finding this secret. This is for the SECRETS ratio
                  on inter-level screens.
10  0a  Door    30 seconds after level start, ceiling closes like a door.
11  0b  End     -10/20% health. If a player's health is lowered to less
                  than 11% while standing here, then the level ends! Play
                  proceeds to the next level. If it is a final level
                  (levels 8 in DOOM 1, level 30 in DOOM 2), the game ends!
12  0c  Light   blink 0.5 second, synchronized
13  0d  Light   blink 1.0 second, synchronized
14  0e  Door    300 seconds after level start, ceiling opens like a door.
16  10  Damage  -10/20% health

17  11  Light   flickers on and off randomly

Note that BOOM will NEVER exit the game on an illegal sector type, as was the case with DOOM. The sector type will merely be ignored.

####################################
Section 15. Generalized sector types
####################################

BOOM also provides generalized sector types, based on bit fields, that allow several sector type properties to be independently specified for a sector. Texture change linedefs can be used to switch some or all of these properties dynamically, outside lighting.

Bits 0 thru 4 specify the lighting type in the sector, the same codes that DOOM used are employed:

Dec Bits 4-0   Description
-------------------------------------------------------------------
0   00000      Normal lighting
1   00001      random off
2   00010      blink 0.5 second
3   00011      blink 1.0 second
4   00100      -10/20% health AND light blink 0.5 second
8   01000      oscillates
12  01100      blink 0.5 second, synchronized
13  01101      blink 1.0 second, synchronized
17  10001      flickers on and off randomly

Bits 5 and 6 set the damage type of the sector, with the usual 5/10/20 damage units per second.

Dec Bits 6-5   Description
-------------------------------------------------------------------
0   00         No damage
32  01         5  units damage per sec (halve damage in TYTD skill)
64  10         10 units damage per sec
96  11         20 units damage per sec

Bit 7 makes the sector count towards the secrets total at game end

Dec Bit 7      Description
-------------------------------------------------------------------
0    0         Sector is not secret
128  1         Sector is secret

Bit 8 enables the ice/mud effect controlled by linedef 223

Dec Bit 8      Description
-------------------------------------------------------------------
0    0         Sector friction disabled
256  1         Sector friction enabled

Bit 9 enables the wind effects controlled by linedefs 224-226

Dec Bit 9      Description
-------------------------------------------------------------------
0    0         Sector wind disabled
512  1         Sector wind enabled

Bits 10 and 11 are not implemented yet, but are reserved for use in sound control. Bit 10 will suppress all sounds within the sector, while bit 11 will disable any sounds due to floor or ceiling motion by the sector.

======================================================================
                        Part III Linedef Flags
======================================================================

Only one new linedef flag is implemented, called PassThru, which allows a push or switch linedef trigger to pass the push action thru it to ones within range behind it. In this way BOOM is capable of setting off many actions with a single push. Note that the limitation of one floor action, one ceiling action, and one lighting action per sector affected still applies however.

The new linedef flag is bit 9, value 512, in the linedef flags word.

======================================================================
                        Part IV Thing Flags
======================================================================

BOOM has implemented two new thing flags, "not in DM" and "not in COOP", which in combination with the existing "not in Single" flag, usually called "Multiplayer", allow complete control over a level's inventory and monsters, in any game mode.

If you want a thing to be only available in Single play, you set both the "not in DM" and "not in COOP" flags. Other combinations are similar.

"not in DM"   is bit 5, value 32, in the thing flags word.
"not in COOP" is bit 6, value 64, in the thing flags word.
======================================================================
                        Part V Thing Types
======================================================================

BOOM has implemented two new thing types as well, MT_PUSH (5001), and MT_PULL(5002). These control the origin of the point source wind effect controlled by linedef types 225 and 226, and set whether the wind blows towards or away from the origin depending on which is used.

======================================================================
                        Part VI BOOM Predefined Lumps
======================================================================

BOOM supports resources embedded in the .EXE that are loaded before all other resources. They can be replaced by resources of the same name in the IWAD or add-on PWADs. These resources can be extracted into a wad thru use of the command:

BOOM -dumplumps predef.wad

You can then extract the resources from predef.wad to alter them for replacement purposes.

Menu text
---------
M_HORSEN       Mouse horizontal sensitivity menu
M_VERSEN       Mouse vertical sensitivity menu
M_SETUP        Setup menu entry in main menu
M_KEYBND       Key Bindings entry in setup menu
M_AUTO         Automap entry in setup menu
M_CHAT         Chat string entry in setup menu
M_ENEM         Enemies options entry in setup menu
M_STAT         Status bar and Hud entry in setup menu
M_WEAP         Weapons entry in setup menu
M_MESS         Message option entry in setup menu
M_COLORS       Palette color picker diagram
M_PALNO        Xed-out symbol for unused automap features
M_BUTT1        Setup reset button off state
M_BUTT2        Setup reset button on state

Font chars
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STCFN096       ` character for standard DOOM font
STBR123        HUD font bargraph char, full, 4 vertical bars
STBR124        HUD font bargraph char, partial, 3 vertical bars
STBR125        HUD font bargraph char, partial, 2 vertical bars
STBR126        HUD font bargraph char, partial, 1 vertical bars
STBR127        HUD font bargraph char, empty, 0 vertical bars

DIG0         HUD font 0 char
DIG1         HUD font 1 char
DIG2         HUD font 2 char
DIG3         HUD font 3 char
DIG4         HUD font 4 char
DIG5         HUD font 5 char
DIG6         HUD font 6 char
DIG7         HUD font 7 char
DIG8         HUD font 8 char
DIG9         HUD font 9 char
DIGA         HUD font A char
DIGB         HUD font B char
DIGC         HUD font C char
DIGD         HUD font D char
DIGE         HUD font E char
DIGF         HUD font F char
DIGG         HUD font G char
DIGH         HUD font H char
DIGI         HUD font I char
DIGJ         HUD font J char
DIGK         HUD font K char
DIGL         HUD font L char
DIGM         HUD font M char
DIGN         HUD font N char
DIGO         HUD font O char
DIGP         HUD font P char
DIGQ         HUD font Q char
DIGR         HUD font R char
DIGS         HUD font S char
DIGT         HUD font T char
DIGU         HUD font U char
DIGV         HUD font V char
DIGW         HUD font W char
DIGX         HUD font X char
DIGY         HUD font Y char
DIGZ         HUD font Z char
DIG45        HUD font - char
DIG47        HUD font / char
DIG58        HUD font : char
DIG91        HUD font [ char
DIG93        HUD font ] char

Status bar
----------
STKEYS6        Both blue keys graphic
STKEYS7        Both yellow keys graphic
STKEYS8        Both red keys graphic
Box chars
---------
BOXUL        Upper left corner of box
BOXUC        Center of upper border of box
BOXUR        Upper right corner of box
BOXCL        Center of left border of box
BOXCC        Center of box
BOXCR        Center of right border of box
BOXLL        Lower left corner of box
BOXLC        Center of lower border of box
BOXLR        Lower right corner of box

Lumps missing in v1.1
---------------------
STTMINUS       minus sign for neg frags in status bar
WIMINUS        minus sign for neg frags on end screen
M_NMARE        nightmare skill menu string
STBAR          status bar background
DSGETPOW       sound for obtaining power-up
Text end screen
---------------
ENDBOOM        Text displayed at end of game, 80X25 with attributes

Sprites
-------
TNT1A0         Invisible sprite for push/pull controller things

Switches and Animations
-----------------------
SWITCHES       Definition of switch textures recognized
ANIMATED       Definition of animated textures and flats recognized

SWITCHES format:

The SWITCHES lump makes the names of the switch textures used in the game known to the engine. It consists of a list of records each 20 bytes long, terminated by an entry (not used) whose last 2 bytes are 0.

9 bytes        Null terminated string naming "off" state texture for switch
9 bytes        Null terminated string naming "on" state texture for switch
2 bytes        Short integer for the IWADs switch will work in
                1=shareware
                2=registered/retail DOOM or shareware
                3=DOOM II, registered/retail DOOM, or shareware
                0=terminates list of known switches

ANIMATED format:

The ANIMATED lump makes the names of the animated flats and textures known to the engine. It consists of a list of records, each 23 bytes long, terminated by a record (not used) whose first byte is -1 (255).

1 byte         -1 to terminate list, 0 if a flat, 1 if a texture
9 bytes        Null terminated string naming last texture/flat in animation
9 bytes        Null terminated string naming first texture/flat in animation
4 bytes        Animation speed, number of frames between animation changes

The utility package contains a program, SWANTBLS.EXE that will generate both the SWITCHES and ANIMATED lumps from a text file. An example is provided, DEFSWANI.DAT that generates the standard set of switches and animations for DOOM.

Colormaps
---------
WATERMAP       Custom greenish colormap for underwater use

The WATERMAP lump has the same format as COLORMAP, 34 tables of 256 bytes each, see the UDS for details. Note that colormaps you add to a PWAD must be between C_START and C_END markers.

The utility package contains a program, CMAPTOOL.EXE, that will generate custom colormaps for use with BOOM. It also includes 7 premade colormaps, and an add-on wad containing them.


Color translation tables
------------------------
CRBRICK        Translates red range to brick red
CRTAN          Translates red range to tan
CRGRAY         Translates red range to gray
CRGREEN        Translates red range to green
CRBROWN        Translates red range to brown
CRGOLD         Translates red range to dark yellow
CRRED          Translates red range to red range (no change)
CRBLUE         Translates red range to light blue
CRBLUE2        Translates red range to dark blue (status bar numerals)
CRORANGE       Translates red range to orange
CRYELLOW       Translates red range to light yellow

These tables are used to translate the red font characters to other colors. They are made replaceable in order to support custom palettes in TC's better. Note however that the font character graphics must be defined using the palette indices for the standard red range of the palette 176-191.

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