Linedef
From ZDoom Wiki
Linedefs are what make up the 'shape' (for lack of a better word) of your map. Every linedef is between two vertices and contains one or two sidedefs (which contain texture data). There are two major purposes of linedefs. The first is to give your map a definitive boundary between the player and the void (any area of a map behind a 1s linedef is considered void space), and the second is to trigger action specials.
Linedefs can be assigned any of the Action Specials and will trigger them when a specified action occurs. You may flag linedefs to have their special executed when the player walks over the line, when the player uses the line (switches) or when the player pushes the line (similar to Quake or Quake 2 switches). Monsters may also trigger specials by walking over the line, and finally a projectile impact or cross can also trigger a special if you so desire.
Contents |
Specification (Doom Format)
| Bytes | Data Type | Description | Notes |
| 0-1 | Unsigned Short | Beginning Vertex | |
| 2-3 | Unsigned Short | Ending Vertex | |
| 4-5 | Unsigned Short | Flags | |
| 6-7 | Unsigned Short | Special action | |
| 8-9 | Unsigned Short | Sector tag | |
| 10-11 | Unsigned Short | Right Sidedef | 0xFFFF means there is no sidedef |
| 12-13 | Unsigned Short | Left Sidedef | 0xFFFF means there is no sidedef |
Specification (Hexen Format)
| Bytes | Data Type | Description | Notes |
| 0-1 | Unsigned Short | Beginning Vertex | |
| 2-3 | Unsigned Short | Ending Vertex | |
| 4-5 | Unsigned Short | Flags | |
| 6 | Unsigned Byte | Special action | |
| 7 | Unsigned Byte | Action argument 1 | |
| 8 | Unsigned Byte | Action argument 2 | |
| 9 | Unsigned Byte | Action argument 3 | |
| 10 | Unsigned Byte | Action argument 4 | |
| 11 | Unsigned Byte | Action argument 5 | |
| 12-13 | Unsigned Short | Right sidedef | 0xFFFF means there is no sidedef |
| 14-15 | Unsigned Short | Left sidedef | 0xFFFF means there is no sidedef |
Linedef Flags
| Bit |
Hex |
Description |
ZDoom/Hexen ONLY |
| 0 |
0x0001 |
blocks players and monsters |
|
| 1 |
0x0002 |
blocks monsters |
|
| 2 |
0x0004 |
two sided |
|
| 3 |
0x0008 |
upper texture is unpegged |
|
| 4 |
0x0010 |
lower texture is unpegged |
|
| 5 |
0x0020 |
secret (shows as one-sided on
automap) |
|
| 6 |
0x0040 |
blocks sound |
|
| 7 |
0x0080 |
never shows on automap |
|
| 8 |
0x0100 |
always shows on automap |
|
| 9 |
0x0200 |
can be activated more than once |
X |
| 10-12 |
0x0400 |
activated when used by player |
X |
| 10-12 |
0x0800 |
activated when crossed by monster |
X |
| 10-12 |
0x0C00 |
activated when hit by projectile |
X |
| 10-12 |
0x1000 |
activated when bumped player |
X |
| 10-12 |
0x1400 |
activated crossed by projectile |
X |
| 10-12 |
0x1800 |
activated when used by player (with
pass through) |
X |
| 13 |
0x2000 |
line can be activated by players and
monsters |
X |
| 14 |
0x4000 |
X |
|
| 15 |
0x8000 |
blocks everything (includes
gunshots & missiles) |
X |
