Sectors
Sectors are a group of lines that define an area. Thus the majority of time sectors are enclosed geometric shapes, which can be connected to other shapes. It is not a strict requirement that sectors are closed, however when they are not closed it can result in graphical glitches. Sectors define the moveable area, lighting, room sizes, and floor/ceiling textures. Additional sector properties can be assigned via flags and specials as defined in the subsequent sections. On the original engine, the minimum number of sectors is 2, while the maximum number of sectors is 32,767 (although blockmap and sidedef limits tend to be reached first).
Sector Flags
Sector flags are settings and properties you can apply to sectors. These tend to affect textures, sounds, and the player. In contrast, sector specials determine lighting effects and instant death for crushers.
| Flag Bit | Editor Setting | Description |
|---|---|---|
| 0x01 | Echo sounds | Reverb effect applied to sounds while in sector |
| 0x02 | Heavy Echo Sounds | Heavy reverb effect applied to sounds while in sector |
| 0x04 | Liquid Effect | Water effect (floors only). Blends two floor textures together (next texture is selected). |
| 0x08 | Sync Specials | All flagged sectors sync with unflagged lowest-numbered sector of same special type |
| 0x10 | Toggle Fast Scrolling | Scrolling floors/ceilings will scroll at twice the speed |
| 0x20 | Secret | Count as secret when entering this sector |
| 0x40 | Damage x5 | Damage player x5 (additive with other damage flags) |
| 0x80 | Damage x10 | Damage player x10 (additive with other damage flags) |
| 0x100 | Damage x20 | Damage player x20 (additive with other damage flags) |
| 0x200 | Hide on Automap | Hide sector in automap (hidden in the textured map mode) |
| 0x400 | Set Ceiling Scroll | Enable ceiling scrolling |
| 0x800 | Set Floor Scroll | Enable floor scrolling |
| 0x1000 | Scroll Left | Scroll floor/ceiling west |
| 0x2000 | Scroll Right | Scroll floor/ceiling east |
| 0x4000 | Scroll Up | Scroll floor/ceiling north |
| 0x8000 | Scroll Down | Scroll floor/ceiling south |
Sector Specials
Sector specials determine lighting effects and instant death for crushers. In contrast, sector flags are settings and properties that tend to affect textures, sounds, and the player. All light effects are additive to each color channel (greyscale).
| Flag Bit | Editor Setting | Description |
|---|---|---|
| 0 | Normal | (default) No special effect |
| 1 | Light Blinks (randomly) | Light which blinks (dims) randomly |
| 2 | Light Strobe (0.5 sec) | Light which brightens every half-second |
| 3 | Light Strobe (1 sec) | Light which brightens every second |
| 8 | Light Glows (normal) | Light which fades in and out |
| 9 | Light Glows (slow) | Light which fades in and out slowly |
| 11 | Light Glows (randomly) | Light which fades in and out randomly |
| 17 | Light Flickers (randomly) | Random light brightness flicker |
| 202 | Bright Light Strobe (0.1 sec) | Very bright light flashes every tenth of a second |
| 204 | Light Strobe (0.3 sec) | Light which brightens every third of a second |
| 205 | Sequence Starter | Starts a sequence of glowing lights. |
| 206 | Light Strobe (3 sec) | Light which brightens every three seconds |
| 208 | Bright Light Strobe (0.2 sec) | Very bright light flashes every fifth of a second |
| 666 | Instant Kill | Instantly kills any thing which gets crushed |
| 999 | Blind To Monsters (BSP64 En.) | Monsters are blind to sector with BSP64 Enhanced |
Lighting
Sectors define the lighting of Doom 64 in two styles. Each sector has five color values which define the gradient lighting of the sector: ceiling, top half wall, thing, bottom half wall, and floor. Then via the sector special value, additive lighting is defined. The following page describes the sector lighting in more detail.