Skybox system

BSP worldspawn shaders are the normal source of sky information. The map pipeline resolves the six sky faces from PK3 assets and creates the Babylon skybox.

Console workflow

developer 1
bsp load wdm2
bsp render
bsp sky info
bsp sky apply
bsp sky toggle
bsp sky remove
bsp sky debug

bsp sky debug creates labeled colored faces for checking axis orientation.

The standalone skybox command inspects (skybox info) and clears (skybox clear) the current sky. Skies load with their map; skybox load <name> does not load an arbitrary sky.

API

import { SkyboxLoader } from '../../../src/engine/loader/texture/SkyboxLoader';

const skybox = SkyboxLoader.getInstance();
skybox.init(scene);

const result = await skybox.loadSkybox(basePath);
// or:
const textureResult = await skybox.loadSkyboxFromTexture(texturePath);

skybox.disposeSkybox();

Use the actual loader result to handle missing faces. Avoid creating a second skybox without disposing the previous map-owned one.

Cloud layers

A sky shader's texture stages are drawn as Quake 3 cloud layers, one dome per stage: over the far box when skyParms names one, and as the whole sky when it does not (skyParms - 2048 -).

• Texture coordinates follow Quake 3's cloud dome: each sky direction meets a sphere cloudHeight above a world of radius 4096, giving two angles in radians that tcMod scale then tiles.
• tcMod scale and tcMod scroll tile and move each layer; rgbGen const tints it; blendFunc picks how it combines (none or GL_ONE GL_ZERO opaque, GL_ONE GL_ONE add, a filter multiplies, GL_SRC_ALPHA GL_ONE_MINUS_SRC_ALPHA blends by alpha; anything else adds).
• The extension a stage names is a hint, as in Quake: foo.tga is also found as foo.ktx, foo.jpg or foo.png.

The layers are meshes named skybox_cloud_<n>; disposeSkybox() removes them with the far box.

Sky height

A sky shader's height is the cloud dome's height and, for world fog, how far away the sky is: Warfork draws the sky as a box scaled to it, so a sky at 512 stays clear inside a 700-unit fog start while one at 1500 hazes. A shader without a height (- or 0) is at 2048, Warfork's default. skyparmssides reads Warfork's six sides, each an image or the name of an earlier side, then the height: skyparmssides env/36sky rt rt rt rt rt 1500 - is env/36sky on every side at height 1500.

With a sky portal in the map, the sky meshes draw only in the portal's view; see the BSP guide.

Coordinate convention

Babylon and Quake sky-face naming use different viewing conventions. Keep the mapping centralized in SkyboxLoader; use the debug skybox before changing face order or rotations.

Source of truth

• src/engine/loader/texture/SkyboxLoader.ts
• src/engine/loader/bsp/mesh/skyClouds.ts (shader stages to cloud layers)
• src/engine/console/commands/BspCommand.ts
• src/engine/console/commands/SkyboxCommand.ts