playcanvas
Version:
PlayCanvas WebGL game engine
254 lines (251 loc) • 10.6 kB
JavaScript
import { Vec4 } from '../../core/math/vec4.js';
import { Texture } from '../../platform/graphics/texture.js';
import { reprojectTexture } from './reproject-texture.js';
import { ADDRESS_CLAMP_TO_EDGE, TEXTURETYPE_RGBP, TEXTURETYPE_DEFAULT, PIXELFORMAT_RGBA8, TEXTUREPROJECTION_EQUIRECT, PIXELFORMAT_RGBA16F, PIXELFORMAT_RGBA32F } from '../../platform/graphics/constants.js';
import { DebugGraphics } from '../../platform/graphics/debug-graphics.js';
// calculate the number of mipmap levels given texture dimensions
const calcLevels = (width, height = 0)=>{
return 1 + Math.floor(Math.log2(Math.max(width, height)));
};
const supportsFloat16 = (device)=>{
return device.textureHalfFloatRenderable;
};
const supportsFloat32 = (device)=>{
return device.textureFloatRenderable;
};
// lighting source should be stored HDR
const lightingSourcePixelFormat = (device)=>{
return supportsFloat16(device) ? PIXELFORMAT_RGBA16F : supportsFloat32(device) ? PIXELFORMAT_RGBA32F : PIXELFORMAT_RGBA8;
};
// runtime lighting can be RGBM
const lightingPixelFormat = (device)=>{
return PIXELFORMAT_RGBA8;
};
const createCubemap = (device, size, format, mipmaps)=>{
return new Texture(device, {
name: `lighting-${size}`,
cubemap: true,
width: size,
height: size,
format: format,
type: TEXTURETYPE_RGBP ,
addressU: ADDRESS_CLAMP_TO_EDGE,
addressV: ADDRESS_CLAMP_TO_EDGE,
mipmaps: false
});
};
/**
* Helper functions to support prefiltering lighting data.
*
* @ignore
*/ class EnvLighting {
/**
* Generate a skybox cubemap in the correct pixel format from the source texture.
*
* @param {Texture} source - The source texture. This is either a 2d texture in equirect format
* or a cubemap.
* @param {number} [size] - Size of the resulting texture. Otherwise use automatic sizing.
* @returns {Texture} The resulting cubemap.
*/ static generateSkyboxCubemap(source, size) {
const device = source.device;
DebugGraphics.pushGpuMarker(device, 'genSkyboxCubemap');
const result = createCubemap(device, size || (source.cubemap ? source.width : source.width / 4), PIXELFORMAT_RGBA8);
reprojectTexture(source, result, {
numSamples: 1024
});
DebugGraphics.popGpuMarker(device);
return result;
}
/**
* Create a texture in the format needed to precalculate lighting data.
*
* @param {Texture} source - The source texture. This is either a 2d texture in equirect format
* or a cubemap.
* @param {object} [options] - Specify generation options.
* @param {Texture} [options.target] - The target texture. If one is not provided then a
* new texture will be created and returned.
* @param {number} [options.size] - Size of the lighting source cubemap texture. Only used
* if target isn't specified. Defaults to 128.
* @returns {Texture} The resulting cubemap.
*/ static generateLightingSource(source, options) {
const device = source.device;
DebugGraphics.pushGpuMarker(device, 'genLightingSource');
const format = lightingSourcePixelFormat(device);
const result = options?.target || new Texture(device, {
name: 'lighting-source',
cubemap: true,
width: options?.size || 128,
height: options?.size || 128,
format: format,
type: format === PIXELFORMAT_RGBA8 ? TEXTURETYPE_RGBP : TEXTURETYPE_DEFAULT,
addressU: ADDRESS_CLAMP_TO_EDGE,
addressV: ADDRESS_CLAMP_TO_EDGE,
mipmaps: true
});
// copy into top level
reprojectTexture(source, result, {
numSamples: source.mipmaps ? 1 : 1024
});
DebugGraphics.popGpuMarker(device);
// generate mipmaps
return result;
}
/**
* Generate the environment lighting atlas containing prefiltered reflections and ambient.
*
* @param {Texture} source - The source lighting texture, generated by generateLightingSource.
* @param {object} [options] - Specify prefilter options.
* @param {Texture} [options.target] - The target texture. If one is not provided then a
* new texture will be created and returned.
* @param {number} [options.size] - Size of the target texture to create. Only used if
* target isn't specified. Defaults to 512.
* @param {number} [options.numReflectionSamples] - Number of samples to use when generating
* rough reflections. Defaults to 1024.
* @param {number} [options.numAmbientSamples] - Number of samples to use when generating ambient
* lighting. Defaults to 2048.
* @returns {Texture} The resulting atlas
*/ static generateAtlas(source, options) {
const device = source.device;
const format = lightingPixelFormat();
DebugGraphics.pushGpuMarker(device, 'genAtlas');
const result = options?.target || new Texture(device, {
name: 'envAtlas',
width: options?.size || 512,
height: options?.size || 512,
format: format,
type: TEXTURETYPE_RGBP ,
projection: TEXTUREPROJECTION_EQUIRECT,
addressU: ADDRESS_CLAMP_TO_EDGE,
addressV: ADDRESS_CLAMP_TO_EDGE,
mipmaps: false
});
DebugGraphics.pushGpuMarker(device, 'mipmaps');
const s = result.width / 512;
// generate mipmaps
const rect = new Vec4(0, 0, 512 * s, 256 * s);
const levels = calcLevels(256) - calcLevels(4);
for(let i = 0; i < levels; ++i){
reprojectTexture(source, result, {
numSamples: 1,
rect: rect,
seamPixels: s
});
rect.x += rect.w;
rect.y += rect.w;
rect.z = Math.max(1, Math.floor(rect.z * 0.5));
rect.w = Math.max(1, Math.floor(rect.w * 0.5));
}
DebugGraphics.popGpuMarker(device);
DebugGraphics.pushGpuMarker(device, 'reflections');
// generate blurry reflections
rect.set(0, 256 * s, 256 * s, 128 * s);
for(let i = 1; i < 7; ++i){
reprojectTexture(source, result, {
numSamples: options?.numReflectionSamples || 1024,
distribution: options?.distribution || 'ggx',
specularPower: Math.max(1, 2048 >> i * 2),
rect: rect,
seamPixels: s
});
rect.y += rect.w;
rect.z = Math.max(1, Math.floor(rect.z * 0.5));
rect.w = Math.max(1, Math.floor(rect.w * 0.5));
}
DebugGraphics.popGpuMarker(device);
DebugGraphics.pushGpuMarker(device, 'ambient');
// generate ambient
rect.set(128 * s, (256 + 128) * s, 64 * s, 32 * s);
reprojectTexture(source, result, {
numSamples: options?.numAmbientSamples || 2048,
distribution: 'lambert',
rect: rect,
seamPixels: s
});
DebugGraphics.popGpuMarker(device);
DebugGraphics.popGpuMarker(device);
return result;
}
/**
* Generate the environment lighting atlas from prefiltered cubemap data.
*
* @param {Texture[]} sources - Array of 6 prefiltered textures.
* @param {object} [options] - The options object
* @param {Texture} [options.target] - The target texture. If one is not provided then a
* new texture will be created and returned.
* @param {number} [options.size] - Size of the target texture to create. Only used if
* target isn't specified. Defaults to 512.
* @param {boolean} [options.legacyAmbient] - Enable generating legacy ambient lighting.
* Default is false.
* @param {number} [options.numSamples] - Number of samples to use when generating ambient
* lighting. Default is 2048.
* @returns {Texture} The resulting atlas texture.
*/ static generatePrefilteredAtlas(sources, options) {
const device = sources[0].device;
const format = sources[0].format;
const type = sources[0].type;
DebugGraphics.pushGpuMarker(device, 'genPrefilteredAtlas');
const result = options?.target || new Texture(device, {
name: 'envPrefilteredAtlas',
width: options?.size || 512,
height: options?.size || 512,
format: format,
type: type,
projection: TEXTUREPROJECTION_EQUIRECT,
addressU: ADDRESS_CLAMP_TO_EDGE,
addressV: ADDRESS_CLAMP_TO_EDGE,
mipmaps: false
});
DebugGraphics.pushGpuMarker(device, 'mipmaps');
const s = result.width / 512;
// generate mipmaps
const rect = new Vec4(0, 0, 512 * s, 256 * s);
const levels = calcLevels(512);
for(let i = 0; i < levels; ++i){
reprojectTexture(sources[0], result, {
numSamples: 1,
rect: rect,
seamPixels: s
});
rect.x += rect.w;
rect.y += rect.w;
rect.z = Math.max(1, Math.floor(rect.z * 0.5));
rect.w = Math.max(1, Math.floor(rect.w * 0.5));
}
DebugGraphics.popGpuMarker(device);
DebugGraphics.pushGpuMarker(device, 'reflections');
// copy blurry reflections
rect.set(0, 256 * s, 256 * s, 128 * s);
for(let i = 1; i < sources.length; ++i){
reprojectTexture(sources[i], result, {
numSamples: 1,
rect: rect,
seamPixels: s
});
rect.y += rect.w;
rect.z = Math.max(1, Math.floor(rect.z * 0.5));
rect.w = Math.max(1, Math.floor(rect.w * 0.5));
}
DebugGraphics.popGpuMarker(device);
DebugGraphics.pushGpuMarker(device, 'ambient');
// generate ambient
rect.set(128 * s, (256 + 128) * s, 64 * s, 32 * s);
if (options?.legacyAmbient) {
reprojectTexture(sources[5], result, {
numSamples: 1,
rect: rect,
seamPixels: s
});
} else {
reprojectTexture(sources[0], result, {
numSamples: options?.numSamples || 2048,
distribution: 'lambert',
rect: rect,
seamPixels: s
});
}
DebugGraphics.popGpuMarker(device);
DebugGraphics.popGpuMarker(device);
return result;
}
}
export { EnvLighting };