playcanvas/build/playcanvas/src/scene/gsplat/gsplat-compressed-resource.js

PlayCanvas WebGL game engine

import { Vec2 } from '../../core/math/vec2.js';
import { PIXELFORMAT_RGBA32U, PIXELFORMAT_RGBA32F } from '../../platform/graphics/constants.js';
import { GSplatResourceBase } from './gsplat-resource-base.js';

const strideCopy = (target, targetStride, src, srcStride, numEntries)=>{
		for(let i = 0; i < numEntries; ++i){
				for(let j = 0; j < srcStride; ++j){
						target[i * targetStride + j] = src[i * srcStride + j];
				}
		}
};
class GSplatCompressedResource extends GSplatResourceBase {
		constructor(device, gsplatData){
				super(device, gsplatData);
				const { chunkData, chunkSize, numChunks, numSplats, vertexData, shBands } = gsplatData;
				this.chunks = new Float32Array(numChunks * 6);
				gsplatData.getChunks(this.chunks);
				this.packedTexture = this.createTexture('packedData', PIXELFORMAT_RGBA32U, this.evalTextureSize(numSplats), vertexData);
				const chunkTextureSize = this.evalTextureSize(numChunks);
				chunkTextureSize.x *= 5;
				this.chunkTexture = this.createTexture('chunkData', PIXELFORMAT_RGBA32F, chunkTextureSize);
				const chunkTextureData = this.chunkTexture.lock();
				strideCopy(chunkTextureData, 20, chunkData, chunkSize, numChunks);
				if (chunkSize === 12) {
						for(let i = 0; i < numChunks; ++i){
								chunkTextureData[i * 20 + 15] = 1;
								chunkTextureData[i * 20 + 16] = 1;
								chunkTextureData[i * 20 + 17] = 1;
						}
				}
				this.chunkTexture.unlock();
				if (shBands > 0) {
						const size = this.evalTextureSize(numSplats);
						this.shTexture0 = this.createTexture('shTexture0', PIXELFORMAT_RGBA32U, size, new Uint32Array(gsplatData.shData0.buffer));
						this.shTexture1 = this.createTexture('shTexture1', PIXELFORMAT_RGBA32U, size, new Uint32Array(gsplatData.shData1.buffer));
						this.shTexture2 = this.createTexture('shTexture2', PIXELFORMAT_RGBA32U, size, new Uint32Array(gsplatData.shData2.buffer));
				} else {
						this.shTexture0 = null;
						this.shTexture1 = null;
						this.shTexture2 = null;
				}
		}
		destroy() {
				this.packedTexture?.destroy();
				this.chunkTexture?.destroy();
				this.shTexture0?.destroy();
				this.shTexture1?.destroy();
				this.shTexture2?.destroy();
				super.destroy();
		}
		configureMaterial(material) {
				material.setDefine('GSPLAT_COMPRESSED_DATA', true);
				material.setParameter('packedTexture', this.packedTexture);
				material.setParameter('chunkTexture', this.chunkTexture);
				if (this.shTexture0) {
						material.setDefine('SH_BANDS', 3);
						material.setParameter('shTexture0', this.shTexture0);
						material.setParameter('shTexture1', this.shTexture1);
						material.setParameter('shTexture2', this.shTexture2);
				} else {
						material.setDefine('SH_BANDS', 0);
				}
		}
		evalTextureSize(count) {
				const width = Math.ceil(Math.sqrt(count));
				const height = Math.ceil(count / width);
				return new Vec2(width, height);
		}
}

export { GSplatCompressedResource };