playcanvas/build/playcanvas.dbg/src/scene/graphics/render-pass-radix-sort-count.js

Open-source WebGL/WebGPU 3D engine for the web

import { SHADERLANGUAGE_GLSL, SHADERLANGUAGE_WGSL, SEMANTIC_POSITION } from '../../platform/graphics/constants.js';
import { RenderPassShaderQuad } from './render-pass-shader-quad.js';
import { ShaderUtils } from '../shader-lib/shader-utils.js';
import { ShaderChunks } from '../shader-lib/shader-chunks.js';
import glslRadixSortCountPS from '../shader-lib/glsl/chunks/radix-sort/radix-sort-count.js';
import glslRadixSortCountQuad from '../shader-lib/glsl/chunks/radix-sort/radix-sort-count-quad.js';
import wgslRadixSortCountPS from '../shader-lib/wgsl/chunks/radix-sort/radix-sort-count.js';
import wgslRadixSortCountQuad from '../shader-lib/wgsl/chunks/radix-sort/radix-sort-count-quad.js';

/**
 * @import { GraphicsDevice } from '../../platform/graphics/graphics-device.js'
 * @import { Texture } from '../../platform/graphics/texture.js'
 */ /**
 * Render pass that counts digit occurrences per group (Pass 0 of radix sort).
 * Outputs to R32F prefix sums texture.
 *
 * Has two variants:
 * - sourceLinear=true: First pass, reads from user's linear-layout texture
 * - sourceLinear=false: Subsequent passes, reads from internal Morton-layout texture
 *
 * @category Graphics
 * @ignore
 */ class RenderPassRadixSortCount extends RenderPassShaderQuad {
    /**
     * Sets the keys texture to read from.
     *
     * @param {Texture} keysTexture - The keys texture (R32U).
     */ setKeysTexture(keysTexture) {
        this._keysTexture = keysTexture;
    }
    /**
     * Sets dynamic parameters (called each frame).
     *
     * @param {number} elementCount - Number of elements to sort.
     * @param {number} imageElementsLog2 - Log2 of total texture elements.
     */ setDynamicParams(elementCount, imageElementsLog2) {
        this._dynamicParams.elementCount = elementCount;
        this._dynamicParams.imageElementsLog2 = imageElementsLog2;
    }
    execute() {
        this.keysTextureId.setValue(this._keysTexture);
        this.bitsPerStepId.setValue(this.bitsPerStep);
        this.groupSizeId.setValue(this.groupSize);
        this.elementCountId.setValue(this._dynamicParams.elementCount);
        this.imageElementsLog2Id.setValue(this._dynamicParams.imageElementsLog2);
        this.currentBitId.setValue(this.currentBit);
        super.execute();
    }
    /**
     * @param {GraphicsDevice} device - The graphics device.
     * @param {boolean} sourceLinear - Whether to read from linear-layout source texture.
     * @param {number} bitsPerStep - Bits per radix step (usually 4).
     * @param {number} groupSize - Log2 of group size (usually 4 for 16 elements).
     * @param {number} currentBit - Current bit offset for this pass.
     */ constructor(device, sourceLinear, bitsPerStep, groupSize, currentBit){
        super(device), /**
     * Whether this pass reads from linear-layout source texture (first pass).
     *
     * @type {boolean}
     */ this.sourceLinear = false, /**
     * Bits per radix step (usually 4).
     *
     * @type {number}
     */ this.bitsPerStep = 0, /**
     * Log2 of group size (usually 4 for 16 elements).
     *
     * @type {number}
     */ this.groupSize = 0, /**
     * Current bit offset for this pass.
     *
     * @type {number}
     */ this.currentBit = 0, /**
     * Dynamic params updated per frame.
     *
     * @type {{elementCount: number, imageElementsLog2: number}}
     * @private
     */ this._dynamicParams = {
            elementCount: 0,
            imageElementsLog2: 0
        };
        this.sourceLinear = sourceLinear;
        this.bitsPerStep = bitsPerStep;
        this.groupSize = groupSize;
        this.currentBit = currentBit;
        // Register shader chunks (main shader + quad include chunk)
        ShaderChunks.get(device, SHADERLANGUAGE_GLSL).set('radixSortCountPS', glslRadixSortCountPS);
        ShaderChunks.get(device, SHADERLANGUAGE_GLSL).set('radixSortCountQuad', glslRadixSortCountQuad);
        ShaderChunks.get(device, SHADERLANGUAGE_WGSL).set('radixSortCountPS', wgslRadixSortCountPS);
        ShaderChunks.get(device, SHADERLANGUAGE_WGSL).set('radixSortCountQuad', wgslRadixSortCountQuad);
        const defines = new Map();
        if (sourceLinear) {
            defines.set('SOURCE_LINEAR', '');
        }
        const shaderName = sourceLinear ? 'RadixSortCountShaderLinear' : 'RadixSortCountShader';
        this.shader = ShaderUtils.createShader(device, {
            uniqueName: shaderName,
            attributes: {
                aPosition: SEMANTIC_POSITION
            },
            vertexChunk: 'quadVS',
            fragmentChunk: 'radixSortCountPS',
            fragmentDefines: defines,
            fragmentOutputTypes: 'float'
        });
        // Resolve uniform locations
        this.keysTextureId = device.scope.resolve('keysTexture');
        this.bitsPerStepId = device.scope.resolve('bitsPerStep');
        this.groupSizeId = device.scope.resolve('groupSize');
        this.elementCountId = device.scope.resolve('elementCount');
        this.imageElementsLog2Id = device.scope.resolve('imageElementsLog2');
        this.currentBitId = device.scope.resolve('currentBit');
    }
}

export { RenderPassRadixSortCount };