playcanvas/build/playcanvas.dbg/src/extras/render-passes/render-pass-coc.js

PlayCanvas WebGL game engine

import { PROJECTION_ORTHOGRAPHIC } from '../../scene/constants.js';
import { RenderPassShaderQuad } from '../../scene/graphics/render-pass-shader-quad.js';
import { ChunkUtils } from '../../scene/shader-lib/chunk-utils.js';

/**
 * Render pass implementation of a Circle of Confusion texture generation, used by Depth of Field.
 * This pass generates a CoC texture based on the scene's depth buffer, and focus range and distance
 * parameters. The CoC texture stores far and near CoC values in the red and green channels.
 *
 * @category Graphics
 * @ignore
 */ class RenderPassCoC extends RenderPassShaderQuad {
    execute() {
        var { paramsValue, focusRange } = this;
        paramsValue[0] = this.focusDistance + 0.001;
        paramsValue[1] = focusRange;
        paramsValue[2] = 1 / focusRange;
        this.paramsId.setValue(paramsValue);
        var camera = this.cameraComponent.camera;
        var f = camera._farClip;
        this.cameraParams[0] = 1 / f;
        this.cameraParams[1] = f;
        this.cameraParams[2] = camera._nearClip;
        this.cameraParams[3] = camera.projection === PROJECTION_ORTHOGRAPHIC ? 1 : 0;
        this.cameraParamsId.setValue(this.cameraParams);
        super.execute();
    }
    constructor(device, cameraComponent, nearBlur){
        super(device);
        this.cameraComponent = cameraComponent;
        var screenDepth = ChunkUtils.getScreenDepthChunk(device, cameraComponent.shaderParams);
        this.shader = this.createQuadShader("CocShader-" + nearBlur, /* glsl */ "\n\n            " + (nearBlur ? '#define NEAR_BLUR' : '') + "\n            " + screenDepth + "\n            varying vec2 uv0;\n            uniform vec3 params;\n\n            void main()\n            {\n                float depth = getLinearScreenDepth(uv0);\n\n                // near and far focus ranges\n                float focusDistance = params.x;\n                float focusRange = params.y;\n                float invRange = params.z;\n                float farRange = focusDistance + focusRange * 0.5;\n                \n                // near and far CoC\n                float cocFar = min((depth - farRange) * invRange, 1.0);\n\n                #ifdef NEAR_BLUR\n                    float nearRange = focusDistance - focusRange * 0.5;\n                    float cocNear = min((nearRange - depth) * invRange, 1.0);\n                #else\n                    float cocNear = 0.0;\n                #endif\n\n                gl_FragColor = vec4(cocFar, cocNear, 0.0, 0.0);\n            }");
        this.paramsId = device.scope.resolve('params');
        this.paramsValue = new Float32Array(3);
        this.cameraParams = new Float32Array(4);
        this.cameraParamsId = device.scope.resolve('camera_params');
    }
}

export { RenderPassCoC };