Update to render passes - generate scene half sized texture

examples/src/examples/graphics/clustered-lighting.example.mjs

@@ -100,7 +100,6 @@ assetListLoader.load(() => {
     const cylinderMesh = pc.Mesh.fromGeometry(app.graphicsDevice, new pc.CylinderGeometry({ capSegments: 200 }));
     const cylinder = new pc.Entity();
     cylinder.addComponent('render', {
-        material: material,
         meshInstances: [new pc.MeshInstance(cylinderMesh, material)],
         castShadows: true
     });

src/extras/render-passes/render-pass-bloom.js

@@ -9,6 +9,10 @@ import { RenderPassDownsample } from './render-pass-downsample.js';
 import { RenderPassUpsample } from './render-pass-upsample.js';
 import { math } from '../../core/math/math.js';
 
+/**
+ * @import { GraphicsDevice } from '../../platform/graphics/graphics-device.js'
+ */
+
 // based on https://learnopengl.com/Guest-Articles/2022/Phys.-Based-Bloom
 /**
  * Render pass implementation of HDR bloom effect.
@@ -27,6 +31,12 @@ class RenderPassBloom extends RenderPass {
 
     renderTargets = [];
 
+    /**
+     * @param {GraphicsDevice} device - The graphics device.
+     * @param {Texture} sourceTexture - The source texture, usually at half the resolution of the
+     * render target getting blurred.
+     * @param {number} format - The texture format.
+     */
     constructor(device, sourceTexture, format) {
         super(device);
         this._sourceTexture = sourceTexture;
@@ -95,8 +105,7 @@ class RenderPassBloom extends RenderPass {
         let passSourceTexture = this._sourceTexture;
         for (let i = 0; i < numPasses; i++) {
 
-            const fast = i === 0;  // fast box downscale for the first pass
-            const pass = new RenderPassDownsample(device, passSourceTexture, fast);
+            const pass = new RenderPassDownsample(device, passSourceTexture);
             const rt = this.renderTargets[i];
             pass.init(rt, {
                 resizeSource: passSourceTexture,
@@ -130,24 +139,6 @@ class RenderPassBloom extends RenderPass {
         this.destroyRenderTargets(1);
     }
 
-    set sourceTexture(value) {
-        this._sourceTexture = value;
-
-        if (this.beforePasses.length > 0) {
-            const firstPass = this.beforePasses[0];
-
-            // change resize source
-            firstPass.options.resizeSource = value;
-
-            // change downsample source
-            firstPass.sourceTexture = value;
-        }
-    }
-
-    get sourceTexture() {
-        return this._sourceTexture;
-    }
-
     frameUpdate() {
         super.frameUpdate();
 

src/extras/render-passes/render-pass-camera-frame.js

@@ -13,6 +13,8 @@ import { RenderPassPrepass } from './render-pass-prepass.js';
 import { RenderPassSsao } from './render-pass-ssao.js';
 import { SSAOTYPE_COMBINE, SSAOTYPE_LIGHTING, SSAOTYPE_NONE } from './constants.js';
 import { Debug } from '../../core/debug.js';
+import { RenderPassDownsample } from './render-pass-downsample.js';
+import { Color } from '../../core/math/color.js';
 
 class CameraFrameOptions {
     formats;
@@ -71,6 +73,8 @@ class RenderPassCameraFrame extends RenderPass {
 
     taaPass;
 
+    scenePassHalf;
+
     _renderTargetScale = 1;
 
     /**
@@ -96,13 +100,20 @@ class RenderPassCameraFrame extends RenderPass {
     reset() {
 
         this.sceneTexture = null;
+        this.sceneTextureHalf = null;
 
         if (this.rt) {
             this.rt.destroyTextureBuffers();
             this.rt.destroy();
             this.rt = null;
         }
 
+        if (this.rtHalf) {
+            this.rtHalf.destroyTextureBuffers();
+            this.rtHalf.destroy();
+            this.rtHalf = null;
+        }
+
         // destroy all passes we created
         this.beforePasses.forEach(pass => pass.destroy());
         this.beforePasses.length = 0;
@@ -116,6 +127,7 @@ class RenderPassCameraFrame extends RenderPass {
         this.ssaoPass = null;
         this.taaPass = null;
         this.afterPass = null;
+        this.scenePassHalf = null;
     }
 
     sanitizeOptions(options) {
@@ -180,6 +192,29 @@ class RenderPassCameraFrame extends RenderPass {
         }
     }
 
+    createRenderTarget(name, depth, stencil, samples, flipY) {
+
+        const texture = new Texture(this.device, {
+            name: name,
+            width: 4,
+            height: 4,
+            format: this.hdrFormat,
+            mipmaps: false,
+            minFilter: FILTER_LINEAR,
+            magFilter: FILTER_LINEAR,
+            addressU: ADDRESS_CLAMP_TO_EDGE,
+            addressV: ADDRESS_CLAMP_TO_EDGE
+        });
+
+        return new RenderTarget({
+            colorBuffer: texture,
+            depth: depth,
+            stencil: stencil,
+            samples: samples,
+            flipY: flipY
+        });
+    }
+
     setupRenderPasses(options) {
 
         const { device } = this;
@@ -188,6 +223,12 @@ class RenderPassCameraFrame extends RenderPass {
 
         this.hdrFormat = device.getRenderableHdrFormat(options.formats, true, options.samples) || PIXELFORMAT_RGBA8;
 
+        // HDR bloom is not supported on RGBA8 format
+        this._bloomEnabled = options.bloomEnabled && this.hdrFormat !== PIXELFORMAT_RGBA8;
+
+        // bloom needs half resolution scene texture
+        this._sceneHalfEnabled = this._bloomEnabled;
+
         // camera renders in HDR mode (linear output, no tonemapping)
         cameraComponent.gammaCorrection = GAMMA_NONE;
         cameraComponent.toneMapping = TONEMAP_NONE;
@@ -196,25 +237,15 @@ class RenderPassCameraFrame extends RenderPass {
         cameraComponent.shaderParams.ssaoEnabled = options.ssaoType === SSAOTYPE_LIGHTING;
 
         // create a render target to render the scene into
-        this.sceneTexture = new Texture(device, {
-            name: 'SceneColor',
-            width: 4,
-            height: 4,
-            format: this.hdrFormat,
-            mipmaps: false,
-            minFilter: FILTER_LINEAR,
-            magFilter: FILTER_LINEAR,
-            addressU: ADDRESS_CLAMP_TO_EDGE,
-            addressV: ADDRESS_CLAMP_TO_EDGE
-        });
-
-        this.rt = new RenderTarget({
-            colorBuffer: this.sceneTexture,
-            depth: true,
-            stencil: options.stencil,
-            samples: options.samples,
-            flipY: !!targetRenderTarget?.flipY  // flipY is inherited from the target renderTarget
-        });
+        const flipY = !!targetRenderTarget?.flipY; // flipY is inherited from the target renderTarget
+        this.rt = this.createRenderTarget('SceneColor', true, options.stencil, options.samples, flipY);
+        this.sceneTexture = this.rt.colorBuffer;
+
+        // when half size scene color buffer is used
+        if (this._sceneHalfEnabled) {
+            this.rtHalf = this.createRenderTarget('SceneColorHalf', false, false, 1, flipY);
+            this.sceneTextureHalf = this.rtHalf.colorBuffer;
+        }
 
         this.sceneOptions = {
             resizeSource: targetRenderTarget,
@@ -231,7 +262,7 @@ class RenderPassCameraFrame extends RenderPass {
     collectPasses() {
 
         // use these prepared render passes in the order they should be executed
-        return [this.prePass, this.ssaoPass, this.scenePass, this.colorGrabPass, this.scenePassTransparent, this.taaPass, this.bloomPass, this.composePass, this.afterPass];
+        return [this.prePass, this.ssaoPass, this.scenePass, this.colorGrabPass, this.scenePassTransparent, this.taaPass, this.scenePassHalf, this.bloomPass, this.composePass, this.afterPass];
     }
 
     createPasses(options) {
@@ -248,8 +279,11 @@ class RenderPassCameraFrame extends RenderPass {
         // TAA
         const sceneTextureWithTaa = this.setupTaaPass(options);
 
+        // downscale to half resolution
+        this.setupSceneHalfPass(options, sceneTextureWithTaa);
+
         // bloom
-        this.setupBloomPass(options, sceneTextureWithTaa);
+        this.setupBloomPass(options, this.sceneTextureHalf);
 
         // compose
         this.setupComposePass(options);
@@ -328,9 +362,23 @@ class RenderPassCameraFrame extends RenderPass {
         }
     }
 
+    setupSceneHalfPass(options, sourceTexture) {
+
+        if (this._sceneHalfEnabled) {
+            this.scenePassHalf = new RenderPassDownsample(this.device, this.sceneTexture, true);
+            this.scenePassHalf.name = 'RenderPassSceneHalf';
+            this.scenePassHalf.init(this.rtHalf, {
+                resizeSource: sourceTexture,
+                scaleX: 0.5,
+                scaleY: 0.5
+            });
+            this.scenePassHalf.setClearColor(Color.BLACK);
+        }
+    }
+
     setupBloomPass(options, inputTexture) {
-        // HDR bloom is not supported on RGBA8 format
-        if (options.bloomEnabled && this.hdrFormat !== PIXELFORMAT_RGBA8) {
+
+        if (this._bloomEnabled) {
             // create a bloom pass, which generates bloom texture based on the provided texture
             this.bloomPass = new RenderPassBloom(this.device, inputTexture, this.hdrFormat);
         }
@@ -387,9 +435,7 @@ class RenderPassCameraFrame extends RenderPass {
 
         // TAA history buffer is double buffered, assign the current one to the follow up passes.
         this.composePass.sceneTexture = sceneTexture;
-        if (this.options.bloomEnabled && this.bloomPass) {
-            this.bloomPass.sourceTexture = sceneTexture;
-        }
+        this.scenePassHalf?.setSourceTexture(sceneTexture);
     }
 }
 

src/extras/render-passes/render-pass-downsample.js

@@ -61,6 +61,13 @@ class RenderPassDownsample extends RenderPassShaderQuad {
         this.sourceInvResolutionValue = new Float32Array(2);
     }
 
+    setSourceTexture(value) {
+        this._sourceTexture = value;
+
+        // change resize source
+        this.options.resizeSource = value;
+    }
+
     execute() {
         this.sourceTextureId.setValue(this.sourceTexture);
 

src/platform/graphics/render-target.js

@@ -312,13 +312,13 @@ class RenderTarget {
      */
     resize(width, height) {
 
-        if (this.mipLevel > 0) {
-            Debug.warn('Only render target rendering to mipLevel 0 can be resized, ignoring.', this);
-            return;
-        }
-
         if (this.width !== width || this.height !== height) {
 
+            if (this.mipLevel > 0) {
+                Debug.warn('Only a render target rendering to mipLevel 0 can be resized, ignoring.', this);
+                return;
+            }
+
             // release existing
             const device = this._device;
             this.destroyFrameBuffers();