playcanvas/build/playcanvas/src/scene/graphics/frame-pass-color-grab.js

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

import { ADDRESS_CLAMP_TO_EDGE, FILTER_LINEAR, FILTER_LINEAR_MIPMAP_LINEAR } from "../../platform/graphics/constants.js";
import { FramePass } from "../../platform/graphics/frame-pass.js";
import { RenderTarget } from "../../platform/graphics/render-target.js";
import { Texture } from "../../platform/graphics/texture.js";
const _colorUniformName = "uSceneColorMap";
class FramePassColorGrab extends FramePass {
	colorRenderTarget = null;
	source = null;
	destroy() {
		super.destroy();
		this.releaseRenderTarget(this.colorRenderTarget);
	}
	shouldReallocate(targetRT, sourceTexture, sourceFormat) {
		const targetFormat = targetRT?.colorBuffer.format;
		if (targetFormat !== sourceFormat) {
			return true;
		}
		const width = sourceTexture?.width || this.device.width;
		const height = sourceTexture?.height || this.device.height;
		return !targetRT || width !== targetRT.width || height !== targetRT.height;
	}
	allocateRenderTarget(renderTarget, sourceRenderTarget, device, format) {
		const texture = new Texture(device, {
			name: _colorUniformName,
			format,
			width: sourceRenderTarget ? sourceRenderTarget.colorBuffer.width : device.width,
			height: sourceRenderTarget ? sourceRenderTarget.colorBuffer.height : device.height,
			mipmaps: true,
			minFilter: FILTER_LINEAR_MIPMAP_LINEAR,
			magFilter: FILTER_LINEAR,
			addressU: ADDRESS_CLAMP_TO_EDGE,
			addressV: ADDRESS_CLAMP_TO_EDGE
		});
		if (renderTarget) {
			renderTarget.destroyFrameBuffers();
			renderTarget._colorBuffer = texture;
			renderTarget._colorBuffers = [texture];
			renderTarget.evaluateDimensions();
		} else {
			renderTarget = new RenderTarget({
				name: "ColorGrabRT",
				colorBuffer: texture,
				depth: false,
				stencil: false,
				autoResolve: false
			});
		}
		return renderTarget;
	}
	releaseRenderTarget(rt) {
		if (rt) {
			rt.destroyTextureBuffers();
			rt.destroy();
		}
	}
	frameUpdate() {
		const device = this.device;
		const sourceRt = this.source;
		const sourceFormat = sourceRt?.colorBuffer.format ?? this.device.backBufferFormat;
		if (this.shouldReallocate(this.colorRenderTarget, sourceRt?.colorBuffer, sourceFormat)) {
			this.releaseRenderTarget(this.colorRenderTarget);
			this.colorRenderTarget = this.allocateRenderTarget(this.colorRenderTarget, sourceRt, device, sourceFormat);
		}
		const colorBuffer = this.colorRenderTarget.colorBuffer;
		device.scope.resolve(_colorUniformName).setValue(colorBuffer);
	}
	execute() {
		const device = this.device;
		const sourceRt = this.source;
		const colorBuffer = this.colorRenderTarget.colorBuffer;
		if (device.isWebGPU) {
			device.copyRenderTarget(sourceRt, this.colorRenderTarget, true, false);
			device.mipmapRenderer.generate(this.colorRenderTarget.colorBuffer.impl);
		} else {
			device.copyRenderTarget(sourceRt, this.colorRenderTarget, true, false);
			device.activeTexture(device.maxCombinedTextures - 1);
			device.bindTexture(colorBuffer);
			device.gl.generateMipmap(colorBuffer.impl._glTarget);
		}
	}
}
export {
	FramePassColorGrab
};