three
Version:
JavaScript 3D library
364 lines (266 loc) • 8.48 kB
JavaScript
import {
Clock,
HalfFloatType,
NoBlending,
Vector2,
WebGLRenderTarget
} from 'three';
import { CopyShader } from '../shaders/CopyShader.js';
import { ShaderPass } from './ShaderPass.js';
import { ClearMaskPass, MaskPass } from './MaskPass.js';
/**
* Used to implement post-processing effects in three.js.
* The class manages a chain of post-processing passes to produce the final visual result.
* Post-processing passes are executed in order of their addition/insertion.
* The last pass is automatically rendered to screen.
*
* This module can only be used with {@link WebGLRenderer}.
*
* ```js
* const composer = new EffectComposer( renderer );
*
* // adding some passes
* const renderPass = new RenderPass( scene, camera );
* composer.addPass( renderPass );
*
* const glitchPass = new GlitchPass();
* composer.addPass( glitchPass );
*
* const outputPass = new OutputPass()
* composer.addPass( outputPass );
*
* function animate() {
*
* composer.render(); // instead of renderer.render()
*
* }
* ```
*
* @three_import import { EffectComposer } from 'three/addons/postprocessing/EffectComposer.js';
*/
class EffectComposer {
/**
* Constructs a new effect composer.
*
* @param {WebGLRenderer} renderer - The renderer.
* @param {WebGLRenderTarget} [renderTarget] - This render target and a clone will
* be used as the internal read and write buffers. If not given, the composer creates
* the buffers automatically.
*/
constructor( renderer, renderTarget ) {
/**
* The renderer.
*
* @type {WebGLRenderer}
*/
this.renderer = renderer;
this._pixelRatio = renderer.getPixelRatio();
if ( renderTarget === undefined ) {
const size = renderer.getSize( new Vector2() );
this._width = size.width;
this._height = size.height;
renderTarget = new WebGLRenderTarget( this._width * this._pixelRatio, this._height * this._pixelRatio, { type: HalfFloatType } );
renderTarget.texture.name = 'EffectComposer.rt1';
} else {
this._width = renderTarget.width;
this._height = renderTarget.height;
}
this.renderTarget1 = renderTarget;
this.renderTarget2 = renderTarget.clone();
this.renderTarget2.texture.name = 'EffectComposer.rt2';
/**
* A reference to the internal write buffer. Passes usually write
* their result into this buffer.
*
* @type {WebGLRenderTarget}
*/
this.writeBuffer = this.renderTarget1;
/**
* A reference to the internal read buffer. Passes usually read
* the previous render result from this buffer.
*
* @type {WebGLRenderTarget}
*/
this.readBuffer = this.renderTarget2;
/**
* Whether the final pass is rendered to the screen (default framebuffer) or not.
*
* @type {boolean}
* @default true
*/
this.renderToScreen = true;
/**
* An array representing the (ordered) chain of post-processing passes.
*
* @type {Array<Pass>}
*/
this.passes = [];
/**
* A copy pass used for internal swap operations.
*
* @private
* @type {ShaderPass}
*/
this.copyPass = new ShaderPass( CopyShader );
this.copyPass.material.blending = NoBlending;
/**
* The internal clock for managing time data.
*
* @private
* @type {Clock}
*/
this.clock = new Clock();
}
/**
* Swaps the internal read/write buffers.
*/
swapBuffers() {
const tmp = this.readBuffer;
this.readBuffer = this.writeBuffer;
this.writeBuffer = tmp;
}
/**
* Adds the given pass to the pass chain.
*
* @param {Pass} pass - The pass to add.
*/
addPass( pass ) {
this.passes.push( pass );
pass.setSize( this._width * this._pixelRatio, this._height * this._pixelRatio );
}
/**
* Inserts the given pass at a given index.
*
* @param {Pass} pass - The pass to insert.
* @param {number} index - The index into the pass chain.
*/
insertPass( pass, index ) {
this.passes.splice( index, 0, pass );
pass.setSize( this._width * this._pixelRatio, this._height * this._pixelRatio );
}
/**
* Removes the given pass from the pass chain.
*
* @param {Pass} pass - The pass to remove.
*/
removePass( pass ) {
const index = this.passes.indexOf( pass );
if ( index !== - 1 ) {
this.passes.splice( index, 1 );
}
}
/**
* Returns `true` if the pass for the given index is the last enabled pass in the pass chain.
*
* @param {number} passIndex - The pass index.
* @return {boolean} Whether the pass for the given index is the last pass in the pass chain.
*/
isLastEnabledPass( passIndex ) {
for ( let i = passIndex + 1; i < this.passes.length; i ++ ) {
if ( this.passes[ i ].enabled ) {
return false;
}
}
return true;
}
/**
* Executes all enabled post-processing passes in order to produce the final frame.
*
* @param {number} deltaTime - The delta time in seconds. If not given, the composer computes
* its own time delta value.
*/
render( deltaTime ) {
// deltaTime value is in seconds
if ( deltaTime === undefined ) {
deltaTime = this.clock.getDelta();
}
const currentRenderTarget = this.renderer.getRenderTarget();
let maskActive = false;
for ( let i = 0, il = this.passes.length; i < il; i ++ ) {
const pass = this.passes[ i ];
if ( pass.enabled === false ) continue;
pass.renderToScreen = ( this.renderToScreen && this.isLastEnabledPass( i ) );
pass.render( this.renderer, this.writeBuffer, this.readBuffer, deltaTime, maskActive );
if ( pass.needsSwap ) {
if ( maskActive ) {
const context = this.renderer.getContext();
const stencil = this.renderer.state.buffers.stencil;
//context.stencilFunc( context.NOTEQUAL, 1, 0xffffffff );
stencil.setFunc( context.NOTEQUAL, 1, 0xffffffff );
this.copyPass.render( this.renderer, this.writeBuffer, this.readBuffer, deltaTime );
//context.stencilFunc( context.EQUAL, 1, 0xffffffff );
stencil.setFunc( context.EQUAL, 1, 0xffffffff );
}
this.swapBuffers();
}
if ( MaskPass !== undefined ) {
if ( pass instanceof MaskPass ) {
maskActive = true;
} else if ( pass instanceof ClearMaskPass ) {
maskActive = false;
}
}
}
this.renderer.setRenderTarget( currentRenderTarget );
}
/**
* Resets the internal state of the EffectComposer.
*
* @param {WebGLRenderTarget} [renderTarget] - This render target has the same purpose like
* the one from the constructor. If set, it is used to setup the read and write buffers.
*/
reset( renderTarget ) {
if ( renderTarget === undefined ) {
const size = this.renderer.getSize( new Vector2() );
this._pixelRatio = this.renderer.getPixelRatio();
this._width = size.width;
this._height = size.height;
renderTarget = this.renderTarget1.clone();
renderTarget.setSize( this._width * this._pixelRatio, this._height * this._pixelRatio );
}
this.renderTarget1.dispose();
this.renderTarget2.dispose();
this.renderTarget1 = renderTarget;
this.renderTarget2 = renderTarget.clone();
this.writeBuffer = this.renderTarget1;
this.readBuffer = this.renderTarget2;
}
/**
* Resizes the internal read and write buffers as well as all passes. Similar to {@link WebGLRenderer#setSize},
* this method honors the current pixel ration.
*
* @param {number} width - The width in logical pixels.
* @param {number} height - The height in logical pixels.
*/
setSize( width, height ) {
this._width = width;
this._height = height;
const effectiveWidth = this._width * this._pixelRatio;
const effectiveHeight = this._height * this._pixelRatio;
this.renderTarget1.setSize( effectiveWidth, effectiveHeight );
this.renderTarget2.setSize( effectiveWidth, effectiveHeight );
for ( let i = 0; i < this.passes.length; i ++ ) {
this.passes[ i ].setSize( effectiveWidth, effectiveHeight );
}
}
/**
* Sets device pixel ratio. This is usually used for HiDPI device to prevent blurring output.
* Setting the pixel ratio will automatically resize the composer.
*
* @param {number} pixelRatio - The pixel ratio to set.
*/
setPixelRatio( pixelRatio ) {
this._pixelRatio = pixelRatio;
this.setSize( this._width, this._height );
}
/**
* Frees the GPU-related resources allocated by this instance. Call this
* method whenever the composer is no longer used in your app.
*/
dispose() {
this.renderTarget1.dispose();
this.renderTarget2.dispose();
this.copyPass.dispose();
}
}
export { EffectComposer };