three.proton
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three.Proton is an easily customizable html5 particle engine for three.js
168 lines (122 loc) • 5 kB
JavaScript
/**
*
* Manual Multi-Sample Anti-Aliasing Render Pass
*
* @author bhouston / http://clara.io/
*
* This manual approach to MSAA re-renders the scene ones for each sample with camera jitter and accumulates the results.
*
* References: https://en.wikipedia.org/wiki/Multisample_anti-aliasing
*
*/
THREE.ManualMSAARenderPass = function ( scene, camera, params ) {
THREE.Pass.call( this );
this.scene = scene;
this.camera = camera;
this.sampleLevel = 4; // specified as n, where the number of samples is 2^n, so sampleLevel = 4, is 2^4 samples, 16.
this.params = params || { minFilter: THREE.NearestFilter, magFilter: THREE.NearestFilter, format: THREE.RGBAFormat };
this.params.minFilter = THREE.NearestFilter;
this.params.maxFilter = THREE.NearestFilter;
if ( THREE.CompositeShader === undefined ) {
console.error( "THREE.ManualMSAARenderPass relies on THREE.CompositeShader" );
}
var compositeShader = THREE.CompositeShader;
this.compositeUniforms = THREE.UniformsUtils.clone( compositeShader.uniforms );
this.materialComposite = new THREE.ShaderMaterial( {
uniforms: this.compositeUniforms,
vertexShader: compositeShader.vertexShader,
fragmentShader: compositeShader.fragmentShader,
transparent: true,
blending: THREE.CustomBlending,
blendSrc: THREE.OneFactor,
blendDst: THREE.OneFactor,
blendSrcAlpha: THREE.OneFactor,
blendDstAlpha: THREE.OneFactor,
blendEquation: THREE.AddEquation,
depthTest: false,
depthWrite: false
} );
this.camera2 = new THREE.OrthographicCamera( - 1, 1, 1, - 1, 0, 1 );
this.scene2 = new THREE.Scene();
this.quad2 = new THREE.Mesh( new THREE.PlaneGeometry( 2, 2 ), this.materialComposite );
this.scene2.add( this.quad2 );
};
THREE.ManualMSAARenderPass.prototype = Object.create( THREE.Pass.prototype );
THREE.ManualMSAARenderPass.prototype = {
constructor: THREE.ManualMSAARenderPass,
dispose: function() {
if ( this.sampleRenderTarget ) {
this.sampleRenderTarget.dispose();
this.sampleRenderTarget = null;
}
},
setSize: function ( width, height ) {
this.sampleRenderTarget.setSize( width, height );
},
render: function ( renderer, writeBuffer, readBuffer, delta, maskActive ) {
var camera = ( this.camera || this.scene.camera );
var jitterOffsets = THREE.ManualMSAARenderPass.JitterVectors[ Math.max( 0, Math.min( this.sampleLevel, 5 ) ) ];
if( jitterOffsets.length === 1 ) {
renderer.render( this.scene, camera, writeBuffer, true );
return;
}
if ( ! this.sampleRenderTarget ) {
this.sampleRenderTarget = new THREE.WebGLRenderTarget( readBuffer.width, readBuffer.height, this.params );
}
var autoClear = renderer.autoClear;
renderer.autoClear = false;
this.compositeUniforms[ "scale" ].value = 1.0 / ( jitterOffsets.length );
this.compositeUniforms[ "tForeground" ].value = this.sampleRenderTarget;
// render the scene multiple times, each slightly jitter offset from the last and accumulate the results.
for ( var i = 0; i < jitterOffsets.length; i ++ ) {
// only jitters perspective cameras. TODO: add support for jittering orthogonal cameras
var jitterOffset = jitterOffsets[i];
if ( camera.setViewOffset ) {
camera.setViewOffset( readBuffer.width, readBuffer.height,
jitterOffset[ 0 ] * 0.0625, jitterOffset[ 1 ] * 0.0625, // 0.0625 = 1 / 16
readBuffer.width, readBuffer.height );
}
renderer.render( this.scene, this.camera, this.sampleRenderTarget, true );
renderer.render( this.scene2, this.camera2, writeBuffer, ( i === 0 ) );
}
// reset jitter to nothing. TODO: add support for orthogonal cameras
if ( camera.setViewOffset ) camera.setViewOffset( undefined, undefined, undefined, undefined, undefined, undefined );
renderer.autoClear = true;
}
};
// These jitter vectors are specified in integers because it is easier.
// I am assuming a [-8,8) integer grid, but it needs to be mapped onto [-0.5,0.5)
// before being used, thus these integers need to be scaled by 1/16.
//
// Sample patterns reference: https://msdn.microsoft.com/en-us/library/windows/desktop/ff476218%28v=vs.85%29.aspx?f=255&MSPPError=-2147217396
THREE.ManualMSAARenderPass.JitterVectors = [
[
[ 0, 0 ]
],
[
[ 4, 4 ], [ - 4, - 4 ]
],
[
[ - 2, - 6 ], [ 6, - 2 ], [ - 6, 2 ], [ 2, 6 ]
],
[
[ 1, - 3 ], [ - 1, 3 ], [ 5, 1 ], [ - 3, - 5 ],
[ - 5, 5 ], [ - 7, - 1 ], [ 3, 7 ], [ 7, - 7 ]
],
[
[ 1, 1 ], [ - 1, - 3 ], [ - 3, 2 ], [ 4, - 1 ],
[ - 5, - 2 ], [ 2, 5 ], [ 5, 3 ], [ 3, - 5 ],
[ - 2, 6 ], [ 0, - 7 ], [ - 4, - 6 ], [ - 6, 4 ],
[ - 8, 0 ], [ 7, - 4 ], [ 6, 7 ], [ - 7, - 8 ]
],
[
[ - 4, - 7 ], [ - 7, - 5 ], [ - 3, - 5 ], [ - 5, - 4 ],
[ - 1, - 4 ], [ - 2, - 2 ], [ - 6, - 1 ], [ - 4, 0 ],
[ - 7, 1 ], [ - 1, 2 ], [ - 6, 3 ], [ - 3, 3 ],
[ - 7, 6 ], [ - 3, 6 ], [ - 5, 7 ], [ - 1, 7 ],
[ 5, - 7 ], [ 1, - 6 ], [ 6, - 5 ], [ 4, - 4 ],
[ 2, - 3 ], [ 7, - 2 ], [ 1, - 1 ], [ 4, - 1 ],
[ 2, 1 ], [ 6, 2 ], [ 0, 4 ], [ 4, 4 ],
[ 2, 5 ], [ 7, 5 ], [ 5, 6 ], [ 3, 7 ]
]
];