ConvolutionShader top-level property

Map ConvolutionShader
getter/setter pair

Convolution shader ported from o3d sample to WebGL / GLSL http://o3d.googlecode.com/svn/trunk/samples/convolution.html

Implementation

Map ConvolutionShader = {
  "defines": {'KERNEL_SIZE_FLOAT': '25.0', 'KERNEL_SIZE_INT': '25'},
  "uniforms": {
    'tDiffuse': {"value": null},
    'uImageIncrement': {"value": new Vector2(0.001953125, 0.0)},
    'cKernel': {"value": []}
  },
  "vertexShader": [
    'uniform vec2 uImageIncrement;',
    'varying vec2 vUv;',
    'void main() {',
    '	vUv = uv - ( ( KERNEL_SIZE_FLOAT - 1.0 ) / 2.0 ) * uImageIncrement;',
    '	gl_Position = projectionMatrix * modelViewMatrix * vec4( position, 1.0 );',
    '}'
  ].join('\n'),
  "fragmentShader": [
    'uniform float cKernel[ KERNEL_SIZE_INT ];',
    'uniform sampler2D tDiffuse;',
    'uniform vec2 uImageIncrement;',
    'varying vec2 vUv;',
    'void main() {',
    '	vec2 imageCoord = vUv;',
    '	vec4 sum = vec4( 0.0, 0.0, 0.0, 0.0 );',
    '	for( int i = 0; i < KERNEL_SIZE_INT; i ++ ) {',
    '		sum += texture2D( tDiffuse, imageCoord ) * cKernel[ i ];',
    '		imageCoord += uImageIncrement;',
    '	}',
    '	gl_FragColor = sum;',
    '}'
  ].join('\n'),
};