shader: function()

in effects/seriously.tvglitch.js [102:171]

• 56 lines of code
• 1 McCabe index (conditional complexity)

			shader: function (inputs, shaderSource) {
				shaderSource.fragment = [
					'precision mediump float;',

					'#define HardLight(top, bottom)  (1.0 - 2.0 * (1.0 - top) * (1.0 - bottom))',

					'varying vec2 vTexCoord;',

					'uniform sampler2D source;',
					'uniform sampler2D particles;',
					'uniform float time;',
					'uniform float scanlines;',
					'uniform float lineSync;',
					'uniform float lineHeight;', //for scanlines and distortion
					'uniform float distortion;',
					'uniform float vsync;',
					'uniform float bars;',
					'uniform float frameSharpness;',
					'uniform float frameShape;',
					'uniform float frameLimit;',
					'uniform vec4 frameColor;',

					//todo: need much better pseudo-random number generator
					Seriously.util.shader.noiseHelpers +
					Seriously.util.shader.snoise2d +

					'void main(void) {',
					'	vec2 texCoord = vTexCoord;',

						//distortion
					'	float drandom = snoise(vec2(time * 50.0, texCoord.y /lineHeight));',
					'	float distortAmount = distortion * (drandom - 0.25) * 0.5;',
						//line sync
					'	vec4 particleOffset = texture2D(particles, vec2(0.0, texCoord.y));',
					'	distortAmount -= lineSync * (2.0 * particleOffset.a - 0.5);',

					'	texCoord.x -= distortAmount;',
					'	texCoord.x = mod(texCoord.x, 1.0);',

						//vertical sync
					'	float roll;',
					'	if (vsync != 0.0) {',
					'		roll = fract(time / vsync);',
					'		texCoord.y = mod(texCoord.y - roll, 1.0);',
					'	}',

					'	vec4 pixel = texture2D(source, texCoord);',

						//horizontal bars
					'	float barsAmount = particleOffset.r;',
					'	if (barsAmount > 0.0) {',
					'		pixel = vec4(pixel.r + bars * barsAmount,' +
								'pixel.g + bars * barsAmount,' +
								'pixel.b + bars * barsAmount,' +
								'pixel.a);',
					'	}',

					'	if (mod(texCoord.y / lineHeight, 2.0) < 1.0 ) {',
					'		pixel.rgb *= (1.0 - scanlines);',
					'	}',

					'	float f = (1.0 - gl_FragCoord.x * gl_FragCoord.x) * (1.0 - gl_FragCoord.y * gl_FragCoord.y);',
					'	float frame = clamp( frameSharpness * (pow(f, frameShape) - frameLimit), 0.0, 1.0);',

					'	gl_FragColor = mix(frameColor, pixel, frame);',
					'}'
				].join('\n');

				return shaderSource;
			},