package com.marshalchen.common.uimodule.imageprocessing.filter.blend;
import com.marshalchen.common.uimodule.imageprocessing.filter.MultiInputFilter;
/**
* Applies an additive blend of two images
* @author Chris Batt
*/
public class AddBlendFilter extends MultiInputFilter {
public AddBlendFilter() {
super(2);
}
@Override
protected String getFragmentShader() {
return
"precision mediump float;\n"
+"uniform sampler2D "+UNIFORM_TEXTURE0+";\n"
+"uniform sampler2D "+UNIFORM_TEXTUREBASE+1+";\n"
+"varying vec2 "+VARYING_TEXCOORD+";\n"
+"void main(){\n"
+" vec4 color1 = texture2D("+UNIFORM_TEXTURE0+","+VARYING_TEXCOORD+");\n"
+" vec4 color2 = texture2D("+UNIFORM_TEXTUREBASE+1+","+VARYING_TEXCOORD+");\n"
+" float r;\n"
+" if (color2.r * color1.a + color1.r * color2.a >= color2.a * color1.a) {\n"
+" r = color2.a * color1.a + color2.r * (1.0 - color1.a) + color1.r * (1.0 - color2.a);\n"
+" } else {\n"
+" r = color2.r + color1.r;\n"
+" }\n"
+" float g;\n"
+" if (color2.g * color1.a + color1.g * color2.a >= color2.a * color1.a) {\n"
+" g = color2.a * color1.a + color2.g * (1.0 - color1.a) + color1.g * (1.0 - color2.a);\n"
+" } else {\n"
+" g = color2.g + color1.g;\n"
+" }\n"
+" float b;\n"
+" if (color2.b * color1.a + color1.b * color2.a >= color2.a * color1.a) {\n"
+" r = color2.a * color1.a + color2.b * (1.0 - color1.a) + color1.b * (1.0 - color2.a);\n"
+" } else {\n"
+" r = color2.b + color1.b;\n"
+" }\n"
+" float a = color2.a + color1.a - color2.a * color1.a;\n"
+" gl_FragColor = vec4(r, g, b, a);\n"
+"}\n";
}
}