package com.marshalchen.common.uimodule.imageprocessing.filter.blend;
import com.marshalchen.common.uimodule.imageprocessing.filter.MultiInputFilter;
/**
* Applies a normal blend of two images
* @author Chris Batt
*/
public class NormalBlendFilter extends MultiInputFilter {
public NormalBlendFilter() {
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 color2 = texture2D("+UNIFORM_TEXTURE0+","+VARYING_TEXCOORD+");\n"
+" vec4 color1 = texture2D("+UNIFORM_TEXTUREBASE+1+","+VARYING_TEXCOORD+");\n"
+" vec4 outputColor;\n"
+" float a = color1.a + color2.a * (1.0 - color1.a);\n"
+" outputColor.r = (color1.r * color1.a + color2.r * color2.a * (1.0 - color1.a))/a;\n"
+" outputColor.g = (color1.g * color1.a + color2.g * color2.a * (1.0 - color1.a))/a;\n"
+" outputColor.b = (color1.b * color1.a + color2.b * color2.a * (1.0 - color1.a))/a;\n"
+" outputColor.a = a;\n"
+" gl_FragColor = outputColor;\n"
+"}\n";
}
}