#version 440

layout(location = 0) in vec2 qt_TexCoord0;
layout(location = 0) out vec4 fragColor;

layout(std140, binding = 0) uniform buf {
    // qt_Matrix and qt_Opacity must always be both present
    // if the built-in vertex shader is used.
    mat4 qt_Matrix;
    float qt_Opacity;
};

layout(binding = 1) uniform sampler2D source;
layout(binding = 2) uniform sampler2D maskSource;

void main()
{
    if (texture(maskSource, qt_TexCoord0.st).a == 0.0) {
        fragColor = vec4(0);
    } else {
        fragColor = texture(source, qt_TexCoord0.st);
    }

    //fragColor = texture(source, qt_TexCoord0.st)
    //            * (texture(maskSource, qt_TexCoord0.st).a)
    //            * qt_Opacity;
}