physarum/vendor/gioui.org/shader/gio/zcover.frag.0.glsl150

#version 150

struct Color
{
    vec4 color;
};

uniform Color _color;

uniform sampler2D cover;

out vec4 fragColor;
in vec2 vCoverUV;
in vec2 vUV;

void main()
{
    fragColor = _color.color;
    float c = min(abs(texture(cover, vCoverUV).x), 1.0);
    fragColor *= c;
}