graph-layout/vendor/gioui.org/shader/gio/zcover.frag.2.glsl150

#version 150

uniform sampler2D tex;
uniform sampler2D cover;

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

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