#version 450

layout (set = 0, binding = 0) uniform Descriptor {
	vec4 background_color;
	vec4 border_color;

    uint width;
    uint height;
    uint border_thickness;
} descriptor;

layout (location = 0) out vec4 out_color;

void main()
{
    vec2 st = gl_FragCoord.xy/vec2((float)descriptor.width, (float)descriptor.height);

    if ((uint)st.x <= descriptor.border_thickness ||
        (uint)st.x >= (descriptor.width - descriptor.border_thickness))
    {
        out_color = descriptor.border_color;
    }
    else if (
        (uint)st.y <= descriptor.border_thickness ||
        (uint)st.y >= (descriptor.height - descriptor.border_thickness)
    ) {
        out_color = descriptor.border_color;
    } else {
        out_color = descriptor.background_color;
    }
}