#version 410 core
// Attribute-less fullscreen triangle: 3 verts cover the whole screen.
out vec2 vUV;
void main() {
    vec2 verts[3] = vec2[](vec2(-1.0, -1.0), vec2(3.0, -1.0), vec2(-1.0, 3.0));
    vec2 p = verts[gl_VertexID];
    vUV = p * 0.5 + 0.5;
    gl_Position = vec4(p, 0.0, 1.0);
}
