#version 450
layout(location = 0) out vec2 v_uv;
void main() {
vec2 pos;
if (gl_VertexIndex == 0) {
pos = vec2(-1.0, -1.0);
} else if (gl_VertexIndex == 1) {
pos = vec2(-1.0, 3.0);
} else {
pos = vec2(3.0, -1.0);
}
v_uv = pos * 0.5 + 0.5;
gl_Position = vec4(pos, 0.0, 1.0);
}