layout (location = 0) in vec2 aPos; // pixels, origin bottom-left
layout (location = 1) in vec2 aUV;

uniform vec2 screenSize;

out vec2 UV;

void main() {
    vec2 ndc    = (aPos / screenSize) * 2.0 - 1.0;
    gl_Position = vec4(ndc, 0.0, 1.0);
    UV          = aUV;
}