#version 450

layout(location = 1) out vec2 o_texcoord;

void main()
{ 
    vec2 coord = vec2(
        float(gl_VertexIndex & 2),
        float(gl_VertexIndex & 1) * 2.0f);

    o_texcoord  = coord;
    gl_Position = vec4(-1.0f + 2.0f * coord, 0.0f, 1.0f);
}