#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);
}