vertex_shader [[
	out vec2 v_uv;
	void main() {
		v_uv = vec2(gl_VertexID & 1, (gl_VertexID & 2) * 0.5);
		vec4 pos = vec4((gl_VertexID & 1) * 2 - 1, (gl_VertexID & 2) - 1, 0, 1);
		gl_Position = pos;
	}
]]


fragment_shader [[
	layout (binding=0) uniform sampler2D u_source;

	in vec2 v_uv;
	out vec4 o_color;

	void main() {
		o_color.rgb = texture(u_source, v_uv).rgb;
		o_color.w = 1;
	}
]]