SuperTuxKart 1.5 upstream source (from official release tarball)

data/shaders/ge_shaders/fullscreen_quad.vert

@@ -0,0 +1,7 @@
+layout (location = 0) out vec2 f_uv;
+
+void main()
+{
+    f_uv = vec2((gl_VertexIndex << 1) & 2, gl_VertexIndex & 2);
+    gl_Position = vec4(f_uv * 2.0 - 1.0, 1.0, 1.0);
+}