[require] GL >= 2.0 GLSL >= 1.10 /* varying gl_TexCoord can be declared to different sizes between vertex and fragment shaders. See GLSL Spec v1.10, Section 7.6. */ [vertex shader] varying vec4 gl_TexCoord[2]; void main() { gl_Position = ftransform(); } [fragment shader] varying vec4 gl_TexCoord[1]; void main() { gl_FragColor = vec4(0.0, 1.0, 0.0 ,1.0); } [test] draw rect -1 -1 2 2 probe all rgba 0.0 1.0 0.0 1.0