[require] GLSL >= 1.10 [vertex shader] void main() { gl_Position = gl_Vertex; } [fragment shader] #version 110 void main() { float mat4x2 = 1.0; gl_FragColor = vec4(0.0, mat4x2, 0.0, 0.0); } [test] draw rect -1 -1 2 2 probe rgba 1 1 0.0 1.0 0.0 0.0