[require] GLSL >= 1.20 [vertex shader file] glsl-mvp.vert [fragment shader] #version 120 void main() { const vec2 v1 = mod(vec2(-3.0, 43.5), vec2(0.9, -4.0)); /* (-0.5, 0.6) */ const vec2 v2 = mod(vec2(0.2, 6.0), 1.3); gl_FragColor = vec4(v1.x + v1.y, v2, 1.0); } [test] clear color 0.0 0.0 0.0 0.0 clear ortho draw rect 10 10 10 10 probe rgb 15 15 0.1 0.2 0.8