[require]
GLSL >= 1.20

[vertex shader file]
glsl-mvp.vert

[fragment shader]
#version 120
void main() {
   const float zero = acos(1.0);
   const float half_pi = acos(0.0);
   const float pi = acos(-1.0);
   gl_FragColor = vec4(zero, half_pi - 1.0, pi - 3.0, 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 0.0 0.5707963267949 0.14159265358979