[require]
GLSL >= 1.20

[vertex shader]
void main()
{
	gl_Position = gl_ModelViewProjectionMatrix * gl_Vertex;
}

[fragment shader]
void main()
{
    const vec4 v1 = vec4(1.0, 0.0, 2.0, 0.0);
    const vec4 v2 = vec4(0.0, 1.0, 0.0, 2.0);
    const vec4 v3 = vec4(0.5, 0.5, 0.75, 0.25);
    const vec4 vm = mix(v1, v2, v3);
    gl_FragColor = vm;
}

[test]
draw rect -1 -1 2 2
probe all rgb 0.5 0.5 0.5