[require]
GLSL >= 1.20

[vertex shader]
varying vec4 values[4];
uniform int index;
void main()
{
	values[0] = vec4(0.2);
	values[index] = vec4(0.4);
	values[2] = vec4(0.6);
	values[3] = vec4(0.7);
	gl_Position = gl_Vertex;
}

[fragment shader]
varying vec4 values[4];
uniform float f0;
uniform float f1;
void main()
{
	gl_FragColor = (f0 * values[0] +
			f1 * values[1] +
			f0 * values[2] +
			f0 * values[3]);
}

[test]
uniform int index 1
uniform float f0 0.0
uniform float f1 1.0
draw rect -1 -1 2 2
probe rgba 1 1 0.4 0.4 0.4 0.4