[require]
GLSL >= 1.10

[vertex shader]
varying float f;
void myfunc()
{
	f = 0.5;
}

[vertex shader]
varying float f;
void myfunc();
void main()
{
	f = 0.1;
	myfunc();
	gl_FrontColor.r = f++;
	gl_Position = gl_Vertex;
}

[fragment shader]
varying float f;
void main()
{	
	gl_FragColor = vec4(gl_Color.r, 0.0, 0.0, 1.0);
	
}

[test]
draw rect -1 -1 2 2
probe all rgba 0.5 0 0 1.0