// GL Shading Language version 1.0 Fragment Shader
//  Orion Sky Lawlor, olawlor@acm.org, 2005/2/10 (Public Domain)

// Vertex/fragment shader interface
varying vec4 world; // World position
varying vec4 worldN; // World normal
varying vec4 albedo; // Material diffuse color
varying vec4 viewdir; // Viewer direction (to camera)

uniform sampler3D myNoise;

void main(void)
{
	vec4 L=gl_LightSource[0].position;
	vec4 N=worldN;
	N=normalize(N);
	
	// Diffuse term: usual lambertian+ambient
	float diffuse=(0.2+0.6*clamp(dot(N,L),0.0,1.0));
	
	vec4 specular=vec4(pow(dot(L,reflect(-viewdir,N)),100.0));
	
	vec4 c=texture3D(myNoise,vec3(world));
	
	gl_FragColor=diffuse*c+specular;
}