//
// Fragment shader for producing clouds (mostly cloudy)
//
// Authors: John Kessenich, Randi Rost
//
// Copyright (c) 2002-2004 3Dlabs Inc. Ltd. 
//
// See 3Dlabs-License.txt for license information
//

varying float LightIntensity;
varying vec3  MCposition;

uniform vec3  LightPos;
uniform float Scale;

void main(void)
{
    vec3 ECposition = vec3 (gl_ModelViewMatrix * gl_Vertex);
    MCposition      = vec3 (gl_Vertex) * Scale;
    vec3 tnorm      = normalize(vec3 (gl_NormalMatrix * gl_Normal));
    LightIntensity  = dot(normalize(LightPos - ECposition), tnorm);
    LightIntensity *= 1.5;
    gl_Position     = ftransform();
}