//
// Vertex shader for environment mapping with an
// equirectangular 2D texture
//
// Authors: John Kessenich, Randi Rost
//
// Copyright (c) 2002-2004 3Dlabs Inc. Ltd. 
//
// See 3Dlabs-License.txt for license information
//

varying vec3  Normal;
varying vec3  EyeDir;
varying float LightIntensity;

uniform vec3  LightPos;

void main(void) 
{
    gl_Position    = ftransform();
    Normal         = normalize(gl_NormalMatrix * gl_Normal);
    vec4 pos       = gl_ModelViewMatrix * gl_Vertex;
    EyeDir         = pos.xyz;
    LightIntensity = max(dot(normalize(LightPos - EyeDir), Normal), 0.0);
}