uniform vec3 cam_pos;
/* uniform vec4 diff_color, spec_color, ambient_color; */
uniform float spec_power;

varying vec4 light;
varying vec4 ambient, diff, spec;

void main (void)
{
  vec3 p = vec3(gl_ModelViewMatrix * gl_Vertex),
    v = normalize(cam_pos - p),
    n = normalize(gl_NormalMatrix * gl_Normal),
    r = reflect(-v, n),
    l = normalize(gl_LightSource[0].position.xyz - p);

  /* vec4 ambient, diff, spec; */
  /* gl_FrontMaterial.shininess */

  ambient = gl_FrontLightProduct[0].ambient;
  diff    = gl_FrontLightProduct[0].diffuse * max(dot(n, l), 0.0);
  diff    = clamp(diff, 0.0, 1.0);
  spec    = /* vec4(vec3(gl_FrontLightProduct[0].specular) */
    /*      *  */vec4(pow(max(dot(l, r), 0.0), 0.3 * spec_power))/* , 1) */;
  spec    = clamp(spec, 0.0, 1.0);

  light   = ambient + diff + spec;

  gl_TexCoord[0] = gl_MultiTexCoord0;
  gl_Position = gl_ModelViewProjectionMatrix * gl_Vertex;
}