/*
*   Simple textured fragment shader. Modulates texture color with 
*       lambertian shading.
*
*   Alexandri Zavodny, Fall 2010 
*       for CSE 40166/60166 Computer Graphics, University of Notre Dame
*/
uniform sampler2D tex;
varying vec3 dirToLight, theNormal;

void main()
{
    //grab the texture color...
    vec4 texColor = texture2D(tex, gl_TexCoord[0].st);

    //perform some simple lambertian shading...
    float lambertianIntensity = max(dot(normalize(theNormal), normalize(dirToLight)),0.0);

    //and modulate that with the texture color. et voila!
    gl_FragColor = vec4(lambertianIntensity*texColor.rgb, texColor.a) + vec4(0.1,0.1,0.1,0.0);
}