gistfile1.glsl

// cube definition
attribute vec4 vCubePosition;
attribute vec4 vCubeColor;
attribute vec3 vFaceNormal;

// color WHAT is this?
varying vec4 fColor;

// textures
attribute vec2 v2TexturesCoord;
varying vec2 fTexCoord;

uniform vec3 theta;

// Phong model
uniform vec4 ambientProduct, diffuseProduct, specularProduct;
uniform mat4 modelViewMatrix;
uniform mat4 projectionMatrix;
uniform vec4 lightPosition;
uniform float shininess;

void main()
{
    // Compute the sines and cosines of theta for each of
    //   the three axes in one computation.
    vec3 angles = radians( theta );
    vec3 c = cos( angles );
    vec3 s = sin( angles );

	/*
    // Remeber: thse matrices are column-major
    mat4 rx = mat4( 1.0,  0.0,  0.0, 0.0,
		            0.0,  c.x,  s.x, 0.0,
		            0.0, -s.x,  c.x, 0.0,
		            0.0,  0.0,  0.0, 1.0 );

    mat4 ry= mat4(  c.y, 0.0, -s.y, 0.0,
		            0.0, 1.0,  0.0, 0.0,
		            s.y, 0.0,  c.y, 0.0,
		            0.0, 0.0,  0.0, 1.0 );


    mat4 rz  = mat4( c.z, s.z, 0.0, 0.0,
		            -s.z, c.z, 0.0, 0.0,
		             0.0, 0.0, 1.0, 0.0,
		             0.0, 0.0, 0.0, 1.0 );
	*/


    vec3 pos = -(modelViewMatrix * vCubePosition).xyz;
    
    //fixed light postion
    vec3 light = lightPosition.xyz;
    vec3 L = normalize( light - pos );

    vec3 E = normalize( -pos );
    vec3 H = normalize( L + E );
    
    vec4 NN = vec4(vFaceNormal,0);

    // Transform vertex normal into eye coordinates
    vec3 N = normalize( (modelViewMatrix*NN).xyz);

    // Compute terms in the illumination equation
    vec4 ambient = ambientProduct;

    float Kd = max( dot(L, N), 0.0 );
    // vec4  diffuse = Kd * diffuseProduct;
    vec4  diffuse = diffuseProduct;

    float Ks = pow( max(dot(N, H), 0.0), shininess );
    // vec4  specular = Ks * specularProduct;
    vec4 specular = specularProduct;
    
    if( dot(L, N) < 0.0 ) {
		specular = vec4(0.0, 0.0, 0.0, 1.0);
    } 

    // Phong model
    fColor = ambient + diffuse + specular;
	fColor.a = 1.0;
    
    fTexCoord = v2TexturesCoord;
    // gl_Position = rz * ry * rx * vCubePosition;
    gl_Position = projectionMatrix * modelViewMatrix * vCubePosition;
    gl_Position.z = -gl_Position.z;
}