//Notice: this sample vMF shader is mainly for reference purposes, therefore 
//doesn't guarantee compilability or optimal performance. 

// Variables passed to fragment shader
varying vec3 LightPos; 
varying vec3 EyePos; 
varying vec3 n; 
varying vec3 t; 
varying vec3 b;  

// Varialbes passed in by the programe
uniform vec3 LightPosition; 
attribute vec3 Tangent;

// Vertex shader main function
void main( void ) 
{	 	
	// Standard transformation
	EyePos = vec3 (gl_ModelViewMatrix * gl_Vertex);
 	LightPos = vec3 (gl_ModelViewMatrix * vec4(LightPosition,0.0));
	
	gl_Position = ftransform(); 	
	gl_TexCoord[0] = gl_MultiTexCoord0; 

	// Vertex's local coordinate axis
	n = normalize(gl_NormalMatrix * gl_Normal);
 	t = normalize(gl_NormalMatrix * Tangent);
 	b = cross(n, t); 
}