void main()
{
	vec4 lightAngle;
	vec4 pos;
	lightAngle = normalize(gl_Vertex-gl_ModelViewMatrixInverse*gl_LightSource[0].position);
	if (dot(gl_Normal,lightAngle.xyz)<0.0) {
		if (gl_Color.r>0.0) {
			pos = gl_Vertex+lightAngle*10.0;
		} else {
			pos = gl_Vertex;
		}
	} else {
		pos = vec4(0.0, 0.0, 0.0, 0.0);
	}
	gl_Position =  gl_ModelViewProjectionMatrix*pos;
}