varying vec3 light_dir;
varying vec3 eyepos;
varying vec4 light;

uniform int NumEnabledLights;
uniform int show_Lights;

void main()
{
	vec4 tmp;

	tmp = gl_ModelViewMatrix * gl_Vertex;
	eyepos = vec3(tmp)/tmp.w;
	
	gl_TexCoord[0] = gl_MultiTexCoord0;
	gl_TexCoord[1] = gl_MultiTexCoord1;
	gl_TexCoord[2] = gl_MultiTexCoord2;
	gl_TexCoord[3] = gl_MultiTexCoord3;

	gl_TexCoord[0] = gl_TextureMatrix[0]*gl_TexCoord[0];
	gl_TexCoord[1] = gl_TextureMatrix[1]*gl_TexCoord[1];
	gl_TexCoord[2] = gl_TextureMatrix[2]*gl_TexCoord[2];
	gl_TexCoord[3] = gl_TextureMatrix[3]*gl_TexCoord[3];

	gl_Position = ftransform();

	vec3 eye;

	bool LocalViewer;

	LocalViewer = false;
	
	if (LocalViewer) eye = -normalize(eyepos);
	else eye = vec3(0.0, 0.0, 1.0);

	vec3 normal = vec3(0.0, 0.0, 1.0);
	
	normal = normalize(gl_NormalMatrix*normal);

	vec3 L0, L1, L2, L3, L4, L5, L6, L7, a0, a1, a2, a3, a4, a5, a6, a7;
	float d0, d1, d2, d3, d4, d5, d6;
	vec3 v;
	
	v = vec3(gl_ModelViewMatrix * gl_Vertex);
	
	a0 = gl_LightSource[0].position.xyz - v;
	a1 = gl_LightSource[1].position.xyz - v;
	a2 = gl_LightSource[2].position.xyz - v;
	a3 = gl_LightSource[3].position.xyz - v;
	a4 = gl_LightSource[4].position.xyz - v;
	a5 = gl_LightSource[5].position.xyz - v;
	a6 = gl_LightSource[6].position.xyz - v;
	a7 = gl_LightSource[7].position.xyz;

	L0 = normalize(a0);
	L1 = normalize(a1);
	L2 = normalize(a2);
	L3 = normalize(a3);
	L4 = normalize(a4);
	L5 = normalize(a5);
	L6 = normalize(a6);
	L7 = normalize(a7);

	d0 = length(a0);
	d1 = length(a1);
	d2 = length(a2);
	d3 = length(a3);
	d4 = length(a4);
	d5 = length(a5);
	d6 = length(a6);
	
	d0 = 1.0 / (	gl_LightSource[0].constantAttenuation +
			gl_LightSource[0].linearAttenuation * d0);
	d1 = 1.0 / (	gl_LightSource[1].constantAttenuation +
			gl_LightSource[1].linearAttenuation * d1);
	d2 = 1.0 / (	gl_LightSource[2].constantAttenuation +
			gl_LightSource[2].linearAttenuation * d2);
	d3 = 1.0 / (	gl_LightSource[3].constantAttenuation +
			gl_LightSource[3].linearAttenuation * d3);
	d4 = 1.0 / (	gl_LightSource[4].constantAttenuation +
			gl_LightSource[4].linearAttenuation * d4);
	d5 = 1.0 / (	gl_LightSource[5].constantAttenuation +
			gl_LightSource[5].linearAttenuation * d5);
	d6 = 1.0 / (	gl_LightSource[6].constantAttenuation +
			gl_LightSource[6].linearAttenuation * d6);
	
	light = vec4(0.0);
	if (NumEnabledLights >= 0)
		light += gl_FrontLightProduct[0].diffuse * max(dot(normal, L0), 0.0) * d0;
	if (NumEnabledLights >= 1)
		light += gl_FrontLightProduct[1].diffuse * max(dot(normal, L1), 0.0) * d1;
	if (NumEnabledLights >= 2)
		light += gl_FrontLightProduct[2].diffuse * max(dot(normal, L2), 0.0) * d2;
	if (NumEnabledLights >= 3)
		light += gl_FrontLightProduct[3].diffuse * max(dot(normal, L3), 0.0) * d3;
	if (NumEnabledLights >= 4)
		light += gl_FrontLightProduct[4].diffuse * max(dot(normal, L4), 0.0) * d4;
	if (NumEnabledLights >= 5)
		light += gl_FrontLightProduct[5].diffuse * max(dot(normal, L5), 0.0) * d5;
	if (NumEnabledLights >= 6)
		light += gl_FrontLightProduct[6].diffuse * max(dot(normal, L6), 0.0) * d6;
	if (all(equal(gl_FrontLightProduct[7].diffuse, vec4(0.0))))
		light += gl_FrontLightProduct[7].diffuse * max(dot(normal, L7), 0.0);
	light += gl_FrontLightProduct[7].ambient*gl_FrontMaterial.ambient;
	light += gl_LightModel.ambient * gl_FrontMaterial.ambient;
}