/*
   gl/sphere.cc
   This file is part of the Osirion project and is distributed under 
   the terms of the GNU General Public License version 2 
*/

#include "render/sphere.h"
#include "math/mathlib.h"

using math::Vector3f;
using math::Color;

namespace render {

const int segments = 33;

Sphere::Sphere(float r)
{
	radius = r;
		
	// TODO make global sine-cosine lists
	sintable = new float[segments];
	costable = new float[segments];
	float d = 2 * M_PI / (segments-1);

	for (int i=0; i < segments; i++) {
		sintable[i] = sin( d * (float) i );
		costable[i] = cos ( d * (float) i );
	}
}

Sphere::~Sphere()
{
	delete[] sintable;
	delete[] costable;
}

Sphere::Sphere(const Sphere &other) 
{
	(*this) = other;
}
	
Sphere& Sphere::operator=(const Sphere &other)
{
	sphere_color = other.sphere_color;
	radius = other.radius;
	return (*this);
}

void Sphere::draw()
{
	using namespace gl;

	float r = radius*sintable[1];
	//float h = radius*costable[1];
	
	gl::color(sphere_color);

	/*
	// draw top
	begin(Polygon);
	normal(0, 1, 0);
	for (int i = segments-1; i >= 0; i--) {
		v = Vector3f(r*costable[i], h, r*sintable[i]);
		n = v;
		n.normalize();
		normal(n);
		vertex(v);
	}
	end();

	// draw bottom
	begin(Polygon);
	normal(0, -1, 0);
	for (int i = 0; i< segments; i++) {
	//for (int i = segments-1; i >= 0; i--)
		v = Vector3f(r*costable[i], -h, r*sintable[i]);
		n = v;
		n.normalize();
		normal(n);
		vertex(v);
	}
	end();
	*/
	
	Vector3f v;
	Vector3f n;

	// draw body
	for (int j=0; j < segments-1; j++) {
		r = radius*sintable[j];
		float r1 = radius*sintable[j+1];
		
		begin(QuadStrip);
		v = Vector3f(r, radius*costable[j], 0);
		n = v;
		n.normalize();
		normal(n);
		vertex(v);

		v = Vector3f(r1, radius*costable[j+1], 0);
		n = v;
		n.normalize();
		normal(n);
		vertex(v);

		for (int i = segments-1; i >= 0; i--) {
			v = Vector3f(r*costable[i], radius*costable[j], r*sintable[i]);
			n = v;
			n.normalize();
			normal(n);
			vertex(v);
			
			v = Vector3f(r1*costable[i], radius*costable[j+1], r1*sintable[i]);
			n = v;
			n.normalize();
			normal(n);
			vertex(v);

			//vertex(r*costable[i-1], radius*costable[j], r*sintable[i-1]);
			//vertex(r1*costable[i-1], radius*costable[j+1], r1*sintable[i-1]);
		}
		end();
		
	}
}
	

}