/*
   render/lightenvironment.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/lightenvironment.h"
#include "render/gl.h"

namespace render
{

LightEnvironment::LightEnvironment()
{
	env_base_id = GL_LIGHT0;
	
	env_attenuation = 0.0005f;
	env_ambient_intensity = 0.1f;
	env_diffuse_intensity = 0.75f;
	env_specular_intensity = 0.75f;
}

LightEnvironment::~LightEnvironment()
{
	clear();
}

void LightEnvironment::clear()
{
	for (Container::iterator it = env_container.begin(); it != env_container.end(); ++it) {
		Light *light = (*it);
		delete light;
		(*it) = 0;
	}
	env_container.clear();
}

void LightEnvironment::add(Light *light)
{
	env_container.push_back(light);
}

void LightEnvironment::enable()
{
	int gl_light_id = env_base_id;
	for (Container::iterator it = env_container.begin(); it != env_container.end(); ++it) {
		//Light *light = (*it);
		gl::enable(gl_light_id);
		
		gl_light_id++;
	}
}

void LightEnvironment::disable()
{
	int gl_light_id = env_base_id;
	for (Container::iterator it = env_container.begin(); it != env_container.end(); ++it) {
		//Light *light = (*it);		
		gl::disable(gl_light_id);
		gl_light_id++;
	}
}

void LightEnvironment::draw(const math::Vector3f translate)
{
	GLfloat gl_light_location[4];
	GLfloat gl_ambient_light[4];
	GLfloat gl_diffuse_light[4];
	GLfloat gl_specular_light[4];

	int gl_light_id = env_base_id;
	
	for (Container::iterator it = env_container.begin(); it != env_container.end(); ++it) {
		Light *light = (*it);
		
		for (size_t i = 0; i < 3; i++) {
			gl_light_location[i] = light->location()[i] + translate[i];
			gl_ambient_light[i] = light->color()[i] * env_ambient_intensity;
			gl_diffuse_light[i] = light->color()[i] * env_diffuse_intensity;
			gl_specular_light[i] = light->color()[i] * env_specular_intensity;
		}	
		
		gl_light_location[3] = 1.0f;
		gl_ambient_light[3] = 1.0f;
		gl_diffuse_light[3] = 1.0f;
		gl_specular_light[3] = 1.0f;
		
		gl::light(gl_light_id, GL_POSITION, gl_light_location);
		gl::light(gl_light_id, GL_AMBIENT, gl_ambient_light);
		gl::light(gl_light_id, GL_DIFFUSE, gl_diffuse_light);
		gl::light(gl_light_id, GL_SPECULAR, gl_specular_light);
		
		// attenuation
		gl::light(gl_light_id, GL_CONSTANT_ATTENUATION, light->attenuation()[0]);
		gl::light(gl_light_id, GL_LINEAR_ATTENUATION, light->attenuation()[1]);
		gl::light(gl_light_id, GL_QUADRATIC_ATTENUATION, light->attenuation()[2]);

		
		gl_light_id++;
	}
}

void LightEnvironment::draw()
{
	draw(math::Vector3f());
}

} // namespace render