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

#include <sstream>
#include <iomanip>

#include "core/core.h"
#include "model/fragment.h"
#include "model/material.h"
#include "model/model.h"
#include "render/render.h"
#include "render/textures.h"
#include "render/draw.h"
#include "render/dust.h"
#include "render/gl.h"

namespace render
{

size_t Stats::tris = 0;
size_t Stats::quads = 0;

void Stats::clear()
{
	tris = 0;
	quads = 0;
}

math::Vector3f v0(1, -1, 1);
math::Vector3f v1(1,  1, 1);
math::Vector3f v2(-1,  1,  1);
math::Vector3f v3(-1, -1,  1);

math::Vector3f v4(1, -1, -1);
math::Vector3f v5(1,  1, -1);
math::Vector3f v6(-1,  1,  -1);
math::Vector3f v7(-1, -1,  -1);

const float drawdistance = 128.0f;
const float drawfxdistance = 64.0f;
core::Zone *zone = 0;

// function to test flags
inline bool flag_is_set(unsigned int const spawnflags, unsigned int const flag) {
	return ((spawnflags & flag) == flag);
}

/* ----- Default Entity shapes ------------------------------------- */

void draw_sphere(math::Color const & color, float radius)
{	
	//gl::push();
	gl::scale(radius, radius, radius);
	gl::color(color);

	size_t index = 0;
	size_t count = (model::SPHERESEGMENTS)*2;

	// draw body
	for (int j=0; j < (model::SPHERESEGMENTS-1)/2; j++) {
		glDrawArrays(gl::QuadStrip, index, count);
		index += count;
		Stats::quads += count/2-1;
	}

	//gl::pop();
}

void draw_sphere_inside(math::Color const & color, float radius)
{	
	//gl::push();
	gl::scale(radius, radius, radius);
	gl::color(color);

	size_t index = (model::SPHERESEGMENTS) * (model::SPHERESEGMENTS-1);
	size_t count = (model::SPHERESEGMENTS)*2;

	// draw body
	for (int j=0; j < (model::SPHERESEGMENTS-1)/2; j++) {
		glDrawArrays(gl::QuadStrip, index, count);
		index += count;
		Stats::quads += count/2-1;
	}

	//gl::pop();
}

void draw_entity_sphere(core::Entity *entity)
{
	if ((entity->type() == core::Entity::Globe) && !flag_is_set(entity->flags(), core::Entity::Bright)) {
		gl::disable(GL_LIGHT0);	// disable camera light, level light only
		
		core::EntityGlobe *globe = (core::EntityGlobe *)entity;
		if (globe->render_texture) {
			Textures::bind(globe->render_texture);
			gl::enable(GL_TEXTURE_2D);
		}
	}

	draw_sphere(entity->color(), entity->radius());

	if ((entity->type() == core::Entity::Globe) && !flag_is_set(entity->flags(), core::Entity::Bright)) {
		core::EntityGlobe *globe = (core::EntityGlobe *)entity;
		if (globe->render_texture) {
			gl::disable(GL_TEXTURE_2D);
		}
		gl::enable(GL_LIGHT0);
	}
}

void draw_entity_cube(core::Entity *entity)
{
	float radius = entity->radius();
	gl::scale(radius, radius, radius);

	gl::color(entity->color());
	gl::begin(gl::Quads);
	
	// top
	gl::normal(0,0,1);
	gl::vertex(v0);
	gl::vertex(v1);
        gl::vertex(v2);
	gl::vertex(v3);

	// bottom
	gl::normal(0,0, -1);
	gl::vertex(v7);
	gl::vertex(v6);
        gl::vertex(v5);
	gl::vertex(v4);
	
	// sides
	gl::normal(1,0,0);
	gl::vertex(v1);
    	gl::vertex(v0);
        gl::vertex(v4);
        gl::vertex(v5);

	gl::normal(-1,0,0);
        gl::vertex(v3);
    	gl::vertex(v2);
        gl::vertex(v6);
        gl::vertex(v7);

	gl::normal(0,1,0);
	gl::vertex(v2);
    	gl::vertex(v1);
        gl::vertex(v5);
        gl::vertex(v6);

	gl::normal(0,-1,0);
	gl::vertex(v0);
    	gl::vertex(v3);
        gl::vertex(v7);
        gl::vertex(v4);

	gl::end();
}

void draw_entity_diamond(core::Entity *entity)
{
	float radius = entity->radius()/2;

	gl::color(entity->color());

	gl::begin(gl::TriangleFan );
	gl::normal(0, 0 , 1);
	gl::vertex(0, 0, radius);

	gl::normal(1, 0 ,0);
	gl::vertex(radius, 0.0f, 0.0f);
	gl::normal(0, 1, 0);
	gl::vertex(0.0f, radius, 0.0f);
	gl::normal(-1, 0 ,0);
	gl::vertex(-radius, 0.0f, 0.0f);
	gl::normal(0, -1, 0);
	gl::vertex(0.0f, -radius, 0.0f);
	gl::normal(1, 0 ,0);
	gl::vertex(radius, 0.0f, 0.0f);

	gl::end();

	gl::begin(gl::TriangleFan);
	gl::normal(0, 0 , -1);
	gl::vertex(0, 0, -radius);
	
	gl::normal(1, 0,  0);
	gl::vertex(radius, 0.0f, 0.0f);

	gl::normal(0, -1, 0);
	gl::vertex(0.0f, -radius, 0.0f);

	gl::normal(-1, 0 ,0);
	gl::vertex(-radius, 0.0f, 0.0f);

	gl::normal(0, 1, 0);
	gl::vertex(0.0f, radius, 0.0f);

	gl::normal(1, 0 ,0);
	gl::vertex(radius, 0.0f, 0.0f);

	gl::end();

	gl::begin(gl::Lines);

	gl::vertex(radius, 0, 0);
	gl::vertex(2* radius, 0, 0);

	gl::vertex(0, radius, 0);
	gl::vertex(0, 2* radius, 0);

	gl::vertex(0, 0, radius);
	gl::vertex(0, 0, 2 * radius);

	gl::vertex(-radius, 0, 0);
	gl::vertex(-2 * radius, 0, 0);
	
	gl::vertex(0, -radius, 0);
	gl::vertex(0, -2 * radius, 0);

	gl::vertex(0, 0, -radius);
	gl::vertex(0, 0, -2 * radius);

	gl::end();
}

void draw_entity_axis(core::Entity *entity)
{
	using namespace render;
	float r = entity->radius();
	gl::begin(gl::Lines);
	gl::color(1.0f, 0.0f, 0.0f);
	gl::vertex(r,0.0f,0.0f);
	gl::color(entity->color());
	gl::vertex(-r,0.0f,0.0f);

	gl::vertex(0.0f,r/2,0.0f);
	gl::vertex(0.0f,-r/2,0.0f);

	gl::vertex(0.0f,0.0f,r);
	gl::vertex(0.0f,0.0f,-r);
	gl::end();
}

/* ----- model fragments ------------------------------------------- */

void draw_fragment(model::Fragment *fragment, bool draw_details)
{
	size_t index = fragment->index();

	size_t vertex_count = fragment->structural_size();
	if (draw_details)
		vertex_count += fragment->detail_size();

	switch (fragment->type()) {
		case model::Fragment::Triangles:
			glDrawArrays(gl::Triangles, index, vertex_count);
			Stats::tris += vertex_count / 3;
			break;

		case model::Fragment::Quads:
			glDrawArrays(gl::Quads, index, vertex_count);
			Stats::quads += vertex_count / 4;
			break;
	}
}

void draw_model_fragments(core::Entity *entity)
{
	using namespace model;

	Model *model = entity->model();
	if (!model)
		return;

	// default material, lighted and geometry color
	unsigned int material = Material::None;

	bool use_color_array = true;	// glEnableClientState(GL_COLOR_ARRAY) is set
	bool use_light = true;		// gl::disable(GL_LIGHTING) is set

	float thrust = 0;
	if (entity->type() == core::Entity::Controlable) {
		thrust = static_cast<core::EntityControlable *>(entity)->thrust();
	}

	for (Model::Fragments::iterator fit = model->fragments().begin(); fit != model->fragments().end(); fit++) {

		Fragment *fragment = (*fit);

		if (fragment->material() != material) {
			material = fragment->material();

			if (material & Material::Engine) {

				if (use_color_array) {
					glDisableClientState(GL_COLOR_ARRAY);
					use_color_array = false;
				}

				gl::color(thrust, 0.0f, 0.0f);

			} else if (material & Material::Tertiary) {
				if (use_color_array) {
					use_color_array = false;
					glDisableClientState(GL_COLOR_ARRAY);
				}

				math::Color color;

				if ((material & Material::Tertiary) == Material::Tertiary) {
					for (size_t i = 0; i < 3; i++)
						color[i] = (entity->color()[i] + entity->color_second()[i]) / 2;

				} else if ((material & Material::Secondary) == Material::Secondary) {
					color.assign(entity->color_second());

				} if ((material & Material::Primary) == Material::Primary) {
					color.assign(entity->color());
				}

				if (material & Material::Dark)
					color *= 0.5f;

				gl::color(color);
		
			} else {
				if (!use_color_array) {
					glEnableClientState(GL_COLOR_ARRAY);
					use_color_array = true;
				}
			}

			if (material & Material::Light) {
				if (use_light) {
					gl::disable(GL_LIGHTING);
					use_light = false;
				}
			} else if (material & Material::Engine) {
				if (use_light) {
					gl::disable(GL_LIGHTING);
					use_light = false;
				}
			} else {
				if (!use_light) {
					gl::enable(GL_LIGHTING);
					use_light = true;
				}
			}
		}

		draw_fragment(fragment, entity->state()->detailvisible());
	}

	if (!use_light) {
		gl::enable(GL_LIGHTING);
	}

	if (!use_color_array) {
		glEnableClientState(GL_COLOR_ARRAY);
	}
}


/* ----- Render passes --------------------------------------------- */

/* calculate entity visibility */
void pass_prepare(float seconds)
{
	using namespace model;

	// reset light state
	gl::disable(GL_LIGHT1);

	// get the current OpenGL transformation matrices
	GLdouble gl_projection_matrix[16];
	GLdouble gl_model_matrix[16];
	GLint gl_viewport[4];

	glGetDoublev(GL_PROJECTION, gl_projection_matrix);
	glGetDoublev(GL_MODELVIEW, gl_model_matrix);
	glGetIntegerv(GL_VIEWPORT, gl_viewport);

	for (core::Zone::Content::iterator it = zone->content().begin(); it != zone->content().end(); it++) {
		core::Entity *entity = (*it);
		
		// load entity models and light flare textures
		if (!entity->model() && entity->modelname().size()) {
			entity->entity_model = Model::load(entity->modelname());
						
			if (!entity->model()) {
				entity->entity_modelname.clear();
				entity->entity_radius = 0.25;
			} else {
				// set entity radius to model radius
				entity->entity_radius = entity->entity_model->radius();

				for (Model::Lights::iterator lit = entity->model()->lights().begin(); lit != entity->model()->lights().end(); lit++) {
					Light *light = (*lit);

					// load light texture
					// FIXME optimize
					std::stringstream flarename;
					flarename << "bitmaps/fx/flare" << std::setfill('0') << std::setw(2) << light->flare();
					light->render_texture = Textures::load(flarename.str());
				}

				for(Model::Engines::iterator eit = entity->model()->engines().begin(); eit != entity->model()->engines().end(); eit++) {
					Engine *engine = (*eit);

					if (!engine->flare()) engine->engine_flare = 1;

					// load engine texture
					// FIXME optimize
					std::stringstream flarename;
					flarename << "bitmaps/fx/flare" << std::setfill('0') << std::setw(2) << engine->flare();
					engine->render_texture = Textures::load(flarename.str());
				}

				for (Model::Flares::iterator flit = entity->model()->flares().begin(); flit != entity->model()->flares().end(); flit++) {
					Flare *flare = (*flit);

					// load flare texture
					// FIXME optimize
					std::stringstream flarename;
					flarename << "bitmaps/fx/flare" << std::setfill('0') << std::setw(2) << flare->flare();
					flare->render_texture = Textures::load(flarename.str());
				}
			}
		}

		if (!entity->state()) {
			entity->entity_clientstate = new core::ClientState(entity);
		}

		entity->state()->state_visible = false;	
		entity->state()->state_detailvisible = false;
		entity->state()->state_targetable = false;

		// calculate visibility for entities with models
		if (entity->model()) {

			entity->state()->state_visible = false;
			float dq = math::distancesquared(Camera::eye(), entity->location());
	
			if (dq <= drawfxdistance*drawfxdistance*entity->model()->radius())  {
				// entites within drawing distance
				entity->state()->state_visible = true;
				entity->state()->state_detailvisible = true;
			} else if (dq <= drawdistance*drawdistance*entity->model()->radius())  {
				// entities within drawdistance
				entity->state()->state_visible = true;
				entity->state()->state_detailvisible = false;
			}

		} else 	{
			entity->state()->state_visible = true;	

			if (entity->type() == core::Entity::Globe) { 
				core::EntityGlobe *globe = (core::EntityGlobe *) entity;

				if (flag_is_set(globe->flags(), core::Entity::Bright)) {

					// bright globes set level light
					GLfloat light_position[4];
					GLfloat diffuse_light[4];
					GLfloat ambient_light[] = { 0.0f, 0.0f, 0.0f, 1.0f };
					GLfloat specular_light[] = { 0.2f, 0.2f, 0.2f, 1.0f };
	
					for (size_t i=0; i <3; i++) {
						light_position[i] = globe->location()[i] - render::Camera::eye()[i];
						diffuse_light[i] = globe->color()[i] * 0.4;
					}
					light_position[3] = 1.0f;
					diffuse_light[3] = 1.0f;
					
					glLightfv(GL_LIGHT1, GL_POSITION, light_position);
					glLightfv(GL_LIGHT1, GL_AMBIENT, ambient_light);
					glLightfv(GL_LIGHT1, GL_DIFFUSE, diffuse_light);
					glLightfv(GL_LIGHT1, GL_SPECULAR, specular_light);
					gl::enable(GL_LIGHT1);
				} else {
		
					// load globe textures
					// FIXME optimize
					if (globe->texture().size()) {
						std::stringstream texname;
						texname << "textures/" << globe->texture();
						globe->render_texture = Textures::load(texname.str());
					}
				}
			}		
		}
	}
}

/* Draw entities without model */
void draw_pass_default()
{
	for (core::Zone::Content::iterator it = zone->content().begin(); it != zone->content().end(); it++) {
		core::Entity *entity = (*it);

		// draw entities without model
		if (!entity->model()) {
			gl::push();
			gl::translate(entity->state()->location() - Camera::eye());
			gl::multmatrix(entity->state()->axis());

			if (flag_is_set(entity->flags(), core::Entity::Bright)) {
				gl::disable(GL_LIGHTING);
			}
		
			switch(entity->shape()) {
	
				case core::Entity::Sphere:
					draw_entity_sphere(entity);
					break;
					
				case core::Entity::Diamond:
					draw_entity_diamond(entity);
					break;

				case core::Entity::Axis:
					draw_entity_axis(entity);
					break;

				case core::Entity::Cube:
				
			default:
				draw_entity_cube(entity);
				break;
			}

			if (flag_is_set(entity->flags(), core::Entity::Bright)) {
				gl::enable(GL_LIGHTING);	
			}
				
			gl::pop();

		} else if (r_bbox->value()) {

			// draw bounding box if requested
			model::Model *model = entity->model();
			gl::color(entity->color());

			gl::push();
			gl::translate(entity->state()->location() - Camera::eye());
			gl::multmatrix(entity->state()->axis());
			
			// top
			gl::begin(gl::LineLoop);
			gl::vertex(model->model_maxbbox.x, model->model_maxbbox.y, model->model_maxbbox.z);
			gl::vertex(model->model_minbbox.x, model->model_maxbbox.y, model->model_maxbbox.z);
			gl::vertex(model->model_minbbox.x, model->model_minbbox.y, model->model_maxbbox.z);
			gl::vertex(model->model_maxbbox.x, model->model_minbbox.y, model->model_maxbbox.z);
			gl::end();

			// bottom
			gl::begin(gl::LineLoop);
			gl::vertex(model->model_maxbbox.x, model->model_maxbbox.y, model->model_minbbox.z);
			gl::vertex(model->model_minbbox.x, model->model_maxbbox.y, model->model_minbbox.z);
			gl::vertex(model->model_minbbox.x, model->model_minbbox.y, model->model_minbbox.z);
			gl::vertex(model->model_maxbbox.x, model->model_minbbox.y, model->model_minbbox.z);
			gl::end();
		
			gl::begin(gl::Lines);
			gl::vertex(model->model_maxbbox.x, model->model_maxbbox.y, model->model_maxbbox.z);
			gl::vertex(model->model_maxbbox.x, model->model_maxbbox.y, model->model_minbbox.z);
			gl::vertex(model->model_minbbox.x, model->model_maxbbox.y, model->model_maxbbox.z);
			gl::vertex(model->model_minbbox.x, model->model_maxbbox.y, model->model_minbbox.z);
			gl::vertex(model->model_minbbox.x, model->model_minbbox.y, model->model_maxbbox.z);
			gl::vertex(model->model_minbbox.x, model->model_minbbox.y, model->model_minbbox.z);
			gl::vertex(model->model_maxbbox.x, model->model_minbbox.y, model->model_maxbbox.z);
			gl::vertex(model->model_maxbbox.x, model->model_minbbox.y, model->model_minbbox.z);
			gl::end();

			gl::pop();
			
		}
	}
}

/* draw model geometry fragments */
void draw_pass_model_fragments()
{
	for (core::Zone::Content::iterator it = zone->content().begin(); it != zone->content().end(); it++) {
		core::Entity *entity = (*it);

		if (entity->model() && entity->state()->visible()) {
			gl::push();
			gl::translate(entity->state()->location()  - Camera::eye());
			gl::multmatrix(entity->state()->axis());

			draw_model_fragments(entity);

			gl::pop();
		}
	}
}

/* draw model lights and engines */
void draw_pass_model_fx(float elapsed)
{
	const size_t count = 8; // number of engine trail particles

	float t = 0.0f;
	float u = 0.0f;
	float a = 0.0f;
	float light_size = 0.0f;
	float engine_size = 0.0f;
	float trail_size = 0.0f;
	
	math::Vector3f quad[4];
	math::Vector3f location;
	math::Vector3f offset;
	math::Color color;

	model::Light *light;
	model::Flare *flare;
	model::Engine *engine;

	math::Axis flare_axis;

	size_t circle_texture = Textures::load("bitmaps/fx/circle00");
	size_t current_texture = Textures::bind("bitmaps/fx/flare00");

	gl::enable(GL_TEXTURE_2D);
	gl::begin(gl::Quads);

	for (core::Zone::Content::iterator it = zone->content().begin(); it != zone->content().end(); it++) {
		core::Entity *entity = (*it);

		if (entity->model() &&  entity->state() && entity->state()->detailvisible()) {

			// draw model lights		
			for (model::Model::Lights::iterator lit = entity->model()->lights().begin(); lit != entity->model()->lights().end(); lit++) {
				light = (*lit);

				// strobe frequency
				t = 1.0f;
				if (light->strobe())
					t = (core::application()->time() - light->offset() - entity->state()->fuzz()) * light->frequency();
				if ((!light->strobe()) || (( t - floorf(t)) <= light->time())) {
					location.assign(entity->state()->location()  - Camera::eye() + (entity->state()->axis() * light->location()));
					light_size = 0.0625 * light->radius();
	
					if (current_texture != light->texture()) {
						gl::end();
						current_texture = Textures::bind(light->texture());
						gl::begin(gl::Quads);
					}

					if (light->entity()) {
						color.assign(entity->color());
					} else {
						color.assign(light->color());
					}
					color.a = 0.8;
					gl::color(color);
					
					glTexCoord2f(0,1);
					gl::vertex(location + (Camera::axis().up() - Camera::axis().left()) * light_size);
					glTexCoord2f(0,0);
					gl::vertex(location + (Camera::axis().up() + Camera::axis().left()) * light_size);
					glTexCoord2f(1,0);
					gl::vertex(location + (Camera::axis().up() * -1 + Camera::axis().left()) * light_size);
					glTexCoord2f(1,1);
					gl::vertex(location + (Camera::axis().up() * -1 - Camera::axis().left()) * light_size);
					Stats::quads++;
				}
			}
			
			// draw flares
			for (model::Model::Flares::iterator flit = entity->model()->flares().begin(); flit != entity->model()->flares().end(); flit++) {				
				flare = (*flit);
				
				// strobe frequency
				t = 1.0f;
				if (flare->strobe())
					t = (core::application()->time() + entity->state()->fuzz() - flare->offset()) * flare->frequency();

				if ((!flare->strobe()) || (( t - floorf(t)) <= flare->time())) {
					flare_axis.assign(entity->state()->axis());
					if (flare->angle())
						flare_axis.change_direction(flare->angle());

					location.assign(entity->state()->location()  - Camera::eye() + (entity->state()->axis() * flare->location()));
					light_size = 0.0625 * flare->radius();
	
					if (current_texture != flare->texture()) {
						gl::end();
						current_texture = Textures::bind(flare->texture());
						gl::begin(gl::Quads);
					}

					if (flare->entity()) {
						color.assign(entity->color());
					} else {
						color.assign(flare->color());
					}

					// FIXME Camera::axis().forward() should be the vector flare_location - camera_eye
					a = dotproduct(flare_axis.forward(), Camera::axis().forward());
					if (a < -0.1f) {
						color.a = -a - 0.1f;
						gl::color(color);
						
						glTexCoord2f(0,1);
						gl::vertex(location + (flare_axis.up() + flare_axis.left()) * light_size);
						glTexCoord2f(0,0);
						gl::vertex(location + (flare_axis.up() - flare_axis.left()) * light_size);
						glTexCoord2f(1,0);
						gl::vertex(location + (flare_axis.up() * -1 - flare_axis.left()) * light_size);
						glTexCoord2f(1,1);
						gl::vertex(location + (flare_axis.up() * -1 + flare_axis.left()) * light_size);
	
						Stats::quads++;
					}
					
				}
			}

			// draw model engines for Controlable entities
			if ((entity->type() == core::Entity::Controlable) && entity->model()->engines().size()) {

				u = static_cast<core::EntityControlable *>(entity)->thrust();

				if (u > 0) {
					t = entity->state()->state_engine_trail_offset;
					t += elapsed * 4.0f * u;
				
					if (t > 1.0f)
						t -= 1.0f;
					math::clamp(t, 0.0f, 1.0f);
					entity->state()->state_engine_trail_offset = t;

					for(model::Model::Engines::iterator eit = entity->model()->engines().begin(); eit != entity->model()->engines().end(); eit++) {
	
						engine = (*eit);
	
						location.assign(entity->state()->location()  - Camera::eye() + (entity->state()->axis() * engine->location()));
						engine_size = 0.0625 * engine->radius();
						color.assign(engine->color());
						color.a = 0.9f * u;
	
						if (current_texture != engine->texture() ) {
							gl::end();
							current_texture = Textures::bind(engine->texture());
							gl::begin(gl::Quads);
						}
	
						quad[0].assign(entity->state()->axis().up() - entity->state()->axis().left());
						quad[1].assign(entity->state()->axis().up() + entity->state()->axis().left());
						quad[2].assign(entity->state()->axis().up() * -1 + entity->state()->axis().left());
						quad[3].assign(entity->state()->axis().up() * -1 - entity->state()->axis().left());
	
						gl::color(color);					
						glTexCoord2f(0,1);
						gl::vertex(location + quad[0] * engine_size);
						glTexCoord2f(0,0);
						gl::vertex(location + quad[1] * engine_size);
						glTexCoord2f(1,0);
						gl::vertex(location + quad[2] * engine_size);
						glTexCoord2f(1,1);
						gl::vertex(location + quad[3] * engine_size);
						Stats::quads++;
	
						// draw the engine trail
						if (current_texture != circle_texture) {
							gl::end();
							current_texture = Textures::bind(circle_texture);
							gl::begin(gl::Quads);
						}
						color.assign(1.0f, 1.0f);
						offset.assign(entity->state()->axis().forward() * engine_size);

						if (t > 0)
							location -= offset * t;

						for (size_t i = count; i > 0; i--) {
							trail_size = engine_size * 0.8f * (0.4f + ((-t + (float) i) / (float) count) * 0.6f);
							color.a = (0.1f + ((-t + (float) i) / (float) count) * 0.7f) * u;
							gl::color(color);
							glTexCoord2f(0,1);
							gl::vertex(location + quad[0] * trail_size);
							glTexCoord2f(0,0);
							gl::vertex(location + quad[1] * trail_size);
							glTexCoord2f(1,0);
							gl::vertex(location + quad[2] * trail_size);
							glTexCoord2f(1,1);
							gl::vertex(location + quad[3] * trail_size);
							Stats::quads++;
	
	
							gl::color(color);
							glTexCoord2f(1,1);
							gl::vertex(location + quad[3] * trail_size);
							glTexCoord2f(1,0);
							gl::vertex(location + quad[2] * trail_size);
							glTexCoord2f(0,0);
							gl::vertex(location + quad[1] * trail_size);
							glTexCoord2f(0,1);
							gl::vertex(location + quad[0] * trail_size);
							Stats::quads++;

							location -= offset;
						}
					}
				}
			}
		}	
	}

	gl::end();
	gl::disable(GL_TEXTURE_2D);
}

void draw_pass_model_corona()
{
	if (!(r_radius && r_radius->value()))
		return;

	for (core::Zone::Content::iterator it = zone->content().begin(); it != zone->content().end(); it++) {
		core::Entity *entity = (*it);

		if (entity->model() && entity->state()->visible()) {
			gl::push();
			gl::translate(entity->state()->location()  - Camera::eye());
			math::Color color = entity->color();
			color.a = 0.25f;
			draw_sphere(color, entity->model()->radius());
			gl::pop();
		}
	}

}


/* Draw skysphere */
void draw_pass_sky()
{
	if (!(r_sky && r_sky->value()))
		return;

	if (!core::localplayer()->zone())
		return;

	if (!core::localplayer()->zone()->sky_texture() && core::localplayer()->zone()->sky().size()) {

		std::string texture_name("textures/env/");
		texture_name.append(core::localplayer()->zone()->sky());
		core::localplayer()->zone()->set_sky_texture(Textures::load(texture_name));

		if (!core::localplayer()->zone()->sky_texture())
			core::localplayer()->zone()->set_sky("");
	}

	Textures::bind(core::localplayer()->zone()->sky_texture());
	gl::enable(GL_TEXTURE_2D);
	gl::push();

	//gl::translate(Camera::eye());	
	draw_sphere_inside(math::Color(), 128);

	gl::pop();
	gl::disable(GL_TEXTURE_2D);
}

void draw_pass_spacegrid()
{
	if (!(r_grid && r_grid->value()))
		return;

	int gridsize = 32;
	float s = 1.0f / gridsize;
	float z = -4.0f;

	float dx =  Camera::target().x - floorf(Camera::target().x);
	float dy =  Camera::target().y - floorf(Camera::target().y);

	gl::push();
	gl::translate(Camera::target() - Camera::eye());
	gl::color(0,0, 1.0f);
	gl::normal(0, 0, 1.0f);

	gl::begin(gl::Lines);

	for (int i=-gridsize; i <= gridsize; i++) {
		gl::color(0,0, 0, 0);
		gl::vertex(i-dx, -gridsize-dy, z);
		gl::color(0,0, (gridsize-abs(i))*s, (gridsize-abs(i))*s);
		gl::vertex(i-dx, -dy, z );
		gl::vertex(i-dx, -dy ,z );
		gl::color(0,0, 0, 0);
		gl::vertex(i-dx, gridsize-dy, z);

		gl::vertex(-gridsize-dx, i-dy, z );
		gl::color(0,0, (gridsize-abs(i))*s, (gridsize-abs(i))*s);
		gl::vertex(-dx, i-dy, z);
		gl::vertex(-dx, i-dy, z);
		gl::color(0,0, 0, 0);
		gl::vertex(gridsize-dx, i-dy, z);
	}
	gl::end();

	gl::pop();
}

/* ----- Main draw routine ----------------------------------------- */

void draw(float seconds)
{
	zone = core::localplayer()->zone();
	if (!zone)
		return;
	
	Camera::frame(seconds);		
	Camera::draw(); // draw the current camera transformation

	// calculate client state
	pass_prepare(seconds);

	// enable wireframe mode if requested
	if (r_wireframe && r_wireframe->value()) {
		glPolygonMode(GL_FRONT, GL_LINE);
	} else {
		glPolygonMode(GL_FRONT, GL_FILL);
	}

	// set vertex array pointers	
	glVertexPointer(3, GL_FLOAT, 0, vertexarray->vertex());
	glNormalPointer(GL_FLOAT, 0, vertexarray->normal());
	glColorPointer(3, GL_FLOAT, 0, vertexarray->color());
	glTexCoordPointer(3, GL_FLOAT, 0, vertexarray->texture());

	// enable vertex arrays
	glEnableClientState(GL_VERTEX_ARRAY);
	glEnableClientState(GL_COLOR_ARRAY);
	glEnableClientState(GL_TEXTURE_COORD_ARRAY);
	glEnableClientState(GL_NORMAL_ARRAY);
	glDisableClientState(GL_COLOR_ARRAY);

	gl::enable(GL_DEPTH_TEST);	
	gl::depthmask(GL_FALSE);	// disable depth buffer writing

	draw_pass_sky();		// draw the skysphere

	
	gl::depthmask(GL_TRUE);		// enable writing to the depth buffer

	gl::enable(GL_CULL_FACE);	// enable culling
	gl::enable(GL_COLOR_MATERIAL);	// enable color tracking
	gl::enable(GL_LIGHTING);	
	//gl::enable(GL_RESCALE_NORMAL);	// rescale normals by the transformation matrix scale factor
	gl::enable(GL_NORMALIZE);
	
	draw_pass_default();		// draw entities without model
	
	gl::disable(GL_NORMALIZE);
	//gl::disable(GL_RESCALE_NORMAL);

	glEnableClientState(GL_COLOR_ARRAY);

	draw_pass_model_fragments();

	glDisableClientState(GL_COLOR_ARRAY);
	gl::disable(GL_LIGHTING);
	
	gl::enable(GL_BLEND);
	gl::depthmask(GL_FALSE);	// disable depth buffer writing
	
	draw_pass_spacegrid();		// draw the blue spacegrid
	Dust::draw();			// draw spacedust

	
	draw_pass_model_fx(seconds);		// draw entity lights and engines

	gl::enable(GL_LIGHTING);
	gl::enable(GL_RESCALE_NORMAL);

	draw_pass_model_corona();	// draw entity radius
	
	glDisableClientState(GL_VERTEX_ARRAY);
	glDisableClientState(GL_NORMAL_ARRAY);
	glDisableClientState(GL_TEXTURE_COORD_ARRAY);

	gl::disable(GL_RESCALE_NORMAL);
	gl::disable(GL_LIGHTING);
	gl::disable(GL_COLOR_MATERIAL);	// disable color tracking
	gl::disable(GL_CULL_FACE);	// disable culling
	
	gl::depthmask(GL_TRUE);	// enable depth buffer writing
	gl::disable(GL_DEPTH_TEST);	// disable depth buffer testing
	// GL_BLEND must be enabled for the GUI
}

// reset drawing parameters for a new localcontrol
void reset()
{
	Dust::reset();
}

}