// --------------------------------------------------------------------------
//
// Copyright (c) 2003 Thomas D. Marsh. All rights reserved.
//
// "SSC" is free software; you can redistribute it
// and/or use it and/or modify it under the terms of
// the "GNU General Public License" (GPL).
//
// --------------------------------------------------------------------------

#ifndef SSC_EXPLODE_H
#define SSC_EXPLODE_H

#include "draw.h"
#include "screen.h"
#include "common.h"
#include "object.h"

const float LIFE_TIME = 240;
const unsigned int TRIANGLE_RADIUS = 10;

namespace Global
{
	extern Coord3<double> normal;
}

struct ExploTriangle
{
	ExploTriangle() { }

	double radius;
	Coord3<double> mPosition, mForce, mRotation, mRotationSpeed;

	inline void draw()
	{
		glPushMatrix();
		  glTranslatef(mPosition.x, -mPosition.y, mPosition.z);
		  glRotated(mRotation.x, 1, 0, 0);
		  glRotated(mRotation.y, 0, 1, 0);
		  glRotated(mRotation.z, 0, 0, 1);

		  draw::startTriangles();
		    draw::trianglePoint(radius, 0, 0);
		    draw::trianglePoint(0, -radius/2, 0);
		    draw::trianglePoint(0, radius/2, 0);
		  draw::endTriangles();
		glPopMatrix();
	}

	inline void move(double dt)
	{
		mPosition += mForce * dt;
		mRotation += mRotationSpeed * dt;
	}
};

template <int NUM_TRIANGLES>
class Explosion
{
public:
	Explosion() : finished(false), age(0) {}
	bool finished;
	float age;
	float r, g, b;

	void init(ScreenObject &obj)
	{
		r = obj.r; g = obj.g; b = obj.b;
		for (unsigned int i=0; i < NUM_TRIANGLES; i++)
		{
			int n = (rand() % obj.radius);
			double d = RAD(rand() % 360);

			triangles[i].radius = TRIANGLE_RADIUS;
			triangles[i].mPosition.set(
					obj.mPosition.x + n * sin(d),
					obj.mPosition.y + n * cos(d),
					obj.mPosition.z + n * (sin(d*d)));
			triangles[i].mForce.set(
				obj.mVelocity.x + ((float) ((rand() % 101) - 50) / 10.0),
				obj.mVelocity.y + ((float) ((rand() % 101) - 50) / 10.0),
				obj.mVelocity.z + ((float) ((rand() % 101) - 50) / 10.0));
			triangles[i].mRotation.set(
					RAD(rand() % 360),
					RAD(rand() % 360),
					RAD(rand() % 360));
			triangles[i].mRotationSpeed.set(
					2*RAD(rand() % 360),
					2*RAD(rand() % 360),
					2*RAD(rand() % 360));
		}
	}

	inline void move(double dt)
	{
		for (unsigned int i=0; i < NUM_TRIANGLES; i++)
			triangles[i].move(dt);

		age += dt;
		if (age > LIFE_TIME)
			finished = true;
	}

	inline void draw()
	{
		glDisable(GL_LIGHTING);
		glDisable(GL_LIGHT0);
		glDisable(GL_LIGHT1);
		float a = 1.0 - age / LIFE_TIME;
		draw::setColor(r, g, b, a);
		for (unsigned int i=0; i < NUM_TRIANGLES; i++)
			triangles[i].draw();
		glEnable(GL_LIGHTING);
		glEnable(GL_LIGHT0);
		glEnable(GL_LIGHT1);
	}

private:
	ExploTriangle triangles[NUM_TRIANGLES];
};

#endif // SSC_EXPLODE_H