// This is the file for the mvxParticleEngine

#include "mvx.h"

// psuedo 3D particles

mvxIsoParticleEngine::mvxIsoParticleEngine(mvxImage* p_image, D3DXVECTOR2 p_origin)
{
	mvxParticleImage = p_image;

	mvxOrigin = p_origin;

	mvxParticle = NULL;
	mvxFree     = NULL;

	mvxParticleCount = 0;
}

mvxIsoParticleEngine::~mvxIsoParticleEngine()
{

}

void mvxIsoParticleEngine::mvxDestroy()
{
	mvxParticleImage = NULL;

	while (mvxParticle)
	{
		mvxISO_PARTICLE* current = mvxParticle;
		mvxParticle = current->mvxNext;
		delete current;
	}

	while (mvxFree)
	{
		mvxISO_PARTICLE* current = mvxFree;
		mvxFree = current->mvxNext;
		delete current;
	}
}

void mvxIsoParticleEngine::mvxStart(D3DXVECTOR3 p_location, D3DXVECTOR3 p_velocity, D3DCOLOR p_color, D3DCOLOR p_fade, unsigned long p_life)
{
    // create a new particle
	mvxISO_PARTICLE *pPart, **ppPart;

    ppPart = &mvxParticle;
    
	// create new projectile
    if( mvxParticleCount < 1024 )
    {
        if( mvxFree )
        {
            pPart = mvxFree;
            mvxFree = pPart->mvxNext;
        }
        else
        {
            if( NULL == ( pPart = new mvxISO_PARTICLE ) )
                return;
        }

        pPart->mvxNext = mvxParticle;
        mvxParticle = pPart;
		mvxParticleCount++;

		pPart->mvxColor = p_color;
		pPart->mvxLocation = p_location;
		pPart->mvxVelocity = p_velocity;

		pPart->mvxLife  = p_life;

		pPart->mvxColor = p_color;
		pPart->mvxFade  = p_fade;
	}	
}

void mvxIsoParticleEngine::mvxUpdate(unsigned long p_timedelta)
{
	// move all particles do collision
	mvxISO_PARTICLE *pPart, **ppPart;

	ppPart = &mvxParticle;

	while( *ppPart )
    {
		pPart = *ppPart;

		pPart->mvxLocation += pPart->mvxVelocity;

		// gravity
		if (pPart->mvxVelocity.y != 0)
		{
			pPart->mvxVelocity.y += -.001f;
		}

		if (pPart->mvxLocation.y < 1)
		{
			pPart->mvxVelocity.y *= -0.75f;
		}
		if (pPart->mvxLocation.x > 10 || pPart->mvxLocation.x < 0)
		{
			pPart->mvxVelocity.x *= -1;
		}
		if (pPart->mvxLocation.z > 10 || pPart->mvxLocation.z < 0)
		{
			pPart->mvxVelocity.z *= -1;
		}

		pPart->mvxColor -= pPart->mvxFade;

		pPart->mvxLife--;

		if (pPart->mvxLife <= 0)
		{
			*ppPart = pPart->mvxNext;
			pPart->mvxNext = mvxFree;
			mvxFree = pPart;

			mvxParticleCount--;
			continue;		
		}

		ppPart = &pPart->mvxNext;
	}
}

void mvxIsoParticleEngine::mvxRenderParticles(mvxViewport* p_view)
{
	// convert x,y,z to x,y screen space
	// draw

	mvxISO_PARTICLE *pPart, **ppPart;

	ppPart = &mvxParticle;

	D3DXVECTOR2 screen;

	while( *ppPart )
    {
		pPart = *ppPart;

		// numbers are hardcoded, will be changed
		screen.x = mvxOrigin.x + (pPart->mvxLocation.x *  64 - pPart->mvxLocation.z * 64)-2;
		screen.y = mvxOrigin.y + (pPart->mvxLocation.x * -32 + pPart->mvxLocation.z * -32 + pPart->mvxLocation.y * - 224)-2; 

		mvxParticleImage->mvxRenderThis(NULL, NULL, NULL, NULL, &(screen - p_view->mvxLocation), pPart->mvxColor);

		ppPart = &pPart->mvxNext;
	}
}

void mvxIsoParticleEngine::mvxEmitter(D3DXVECTOR3 p_location, D3DXVECTOR3 p_initvector, D3DXVECTOR3 p_offset, D3DCOLOR p_color, unsigned long p_maxlife, unsigned long p_count)
{
	while (p_count--)
	{
		D3DXVECTOR3 vect = p_initvector;
		D3DXVECTOR3 offset = p_offset;

		offset.x *= (((float)(rand()%100)) / 100.0f) - .5f;
		offset.y *= (((float)(rand()%100)) / 100.0f) - .5f;
		offset.z *= (((float)(rand()%100)) / 100.0f) - .5f;

		vect = p_initvector + offset;

		unsigned long life = p_maxlife;

		mvxStart(p_location, vect, p_color, D3DCOLOR_ARGB(1, 0, 0, 0), life);
	}
}


// Now for 2D particles

mvxParticleEngine2D::mvxParticleEngine2D()
{
	mvxParticleImage = NULL;

	mvxParticles = NULL;
	mvxParticlesFree = NULL;

	mvxParticleCount = 0;
}

mvxParticleEngine2D::~mvxParticleEngine2D()
{
	mvxDestroy();
}

void mvxParticleEngine2D::mvxDestroy()
{
	mvxParticleImage = NULL;

	while (mvxParticles)
	{
		mvxPARTICLE2D* current = mvxParticles;
		mvxParticles = current->mvxNext;
		delete current;
	}

	while (mvxParticlesFree)
	{
		mvxPARTICLE2D* current = mvxParticlesFree;
		mvxParticlesFree = current->mvxNext;
		delete current;
	}
}

void mvxParticleEngine2D::mvxStart(D3DXVECTOR2 p_point, D3DXCOLOR p_col, D3DXVECTOR2 p_velocity, float p_ang, bool p_fde, bool p_rot, D3DXCOLOR p_fdeamt, float p_rotamt)
{
    // create a new particle
	mvxPARTICLE2D *pPart, **ppPart;

    ppPart = &mvxParticles;
    
	// create new projectile
    if( mvxParticleCount < PARTICLE_MAX )
    {
        if( mvxParticlesFree )
        {
            pPart = mvxParticlesFree;
            mvxParticlesFree = pPart->mvxNext;
        }
        else
        {
            if( NULL == ( pPart = new mvxPARTICLE2D ) )
                return;
        }

        pPart->mvxNext = mvxParticles;
        mvxParticles = pPart;
		mvxParticleCount++;

		pPart->mvxAngle = p_ang;
		pPart->mvxLocation = p_point;
		pPart->mvxColor = p_col;
		pPart->mvxVelocity = p_velocity;
		pPart->mvxRotate = p_rot;
		pPart->mvxFade = p_fde;
		pPart->mvxFadeAmount = p_fdeamt;
		pPart->mvxRotateAmount = p_rotamt;
	}	
}

void mvxParticleEngine2D::mvxExplode(D3DXVECTOR2 p_point, D3DCOLOR p_col, float p_force, int p_count, bool p_fde, bool p_rot, D3DXCOLOR p_fdeamt, float p_rotamt)
{
	// create an explosion from this loc
	while (p_count > 0 && mvxParticleCount < PARTICLE_MAX)
	{
		float currangle;

		currangle = (float)(rand() % 360);
		currangle = ((currangle * D3DX_PI) / 180);

		float force2 = (float)((rand() % 100) / 100);

		float xv, yv;
		xv = (float)cos(currangle)*force2;
		yv = (float)sin(currangle)*force2;

		mvxStart(p_point, p_col, D3DXVECTOR2(xv, yv), -currangle, p_fde, p_rot, p_fdeamt, p_rotamt); 

		p_count--;
	}
}

void mvxParticleEngine2D::mvxUpdate(unsigned long p_timedelta)
{
	// translate all mvxParticles
	mvxPARTICLE2D *pPart, **ppPart;

	ppPart = &mvxParticles;

	while( *ppPart )
    {
		pPart = *ppPart;

		pPart->mvxLocation += pPart->mvxVelocity;

		if (pPart->mvxRotate)
		{
			pPart->mvxAngle += pPart->mvxRotateAmount;
		}

		if (pPart->mvxColor > mvxARGB(0,0,0,0))
		{
			if (rand() % 9 == 0)
				pPart->mvxColor -= pPart->mvxFadeAmount;
		}
		else
		{
			// Kill mvxPARTICLE2D
			*ppPart = pPart->mvxNext;
			pPart->mvxNext = mvxParticlesFree;
			mvxParticlesFree = pPart;

			mvxParticleCount--;
			continue;
		}

		// boundry detection
		if (pPart->mvxLocation.x < 0 || pPart->mvxLocation.x > 1024 ||
			pPart->mvxLocation.y < 0 || pPart->mvxLocation.y > 768)
		{
			// Kill mvxPARTICLE2D
			*ppPart = pPart->mvxNext;
			pPart->mvxNext = mvxParticlesFree;
			mvxParticlesFree = pPart;

			mvxParticleCount--;
		}
		else
		{
			ppPart = &pPart->mvxNext;
		}
	}
}

void mvxParticleEngine2D::mvxRender(mvxViewport* p_view)
{
	mvxPARTICLE2D *pPart, **ppPart;

	ppPart = &mvxParticles;

	while( *ppPart )
    {
		pPart = *ppPart;

		mvxParticleImage->mvxRenderThis(NULL, &mvxParticleImage->mvxScaling, &mvxParticleImage->mvxRotationCenter, pPart->mvxAngle, &(pPart->mvxLocation - p_view->mvxLocation), pPart->mvxColor);

		ppPart = &pPart->mvxNext;
	}
}