carnivores2/mathematics.cpp

#include "Hunt.h"

Vector3d TraceA, TraceB, TraceNv;
int      TraceRes;




//====================================================
void NormVector(Vector3d& v, float Scale)
{
  double n;
  n=v.x*v.x + v.y*v.y + v.z*v.z;
  if (n<0.000000001) n=0.000000001;
  n=(double)Scale / sqrt(n);
  v.x=v.x*n; 
  v.y=v.y*n;  
  v.z=v.z*n;
}

float SGN(float f)
{ 
  if (f<0) return -1.f;
      else return  1.f;  
}

void DeltaFunc(float &a, float b, float d)
{
  if (b > a) {
    a+=d; if (a > b) a = b;
   } else {
    a-=d; if (a < b) a = b;    
   }
}


void MulVectorsScal(Vector3d& v1,Vector3d& v2, float& r)
{
  r = v1.x*v2.x + v1.y*v2.y + v1.z*v2.z;
}


void MulVectorsVect(Vector3d& v1, Vector3d& v2, Vector3d& r )
{
  r.x= v1.y*v2.z - v2.y*v1.z;
  r.y=-v1.x*v2.z + v2.x*v1.z;
  r.z= v1.x*v2.y - v2.x*v1.y;
}

Vector3d RotateVector(Vector3d& v)
{
  Vector3d vv;
  float vx = v.x * ca + v.z * sa;
  float vz = v.z * ca - v.x * sa;
  float vy = v.y;
  vv.x = vx;
  vv.y = vy * cb - vz * sb;
  vv.z = vz * cb + vy * sb;
  return vv;
}



Vector3d SubVectors( Vector3d& v1, Vector3d& v2 )
{
    Vector3d res;
    res.x = v1.x-v2.x;
    res.y = v1.y-v2.y;
    res.z = v1.z-v2.z;
    return res;
}

Vector3d AddVectors( Vector3d& v1, Vector3d& v2 )
{
    Vector3d res;
    res.x = v1.x+v2.x;
    res.y = v1.y+v2.y;
    res.z = v1.z+v2.z;
    return res;
}

float VectorLength(Vector3d v)
{
  return (float)sqrt(v.x*v.x + v.y*v.y + v.z*v.z);
}


int siRand(int R)
{
  return (rand() * (R * 2 +1)) / RAND_MAX - R;
}


int rRand(int r)
{ 
 if (!r) return 0;
 int res = rand() % (r+1);// / (RAND_MAX);
 //if (res > r) res = r;
 return res;
}



void CalcHitPoint(CLIPPLANE& C, Vector3d& a, Vector3d& b, Vector3d& hp)
{ 
  float SCLN,SCVN;
  Vector3d lv = SubVectors(b,a);
  NormVector(lv, 1.0);
  
  MulVectorsScal(a, C.nv, SCLN);
  MulVectorsScal(lv,C.nv, SCVN);
                  
  SCLN/=SCVN; SCLN=(float)fabs(SCLN);
  hp.x = a.x + lv.x * SCLN;
  hp.y = a.y + lv.y * SCLN;
  hp.z = a.z + lv.z * SCLN;  
}


float PointToVectorD(Vector3d A, Vector3d AB, Vector3d C)
{    
    Vector3d AC = SubVectors(C,A);
    Vector3d vm;
    MulVectorsVect(AB, AC, vm);
    return VectorLength(vm);
}


float Mul2dVectors(float vx, float vy, float ux, float uy)
{
  return vx*uy - ux*vy;
}


float FindVectorAlpha(float vx, float vy)
{
 float adx, ady, alpha, dalpha;

 adx=(float)fabs(vx); 
 ady=(float)fabs(vy); 

 alpha = pi / 4.f;
 dalpha = pi / 8.f;

 for (int i=1; i<=10; i++) {
   alpha=alpha-dalpha*SGN(Mul2dVectors(adx,ady, (float)cos(alpha), (float)sin(alpha)));
   dalpha/=2;
 }

 if (vx<0) if (vy<0) alpha+=pi; else alpha=pi-alpha;
      else if (vy<0) alpha=2.f*pi-alpha;
 
 return alpha;
}


void CheckBoundCollision(float &px, float &py, float cx, float cy, float oy, TBound *bound, int angle)
{
	float ppx=px-cx;
	float ppy=py-cy; 
	
	float ca = (float) cos(angle*pi / 2.f);
	float sa = (float) sin(angle*pi / 2.f);	
	float w,h;

	for (int o=0; o<8; o++) {

		if (bound[o].a<0) continue;
		if (bound[o].y2 + oy < PlayerY + 128) continue;
        if (bound[o].y1 + oy > PlayerY + 256) continue;       		

        float ccx = bound[o].cx*ca + bound[o].cy*sa;
	    float ccy = bound[o].cy*ca - bound[o].cx*sa;

	    if (angle & 1) {
         w = bound[o].b+2.f;
	     h = bound[o].a+2.f;
		} else {
	     w = bound[o].a+2.f;
	     h = bound[o].b+2.f;
		}

	    float dw = fabs(ppx - ccx) - w;
	    float dh = fabs(ppy - ccy) - h;

	    if ( (dw > 0) || (dh > 0) ) continue;

	    if (dw > dh) {	   
         px = cx+ccx + w * SGN(ppx-ccx);
		} else {
         py = cy+ccy + h * SGN(ppy-ccy);
		}
	}
}	



void CheckCollision(float &cx, float &cz)
{
   if (cx < 36*256) cx = 36*256;
   if (cz < 36*256) cz = 36*256;
   if (cx >980*256) cx =980*256;
   if (cz >980*256) cz =980*256;
   int ccx = (int)cx / 256;
   int ccz = (int)cz / 256;

   for (int z=-4; z<=4; z++)
    for (int x=-4; x<=4; x++) 
      if (OMap[ccz+z][ccx+x]!=255) {
        int ob = OMap[ccz+z][ccx+x];
        float CR = (float)MObjects[ob].info.Radius;
        
        float oz = (ccz+z) * 256.f + 128.f;
        float ox = (ccx+x) * 256.f + 128.f;

		float LandY = GetLandOH(ccx+x, ccz+z);

		if (!(MObjects[ob].info.flags & ofBOUND)) {
         if (MObjects[ob].info.YHi + LandY < PlayerY + 128) continue;
         if (MObjects[ob].info.YLo + LandY > PlayerY + 256) continue;
		}

		if (MObjects[ob].info.flags & ofBOUND) {          
			CheckBoundCollision(cx, cz, ox, oz, LandY, MObjects[ob].bound, ((FMap[ccz+z][ccx+x] >> 2) & 3)  );
		} 
		  else
		if (MObjects[ob].info.flags & ofCIRCLE) {
         float r = (float) sqrt( (ox-cx)*(ox-cx) + (oz-cz)*(oz-cz) );
         if (r<CR) {
           cx = cx - (ox - cx) * (CR-r)/r;
           cz = cz - (oz - cz) * (CR-r)/r; }
		} else {
		   float r = (float) max( fabs(ox-cx) , fabs(oz-cz) );
           if (r<CR) {
		    if (fabs(ox-cx) > fabs(oz-cz) )
             cx = cx - (ox - cx) * (CR-r)/r;
		    else
             cz = cz - (oz - cz) * (CR-r)/r; 
		 }
		}
   }

   if (!TrophyMode) return;
   for (int c=0; c<ChCount; c++) {
	   float px = Characters[c].pos.x;
	   float pz = Characters[c].pos.z;
       float CR = DinoInfo[ Characters[c].CType ].Radius;
	   float r = (float) sqrt( (px-cx)*(px-cx) + (pz-cz)*(pz-cz) );
         if (r<CR) {
           cx = cx - (px - cx) * (CR-r)/r;
           cz = cz - (pz - cz) * (CR-r)/r;
         }       

   }

}



int TraceCheckPlane(Vector3d a, Vector3d b, Vector3d c)
{
  Vector3d pnv,hp;
  float sa, sb;
  MulVectorsVect(SubVectors(b,a), SubVectors(c,a), pnv);
  NormVector(pnv, 1.f);
  
  MulVectorsScal(SubVectors(TraceA,a), pnv, sa); 
  MulVectorsScal(SubVectors(TraceB,a), pnv, sb); 
  if (sa*sb>-1.f) return 0;

//========= calc hit point =======//
  float SCLN,SCVN;
    
  MulVectorsScal(SubVectors(TraceA,a), pnv, SCLN);
  MulVectorsScal(TraceNv, pnv, SCVN);
                  
  SCLN/=SCVN; SCLN=(float)fabs(SCLN);
  hp.x = TraceA.x + TraceNv.x * SCLN;
  hp.y = TraceA.y + TraceNv.y * SCLN;
  hp.z = TraceA.z + TraceNv.z * SCLN;  

  Vector3d vm;
  MulVectorsVect( SubVectors(b,a), SubVectors(hp,a), vm); 
  MulVectorsScal( vm, pnv, sa); if (sa<0) return 0;

  MulVectorsVect( SubVectors(c,b), SubVectors(hp,b), vm); 
  MulVectorsScal( vm, pnv, sa); if (sa<0) return 0;

  MulVectorsVect( SubVectors(a,c), SubVectors(hp,c), vm); 
  MulVectorsScal( vm, pnv, sa); if (sa<0) return 0;
  

  if (VectorLength(SubVectors(hp, TraceA)) < 
      VectorLength(SubVectors(TraceB, TraceA)) ) {
      TraceB = hp;
      return 1; }

  return 0;
}


void TraceModel(int xx, int zz, int o)
{
    TModel *mptr = MObjects[o].model;  
    v[0].x = xx * 256.f + 128.f;
    v[0].z = zz * 256.f + 128.f;
    v[0].y = (float)(HMapO[zz][xx]) * ctHScale;

    v[0].y+=700.f;    
    if (PointToVectorD(TraceA, TraceNv, v[0]) >1400.f) return;
    v[0].y-=700.f;

    float malp = (float)((FMap[zz][xx] >> 2) & 7) * 2.f*pi / 8.f;

    float ca = (float)cos(malp);
    float sa = (float)sin(malp);

    for (int vv=0; vv<mptr->VCount; vv++) {
      rVertex[vv].x = mptr->gVertex[vv].x * ca + mptr->gVertex[vv].z * sa  + v[0].x;
      rVertex[vv].y = mptr->gVertex[vv].y + v[0].y;
      rVertex[vv].z = mptr->gVertex[vv].z * ca - mptr->gVertex[vv].x * sa  + v[0].z;
    }
    
    for (int f=0; f<mptr->FCount; f++) {
      TFace *fptr = &mptr->gFace[f];
      if (fptr->Flags & (sfOpacity + sfTransparent) ) continue;
      v[0] = rVertex[fptr->v1];
      v[1] = rVertex[fptr->v2];
      v[2] = rVertex[fptr->v3];
      if (TraceCheckPlane(v[0], v[1], v[2]) )           
       TraceRes = tresModel;
    }
}




void TraceCharacter(int c)
{
  TCharacter *cptr = &Characters[c];

  if (PointToVectorD(TraceA, TraceNv, cptr->pos) > 1024.f) return;  
  
  TModel *mptr = cptr->pinfo->mptr;
  CreateChMorphedModel(cptr);   
  float ca = (float)cos(-cptr->alpha + pi / 2.f);
  float sa = (float)sin(-cptr->alpha + pi / 2.f);
  for (int vv=0; vv<mptr->VCount; vv++) {
      rVertex[vv].x = mptr->gVertex[vv].x * ca + mptr->gVertex[vv].z * sa  + cptr->pos.x;
      rVertex[vv].y = mptr->gVertex[vv].y + cptr->pos.y;
      rVertex[vv].z = mptr->gVertex[vv].z * ca - mptr->gVertex[vv].x * sa  + cptr->pos.z;
    }

  for (int f=0; f<mptr->FCount; f++) {
      TFace *fptr = &mptr->gFace[f];
      if (fptr->Flags & (sfOpacity + sfTransparent) ) continue;
      v[0] = rVertex[fptr->v1];
      v[1] = rVertex[fptr->v2];
      v[2] = rVertex[fptr->v3];
      if (TraceCheckPlane(v[0], v[1], v[2]) ) { 
		  TraceRes = tresChar; ShotDino = c; 
		  if (fptr->Flags & sfMortal) TraceRes |= 0x8000;
	  }
	      
    }
}


void FillVGround(Vector3d &v, int xx, int zz)
{
  v.x = xx*256.f; 
  v.z = zz*256.f;  
  v.y = (float)HMap[zz][xx]*ctHScale;
}


void FillWGround(Vector3d &v, int xx, int zz)
{
  v.x = xx*256.f; 
  v.z = zz*256.f;  
  v.y = (float)WaterList[ WMap[zz][xx] ].wlevel*ctHScale;
}


int  TraceLook(float ax, float ay, float az,
               float bx, float by, float bz)
{   
   TraceA.x = ax; TraceA.y = ay; TraceA.z = az;
   TraceB.x = bx; TraceB.y = by; TraceB.z = bz;

   TraceNv =  SubVectors(TraceB, TraceA);   
   
   Vector3d TraceNvP;

   TraceNvP = TraceNv; 
   TraceNvP.y = 0;

   NormVector(TraceNv, 1.0f);   
   NormVector(TraceNvP, 1.0f);   
   ObjectsOnLook=0;
   
   int axi = (int)(ax/256.f);
   int azi = (int)(az/256.f);

   int bxi = (int)(bx/256.f);
   int bzi = (int)(bz/256.f);

   int xm1 = min(axi, bxi) - 2;
   int xm2 = max(axi, bxi) + 2;
   int zm1 = min(azi, bzi) - 2;
   int zm2 = max(azi, bzi) + 2;

//======== trace ground model and static objects ============//   
   for (int zz=zm1; zz<=zm2; zz++)
    for (int xx=xm1; xx<=xm2; xx++) {
      if (xx<2 || xx>1010) continue;
      if (zz<2 || zz>1010) continue;

      BOOL ReverseOn = (FMap[zz][xx] & fmReverse);
      
      FillVGround(v[0], xx, zz);      
      FillVGround(v[1], xx+1, zz);    
      if (ReverseOn) FillVGround(v[2], xx, zz+1);
                else FillVGround(v[2], xx+1, zz+1);       
      if (TraceCheckPlane(v[0], v[1], v[2])) return 1;

      if (ReverseOn) { v[0] = v[2]; FillVGround(v[2], xx+1, zz+1); } 
                else { v[1] = v[2]; FillVGround(v[2], xx, zz+1);   }     
      if (TraceCheckPlane(v[0], v[1], v[2])) return 1;

	  int o = OMap[zz][xx];
	  if ( o!=255) {		        
		float s1,s2;
        v[0].x = xx * 256.f + 128.f;
        v[0].z = zz * 256.f + 128.f;        
        v[0].y = TraceB.y;		
		MulVectorsScal( SubVectors(v[0], TraceB), TraceNv, s1); s1*=-1;
		v[0].y = TraceA.y;		
		MulVectorsScal( SubVectors(v[0], TraceA), TraceNv, s2);

		if (s1>0 && s2>0)
        if (PointToVectorD(TraceA, TraceNvP, v[0]) < 180.f) {
		    ObjectsOnLook++;
            if (MObjects[o].info.Radius > 32)	ObjectsOnLook++;
		}
	  }
	}

   return 0;
}



int  TraceShot(float  ax, float  ay, float az,
               float &bx, float &by, float &bz)
{   
   TraceA.x = ax; TraceA.y = ay; TraceA.z = az;
   TraceB.x = bx; TraceB.y = by; TraceB.z = bz;

   TraceNv =  SubVectors(TraceB, TraceA);   
   NormVector(TraceNv, 1.0f);
   TraceRes = -1;

   int axi = (int)(ax/256.f);
   int azi = (int)(az/256.f);

   int bxi = (int)(bx/256.f);
   int bzi = (int)(bz/256.f);

   int xm1 = min(axi, bxi) - 2;
   int xm2 = max(axi, bxi) + 2;
   int zm1 = min(azi, bzi) - 2;
   int zm2 = max(azi, bzi) + 2;

//======== trace ground model and static objects ============//   
   for (int zz=zm1; zz<=zm2; zz++)
    for (int xx=xm1; xx<=xm2; xx++) {
      if (xx<2 || xx>1010) continue;
      if (zz<2 || zz>1010) continue;

      BOOL ReverseOn = (FMap[zz][xx] & fmReverse);
      
      FillVGround(v[0], xx, zz);      
      FillVGround(v[1], xx+1, zz);    
      if (ReverseOn) FillVGround(v[2], xx, zz+1);
                else FillVGround(v[2], xx+1, zz+1);       
      if (TraceCheckPlane(v[0], v[1], v[2])) TraceRes = tresGround;

      if (ReverseOn) { v[0] = v[2]; FillVGround(v[2], xx+1, zz+1); } 
                else { v[1] = v[2]; FillVGround(v[2], xx, zz+1);   }     
      if (TraceCheckPlane(v[0], v[1], v[2])) TraceRes = tresGround;

	  if ( (FMap[zz][xx] & fmWaterA)>0) {
         FillWGround(v[0], xx, zz);      
         FillWGround(v[1], xx+1, zz);    
		 FillWGround(v[2], xx+1, zz+1);       
		 if (TraceCheckPlane(v[0], v[1], v[2])) TraceRes = tresWater;
		 v[1] = v[2]; FillWGround(v[2], xx, zz+1);
		 if (TraceCheckPlane(v[0], v[1], v[2])) TraceRes = tresWater;
	  }

      if (OMap[zz][xx] !=255)
        TraceModel(xx, zz, OMap[zz][xx]);
    }

//======== trace characters ============//   
   for (int c=0; c<ChCount; c++) 
     TraceCharacter(c);

   float l;
   if ((TraceRes & 0xFF)==tresChar) l = 32.f; else l=16.f;
   bx = TraceB.x - TraceNv.x * l;
   by = TraceB.y - TraceNv.y * l;
   bz = TraceB.z - TraceNv.z * l;

   return TraceRes;
}




void InitClips2()
{   
   ClipA.v1.x = - (float)sin(pi/4-0.11); // 0.741
   ClipA.v1.y = 0;
   ClipA.v1.z =   (float)cos(pi/4-0.11); // 0.820
   ClipA.v2.x = 0; ClipA.v2.y = 1; ClipA.v2.z = 0;
   MulVectorsVect(ClipA.v1, ClipA.v2, ClipA.nv);

   ClipC.v1.x = + (float)sin(pi/4-0.11);
   ClipC.v1.y = 0;
   ClipC.v1.z =   (float)cos(pi/4-0.11);
   ClipC.v2.x = 0; ClipC.v2.y =-1; ClipC.v2.z = 0;
   MulVectorsVect(ClipC.v1, ClipC.v2, ClipC.nv);


   ClipB.v1.x = 0;
   ClipB.v1.y =   (float)sin(pi/5-.02);
   ClipB.v1.z =   (float)cos(pi/5-.02);
   ClipB.v2.x = 1; ClipB.v2.y = 0; ClipB.v2.z = 0;
   MulVectorsVect(ClipB.v1, ClipB.v2, ClipB.nv);

   ClipD.v1.x = 0;
   ClipD.v1.y = - (float)sin(pi/5-.02);
   ClipD.v1.z =   (float)cos(pi/5-.02);
   ClipD.v2.x =-1; ClipD.v2.y = 0; ClipD.v2.z = 0;
   MulVectorsVect(ClipD.v1, ClipD.v2, ClipD.nv);

   ClipZ.v1.x = 0; ClipZ.v1.y = 1; ClipZ.v1.z = 0;
   ClipZ.v2.x = 1; ClipZ.v2.y = 0; ClipZ.v2.z = 0;   
   MulVectorsVect(ClipZ.v1, ClipZ.v2, ClipZ.nv);

}



void InitClips()
{   
//	float XFOV = atan(CameraW , VideoCX); //1.6
//	float YFOV = atan(CameraH , VideoCY);
	float xx = (VideoCX+1) / (CameraW);
	float yy = (VideoCY+2) / (CameraH);
	float LX = sqrt(1.0 + xx * xx);
	float LY = sqrt(1.0 + yy * yy);

   ClipA.v1.x = - (float)xx / LX;
   ClipA.v1.y = 0;
   ClipA.v1.z =   (float)1 / LX;
   ClipA.v2.x = 0; ClipA.v2.y = 1; ClipA.v2.z = 0;
   MulVectorsVect(ClipA.v1, ClipA.v2, ClipA.nv);

   ClipC.v1.x = + (float)xx / LX;
   ClipC.v1.y = 0;
   ClipC.v1.z =   (float)1 / LX;
   ClipC.v2.x = 0; ClipC.v2.y =-1; ClipC.v2.z = 0;
   MulVectorsVect(ClipC.v1, ClipC.v2, ClipC.nv);


   ClipB.v1.x = 0;
   ClipB.v1.y =   (float)yy / LY;
   ClipB.v1.z =   (float)1  / LY;
   ClipB.v2.x = 1; ClipB.v2.y = 0; ClipB.v2.z = 0;
   MulVectorsVect(ClipB.v1, ClipB.v2, ClipB.nv);

   ClipD.v1.x = 0;
   ClipD.v1.y = - (float)yy / LY;
   ClipD.v1.z =   (float)1  / LY;
   ClipD.v2.x =-1; ClipD.v2.y = 0; ClipD.v2.z = 0;
   MulVectorsVect(ClipD.v1, ClipD.v2, ClipD.nv);

   ClipZ.v1.x = 0; ClipZ.v1.y = 1; ClipZ.v1.z = 0;
   ClipZ.v2.x = 1; ClipZ.v2.y = 0; ClipZ.v2.z = 0;   
   MulVectorsVect(ClipZ.v1, ClipZ.v2, ClipZ.nv);

   ClipW.nv.x =  0;
   ClipW.nv.y = cb;
   ClipW.nv.z = sb;

}





void CalcLights(TModel* mptr)
{
	int VCount = mptr->VCount;
	int FCount = mptr->FCount;
    int FUsed;
	float c;
	Vector3d norms[1024];
	Vector3d a, b, nv, rv;
    Vector3d slight;
	slight.x =-Sun3dPos.x;
	slight.y =-Sun3dPos.y/2;
	slight.z =-Sun3dPos.z;


	NormVector(slight, 1.0f);

    for (int f=0; f<FCount; f++) {
		int v1 = mptr->gFace[f].v1;
		int v2 = mptr->gFace[f].v2;
		int v3 = mptr->gFace[f].v3;

		a.x = mptr->gVertex[v2].x - mptr->gVertex[v1].x;
		a.y = mptr->gVertex[v2].y - mptr->gVertex[v1].y;
		a.z = mptr->gVertex[v2].z - mptr->gVertex[v1].z;

		b.x = mptr->gVertex[v3].x - mptr->gVertex[v1].x;
		b.y = mptr->gVertex[v3].y - mptr->gVertex[v1].y;
		b.z = mptr->gVertex[v3].z - mptr->gVertex[v1].z;
		
		MulVectorsVect(a, b, norms[f]);
		NormVector(norms[f], 1.0f);
	}

	for (int VT=0; VT<4; VT++) {
		float ca = (float)cos (VT * pi / 2);
		float sa = (float)sin (VT * pi / 2);
	for (int v=0; v<VCount; v++) {
		FUsed = 0;
		nv.x=0; nv.y=0; nv.z=0;
		for (f=0; f<FCount; f++) 
		  if (!(mptr->gFace[f].Flags & sfDoubleSide) )
			if (mptr->gFace[f].v1 == v || mptr->gFace[f].v2 == v || mptr->gFace[f].v3 == v ) 
			{ FUsed++;  nv = AddVectors(nv, norms[f]); }	

		if (!FUsed) mptr->VLight[VT][v] = 0; 
		else {
           NormVector(nv, 1.0f);
		   rv.y = nv.y;
		   rv.x = nv.x * sa + nv.z * ca;
		   rv.z = nv.z * sa - nv.x * ca;
           MulVectorsScal(rv, slight, c);		   
		   c = c * 64;
		   //if (c>64) c=64;
		   //if (c<-64) c=-64;
		   mptr->VLight[VT][v] = c;
		}  
	}
	}
}


/*
void CalcGouraud(TModel* mptr, Vecto3d *nvs[])
{
	int VCount = mptr->VCount;
	int FCount = mptr->FCount;
    int FUsed;
	float c;
	Vector3d norms[1024];
	Vector3d a, b, nv, rv;
    Vector3d slight;
	slight.x =-Sun3dPos.x;
	slight.y =-Sun3dPos.y;
	slight.z =-Sun3dPos.z;

	NormVector(slight, 1.0f);

    for (int f=0; f<FCount; f++) {
		int v1 = mptr->gFace[f].v1;
		int v2 = mptr->gFace[f].v2;
		int v3 = mptr->gFace[f].v3;

		a.x = mptr->gVertex[v2].x - mptr->gVertex[v1].x;
		a.y = mptr->gVertex[v2].y - mptr->gVertex[v1].y;
		a.z = mptr->gVertex[v2].z - mptr->gVertex[v1].z;

		b.x = mptr->gVertex[v3].x - mptr->gVertex[v1].x;
		b.y = mptr->gVertex[v3].y - mptr->gVertex[v1].y;
		b.z = mptr->gVertex[v3].z - mptr->gVertex[v1].z;
		
		MulVectorsVect(a, b, norms[f]);
		NormVector(norms[f], 1.0f);
	}
	
	for (int v=0; v<VCount; v++) {
		FUsed = 0;
		nv.x=0; nv.y=0; nv.z=0;
		for (f=0; f<FCount; f++) 
		  if (!(mptr->gFace[f].Flags & sfDoubleSide) )
			if (mptr->gFace[f].v1 == v || mptr->gFace[f].v2 == v || mptr->gFace[f].v3 == v ) 
			{ FUsed++;  nv = AddVectors(nv, norms[f]); }	

		if (!FUsed) mptr->VLight[0][v] = 0; 
		else {
           NormVector(nv, 1.0f);		   
           MulVectorsScal(nv, slight, c);
		   if (c<0) c=0; c=(c-0.5)*2;
		   c=c*c*c;
		   c = c * 98;
		   if (c>96) c=96;
		   if (c<-96) c=-96;
		   mptr->VLight[0][v] = c;
		}  
	
	}
}
*/


void CalcGouraud(TModel* mptr, Vector3d *nvs)
{
	int VCount = mptr->VCount;	
	float c;		
    Vector3d slight;
	slight.x =-Sun3dPos.x;
	slight.y =-Sun3dPos.y;
	slight.z =-Sun3dPos.z;

	NormVector(slight, 1.0f);

	for (int v=0; v<VCount; v++) {		
         MulVectorsScal(nvs[v], slight, c);
		 if (c<0) c=0; c=(c-0.5)*2;
		 c=c*c*c;
		 c = c * 96;
		 if (c>96) c=96;
		 if (c<-64) c=-64;
		 mptr->VLight[0][v] = c;
	}  	
}



void CalcNormals(TModel* mptr, Vector3d *nvs)
{
	int VCount = mptr->VCount;
	int FCount = mptr->FCount;    
	float c;	
	Vector3d a, b, nv, rv;    	
	FillMemory(nvs,   3*4*VCount, 0);

    for (int f=0; f<FCount; f++) {
		if (mptr->gFace[f].Flags & sfDoubleSide) continue;
		int v1 = mptr->gFace[f].v1;
		int v2 = mptr->gFace[f].v2;
		int v3 = mptr->gFace[f].v3;

		a.x = mptr->gVertex[v2].x - mptr->gVertex[v1].x;
		a.y = mptr->gVertex[v2].y - mptr->gVertex[v1].y;
		a.z = mptr->gVertex[v2].z - mptr->gVertex[v1].z;

		b.x = mptr->gVertex[v3].x - mptr->gVertex[v1].x;
		b.y = mptr->gVertex[v3].y - mptr->gVertex[v1].y;
		b.z = mptr->gVertex[v3].z - mptr->gVertex[v1].z;
		
		MulVectorsVect(a, b, nv);
		NormVector(nv, 1000.0f);
		nvs[v1]=AddVectors(nvs[v1], nv); 
		nvs[v2]=AddVectors(nvs[v2], nv);
		nvs[v3]=AddVectors(nvs[v3], nv);
	}
	
	for (int v=0; v<VCount; v++) 
		NormVector(nvs[v], 1.0);		
}


/*
void CalcNormals(TModel* mptr, Vector3d *nvs)
{
	int VCount = mptr->VCount;
	int FCount = mptr->FCount;
    int FUsed;
	float c;
	Vector3d norms[1024];
	Vector3d a, b, nv, rv;
    Vector3d slight;
	slight.x =-Sun3dPos.x;
	slight.y =-Sun3dPos.y;
	slight.z =-Sun3dPos.z;

	NormVector(slight, 1.0f);

    for (int f=0; f<FCount; f++) {
		int v1 = mptr->gFace[f].v1;
		int v2 = mptr->gFace[f].v2;
		int v3 = mptr->gFace[f].v3;

		a.x = mptr->gVertex[v2].x - mptr->gVertex[v1].x;
		a.y = mptr->gVertex[v2].y - mptr->gVertex[v1].y;
		a.z = mptr->gVertex[v2].z - mptr->gVertex[v1].z;

		b.x = mptr->gVertex[v3].x - mptr->gVertex[v1].x;
		b.y = mptr->gVertex[v3].y - mptr->gVertex[v1].y;
		b.z = mptr->gVertex[v3].z - mptr->gVertex[v1].z;
		
		MulVectorsVect(a, b, norms[f]);
		NormVector(norms[f], 1.0f);
	}
	
	for (int v=0; v<VCount; v++) {
		FUsed = 0;
		nv.x=0; nv.y=0; nv.z=0;
		for (f=0; f<FCount; f++) 
		  if (!(mptr->gFace[f].Flags & sfDoubleSide) )
			if (mptr->gFace[f].v1 == v || mptr->gFace[f].v2 == v || mptr->gFace[f].v3 == v ) 
			{ FUsed++;  nv = AddVectors(nv, norms[f]); }	
        
		if (!FUsed) { nv.x=0; nv.y=1; nv.z=0; }
        NormVector(nv, 1.0f);		   
        nvs[v] = nv;			
	}
} */



void CalcPhongMapping(TModel* mptr, Vector3d *nv) 
{
    Vector3d l,v,m, tx, ty, tv;
	float x,y;
	l.x =-Sun3dPos.x;
	l.y =-Sun3dPos.y;
	l.z =-Sun3dPos.z;

	tv.z = 0;
	tv.x = 1;
	tv.y = 1;
	
    NormVector(l, 1.0f);
	for (int i=0; i<mptr->VCount; i++) {		
		v.x = mptr->gVertex[i].x;
		v.y = mptr->gVertex[i].y;
		v.z = mptr->gVertex[i].z;
		NormVector(v, 1.0f);
		m = AddVectors(l, v);				
		NormVector(m, 1.0f);				
		

		if (l.z < 0) MulVectorsVect(m, tv, tx); 
		        else MulVectorsVect(m, v, tx); 

		NormVector(tx, 1.0f);		
		MulVectorsVect(m, tx, ty); NormVector(ty, 1.0f);
		MulVectorsScal(tx, nv[i], x);
		MulVectorsScal(ty, nv[i], y);
		PhongMapping[i].x = 128 + x *127;
		PhongMapping[i].y = 128 + y *127;
	}    
}


void CalcEnvMapping(TModel* mptr, Vector3d *nv) 
{
    Vector3d l,v,m, tx, ty;
	float x,y,s;
	float cc = cos((PlayerX + PlayerZ) / 500);
	float ss = sin((PlayerX + PlayerZ) / 500);
	tx.x = cc; tx.y = 0.0f; tx.z =-ss;
	ty.x = ss; ty.y = 0.0f; ty.z = cc;

	tx = RotateVector(tx);
	ty = RotateVector(ty);

    NormVector(l, 1.0f);
	for (int i=0; i<mptr->VCount; i++) {
		v.x = mptr->gVertex[i].x;
		v.y = mptr->gVertex[i].y;
		v.z = mptr->gVertex[i].z;
		MulVectorsScal(v, nv[i], s);
		m = nv[i];
		NormVector(m, s*2);
		m = AddVectors(m, v);
		NormVector(m, 1.0f);
		
		MulVectorsScal(tx, m, x);
		MulVectorsScal(ty, m, y);
		PhongMapping[i].x = 128 + x * 122;
		PhongMapping[i].y = 128 + y * 122;
	}    
}



void CalcBoundBox(TModel* mptr, TBound *bound)
{
	float x1, x2, y1, y2, z1, z2;
	BOOL first;

	for (int o=0; o<8; o++) {
		first = TRUE;
		bound[o].a=-1;
	

	  for (int v=0; v<mptr->VCount; v++) {		
		TPoint3d p = mptr->gVertex[v];
		if (p.hide) continue;
		if (p.owner!=o) continue;

		if (first) {
			x1 = p.x-1.0f;	x2 = p.x+1.0f;
	        y1 = p.y-1.0f;	y2 = p.y+1.0f;
	        z1 = p.z-1.0f;	z2 = p.z+1.0f;
			first = FALSE;
		}

		if (p.x < x1) x1=p.x;
		if (p.x > x2) x2=p.x;

		if (p.y < y1) y1=p.y;
		if (p.y > y2) y2=p.y;

		if (p.z < z1) z1=p.z;
		if (p.z > z2) z2=p.z;
	  }

	  if (first) continue;

	  x1-=72.f;
	  x2+=72.f;
	  z1-=72.f;
	  z2+=72.f;

	  bound[o].y1 = y1;
	  bound[o].y2 = y2;
	  bound[o].cx = (x1+x2) / 2;
	  bound[o].cy = (z1+z2) / 2;
	  bound[o].a  = (x2-x1) / 2;
	  bound[o].b  = (z2-z1) / 2;

	}

}