예제 #1
0
static int All_Box_Intersections(OBJECT *Object, RAY *Ray, ISTACK *Depth_Stack)
{
  int Intersection_Found;
  int Side1, Side2;
  DBL Depth1, Depth2;
  VECTOR IPoint;

  Increase_Counter(stats[Ray_Box_Tests]);

  Intersection_Found = false;

  if (Intersect_Box(Ray, ((BOX *)Object)->Trans, ((BOX *)Object)->bounds[0], ((BOX *)Object)->bounds[1], &Depth1, &Depth2, &Side1, &Side2))
  {
    if (Depth1 > DEPTH_TOLERANCE)
    {
      VEvaluateRay(IPoint, Ray->Initial, Depth1, Ray->Direction);

      if (Point_In_Clip(IPoint, Object->Clip))
      {
        push_entry_i1(Depth1,IPoint,Object,Side1,Depth_Stack);

        Intersection_Found = true;
      }
    }

    VEvaluateRay(IPoint, Ray->Initial, Depth2, Ray->Direction);

    if (Point_In_Clip(IPoint, Object->Clip))
    {
      push_entry_i1(Depth2,IPoint,Object,Side2,Depth_Stack);

      Intersection_Found = true;
    }
  }

  if (Intersection_Found)
  {
    Increase_Counter(stats[Ray_Box_Tests_Succeeded]);
  }

  return (Intersection_Found);
}
예제 #2
0
static int All_IsoSurface_Intersections(OBJECT* Object, RAY* Ray, ISTACK* Depth_Stack)
{
	ISOSURFACE * Isosrf = (ISOSURFACE *)Object;
	int Side1 = 0, Side2 = 0, itrace = 0, i_flg = 0;
	DBL Depth1 = 0.0, Depth2 = 0.0, len = 0.0;
	RAY New_Ray;
	VECTOR IPoint;
	VECTOR P, D;
	DBL tmax = 0.0, tmin = 0.0, tmp = 0.0;
	int i = 0 ; /* count of intervals in stack - 1      */
	int IFound = false;
	int begin = 0, end = 0;
	bool in_shadow_test = false;
	VECTOR VTmp;

	Increase_Counter(stats[Ray_IsoSurface_Bound_Tests]);

	in_shadow_test = ((Ray->Optimisiation_Flags & OPTIMISE_SHADOW_TEST) == OPTIMISE_SHADOW_TEST);

	if(Isosrf->container_shape)
	{
		if(Isosrf->Trans != NULL)
		{
			MInvTransPoint(New_Ray.Initial, Ray->Initial, Isosrf->Trans);
			MInvTransDirection(New_Ray.Direction, Ray->Direction, Isosrf->Trans);
			VLength(len, New_Ray.Direction);
			VInverseScaleEq(New_Ray.Direction, len);
			i_flg = Intersect_Sphere(&New_Ray, Isosrf->container.sphere.center, 
			                         (Isosrf->container.sphere.radius) * (Isosrf->container.sphere.radius),
			                         &Depth1, &Depth2);
			Depth1 = Depth1 / len;
			Depth2 = Depth2 / len;
		}
		else
		{
			i_flg = Intersect_Sphere(Ray, Isosrf->container.sphere.center, 
			                         (Isosrf->container.sphere.radius) * (Isosrf->container.sphere.radius), &Depth1, &Depth2);
		}
		Decrease_Counter(stats[Ray_Sphere_Tests]);
		if(i_flg)
			Decrease_Counter(stats[Ray_Sphere_Tests_Succeeded]);
	}
	else
	{
		i_flg = Intersect_Box(Ray, Isosrf->Trans, Isosrf->container.box.corner1, Isosrf->container.box.corner2,
		                      &Depth1, &Depth2, &Side1, &Side2);
	}

	if(Depth1 < 0.0)
		Depth1 = 0.0;

	if(i_flg)									/* IsoSurface_Bound_Tests */
	{
		Increase_Counter(stats[Ray_IsoSurface_Bound_Tests_Succeeded]);
		if(Isosrf->Trans != NULL)
		{
			MInvTransPoint(P, Ray->Initial, Isosrf->Trans);
			MInvTransDirection(D, Ray->Direction, Isosrf->Trans);
		}
		else
		{
			Assign_Vector(P, Ray->Initial);
			Assign_Vector(D, Ray->Direction);
		}
		Isosrf->Inv3 = 1;

		if(Isosrf->closed != false)
		{
			VEvaluateRay(VTmp, P, Depth1, D);
			tmp = Vector_IsoSurface_Function(Isosrf, VTmp);
			if(Depth1 > Isosrf->accuracy)
			{
				if(tmp < 0.0)					/* The ray hits the bounding shape */
				{
					VEvaluateRay(IPoint, Ray->Initial, Depth1, Ray->Direction);
					if(Point_In_Clip(IPoint, Object->Clip))
					{
						push_entry_i1(Depth1, IPoint, Object, Side1, Depth_Stack);
						IFound = true;
						itrace++;
						Isosrf->Inv3 *= -1;
					}
				}
			}
			else
			{
				if(tmp < (Isosrf->max_gradient * Isosrf->accuracy * 4.0))
				{
					Depth1 = Isosrf->accuracy * 5.0;
					VEvaluateRay(VTmp, P, Depth1, D);
					if(Vector_IsoSurface_Function(Isosrf, VTmp) < 0)
						Isosrf->Inv3 = -1;
					/* Change the sign of the function (IPoint is in the bounding shpae.)*/
				}
				VEvaluateRay(VTmp, P, Depth2, D);
				if(Vector_IsoSurface_Function(Isosrf, VTmp) < 0.0)
				{
					VEvaluateRay(IPoint, Ray->Initial, Depth2, Ray->Direction);
					if(Point_In_Clip(IPoint, Object->Clip))
					{
						push_entry_i1(Depth2, IPoint, Object, Side2, Depth_Stack);
						IFound = true;
					}
				}
			}
		}

		/*  METHOD 2   by R. Suzuki */
		tmax = Depth2 = min(Depth2, BOUND_HUGE);
		tmin = Depth1 = min(Depth2, Depth1);
		if((tmax - tmin) < Isosrf->accuracy)
			return (false);
		Increase_Counter(stats[Ray_IsoSurface_Tests]);
		if((Depth1 < Isosrf->accuracy) && (Isosrf->Inv3 == 1))
		{
			/* IPoint is on the isosurface */
			VEvaluateRay(VTmp, P, tmin, D);
			if(fabs(Vector_IsoSurface_Function(Isosrf, VTmp)) < (Isosrf->max_gradient * Isosrf->accuracy * 4.0))
			{
				tmin = Isosrf->accuracy * 5.0;
				VEvaluateRay(VTmp, P, tmin, D);
				if(Vector_IsoSurface_Function(Isosrf, VTmp) < 0)
					Isosrf->Inv3 = -1;
				/* change the sign and go into the isosurface */
			}
		}

		for (; itrace < Isosrf->max_trace; itrace++)
		{
			if(IsoSurface_Function_Find_Root(Isosrf, P, D, &tmin, &tmax, in_shadow_test) == false)
				break;
			else
			{
				VEvaluateRay(IPoint, Ray->Initial, tmin, Ray->Direction);
				if(Point_In_Clip(IPoint, Object->Clip))
				{
					push_entry_i1(tmin, IPoint, Object, 0 /*Side1*/, Depth_Stack);
					IFound = true;
				}
			}
			tmin += Isosrf->accuracy * 5.0;
			if((tmax - tmin) < Isosrf->accuracy)
				break;
			Isosrf->Inv3 *= -1;
		}

		if(IFound)
			Increase_Counter(stats[Ray_IsoSurface_Tests_Succeeded]);
	}

	return (IFound);
}