Attachment 8080 Details for Bug 19653 – Self-contained example

Self-contained example

test.cpp (text/plain), 2.89 KB, created by Uroš Bizjak on 2005-01-27 08:35:20 UTC

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Creator: Uroš Bizjak

Created: 2005-01-27 08:35:20 UTC

Size: 2.89 KB

patch

obsolete

>#include <string.h>
>#include <math.h>
>
>typedef double DBL;
>
>typedef DBL VECTOR [3];
>
>typedef struct Ray_Struct RAY;
>
>struct Ray_Struct
>{
>  VECTOR Initial;
>  VECTOR Direction;
>  int Index;
>  unsigned long Optimisiation_Flags;
>};
>
>enum
>{
>	X = 0,
>	Y = 1,
>	Z = 2,
>	T = 3
>};
>
>typedef struct byte_xyz BYTE_XYZ;
>
>struct byte_xyz {
>  unsigned char x, y, z;
>};
>
>#define Assign_Vector(d,s)  memcpy((d),(s),sizeof(VECTOR))
>
>#define VCross(a,b,c) {(a)[X]=(b)[Y]*(c)[Z]-(b)[Z]*(c)[Y]; \
>                       (a)[Y]=(b)[Z]*(c)[X]-(b)[X]*(c)[Z]; \
>                       (a)[Z]=(b)[X]*(c)[Y]-(b)[Y]*(c)[X];}
>
>#define VDot(a, b, c) {a=(b)[X]*(c)[X]+(b)[Y]*(c)[Y]+(b)[Z]*(c)[Z];}
>
>#define VNormalizeEq(a) {DBL _tmp=1.0/sqrt((a)[X]*(a)[X]+(a)[Y]*(a)[Y]+(a)[Z]*(a)[Z]);(a)[X]*=_tmp;(a)[Y]*=_tmp;(a)[Z]*=_tmp;}
>
>#define VAddScaledEq(V, k, V2)  \
>  { (V)[X] += (k) * (V2)[X];    \
>    (V)[Y] += (k) * (V2)[Y];    \
>    (V)[Z] += (k) * (V2)[Z]; }
>
>static void VUnpack(VECTOR dest_vec, BYTE_XYZ * pack_vec)
>{
>  dest_vec[X] = ((double)pack_vec->x * (1./ 255.))*2.-1.;
>  dest_vec[Y] = ((double)pack_vec->y * (1./ 255.))*2.-1.;
>  dest_vec[Z] = ((double)pack_vec->z * (1./ 255.));
>
>  VNormalizeEq(dest_vec);   /* already good to about 1%, but we can do better */
>}
>
>extern BYTE_XYZ rad_samples[];
>
>void ChooseRay(RAY *NewRay, VECTOR Normal, RAY *Ray, VECTOR Raw_Normal, int WhichRay)
>{
>  VECTOR random_vec, up, n2, n3;
>  int i;
>  DBL /*n,*/ NRay_Direction;
>
>  Assign_Vector(NewRay->Direction, Normal);
>
>  if ( fabs(fabs(NewRay->Direction[Z])- 1.) < .1 ) {
>    /* too close to vertical for comfort, so use cross product with horizon */
>    up[X] = 0.; up[Y] = 1.; up[Z] = 0.;
>  }
>  else
>  {
>    up[X] = 0.; up[Y] = 0.; up[Z] = 1.;
>  }
>
>  VCross(n2, NewRay->Direction, up);  VNormalizeEq(n2);
>  VCross(n3, NewRay->Direction, n2);  VNormalizeEq(n3);
>
>  /*i = (int)(FRAND()*1600);*/
>  i = WhichRay;
>  WhichRay = (WhichRay + 1) % 1600;
>
>  VUnpack(random_vec, &rad_samples[i]);
>
>  if ( fabs(NewRay->Direction[Z] - 1.) < .001 )         /* pretty well straight Z, folks */
>  {
>    /* we are within 1/20 degree of pointing in the Z axis. */
>    /* use all vectors as is--they're precomputed this way */
>    Assign_Vector(NewRay->Direction, random_vec);
>  }
>  else
>  {
>    NewRay->Direction[X] = n2[X]*random_vec[X] + n3[X]*random_vec[Y] + NewRay->Direction[X]*random_vec[Z];
>    NewRay->Direction[Y] = n2[Y]*random_vec[X] + n3[Y]*random_vec[Y] + NewRay->Direction[Y]*random_vec[Z];
>    NewRay->Direction[Z] = n2[Z]*random_vec[X] + n3[Z]*random_vec[Y] + NewRay->Direction[Z]*random_vec[Z];
>  }
>
>  /* if our new ray goes through, flip it back across raw_normal */
>
>  VDot(NRay_Direction, NewRay->Direction, Raw_Normal);
>  if (NRay_Direction < 0.0)
>  {
>    /* subtract 2*(projection of NRay.Direction onto Raw_Normal)
>       from NRay.Direction */
>    DBL Proj;
>    Proj = NRay_Direction * -2;
>    VAddScaledEq(NewRay->Direction, Proj, Raw_Normal);
>  }
>
>  VNormalizeEq(NewRay->Direction);
>}
>

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Attachments on bug 19653: 8080 | 9374 | 9418 | 9445 | 9454