]> de.git.xonotic.org Git - xonotic/netradiant.git/blobdiff - tools/quake2/extra/common/polylib.c
Q2Tools source - didn't import this in initially
[xonotic/netradiant.git] / tools / quake2 / extra / common / polylib.c
diff --git a/tools/quake2/extra/common/polylib.c b/tools/quake2/extra/common/polylib.c
new file mode 100644 (file)
index 0000000..c190ebd
--- /dev/null
@@ -0,0 +1,642 @@
+/*
+===========================================================================
+Copyright (C) 1997-2006 Id Software, Inc.
+
+This file is part of Quake 2 Tools source code.
+
+Quake 2 Tools source code is free software; you can redistribute it
+and/or modify it under the terms of the GNU General Public License as
+published by the Free Software Foundation; either version 2 of the License,
+or (at your option) any later version.
+
+Quake 2 Tools source code is distributed in the hope that it will be
+useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with Quake 2 Tools source code; if not, write to the Free Software
+Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+===========================================================================
+*/
+
+#include "cmdlib.h"
+#include "mathlib.h"
+#include "polylib.h"
+
+
+extern int numthreads;
+
+// counters are only bumped when running single threaded,
+// because they are an awefull coherence problem
+int    c_active_windings;
+int    c_peak_windings;
+int    c_winding_allocs;
+int    c_winding_points;
+
+#define        BOGUS_RANGE     8192
+
+void pw(winding_t *w)
+{
+       int             i;
+       for (i=0 ; i<w->numpoints ; i++)
+               printf ("(%5.1f, %5.1f, %5.1f)\n",w->p[i][0], w->p[i][1],w->p[i][2]);
+}
+
+
+/*
+=============
+AllocWinding
+=============
+*/
+winding_t      *AllocWinding (int points)
+{
+       winding_t       *w;
+       int                     s;
+
+       if (numthreads == 1)
+       {
+               c_winding_allocs++;
+               c_winding_points += points;
+               c_active_windings++;
+               if (c_active_windings > c_peak_windings)
+                       c_peak_windings = c_active_windings;
+       }
+       s = sizeof(vec_t)*3*points + sizeof(int);
+       w = malloc (s);
+       memset (w, 0, s);
+       return w;
+}
+
+void FreeWinding (winding_t *w)
+{
+       if (*(unsigned *)w == 0xdeaddead)
+               Error ("FreeWinding: freed a freed winding");
+       *(unsigned *)w = 0xdeaddead;
+
+       if (numthreads == 1)
+               c_active_windings--;
+       free (w);
+}
+
+/*
+============
+RemoveColinearPoints
+============
+*/
+int    c_removed;
+
+void   RemoveColinearPoints (winding_t *w)
+{
+       int             i, j, k;
+       vec3_t  v1, v2;
+       int             nump;
+       vec3_t  p[MAX_POINTS_ON_WINDING];
+
+       nump = 0;
+       for (i=0 ; i<w->numpoints ; i++)
+       {
+               j = (i+1)%w->numpoints;
+               k = (i+w->numpoints-1)%w->numpoints;
+               VectorSubtract (w->p[j], w->p[i], v1);
+               VectorSubtract (w->p[i], w->p[k], v2);
+               VectorNormalize(v1,v1);
+               VectorNormalize(v2,v2);
+               if (DotProduct(v1, v2) < 0.999)
+               {
+                       VectorCopy (w->p[i], p[nump]);
+                       nump++;
+               }
+       }
+
+       if (nump == w->numpoints)
+               return;
+
+       if (numthreads == 1)
+               c_removed += w->numpoints - nump;
+       w->numpoints = nump;
+       memcpy (w->p, p, nump*sizeof(p[0]));
+}
+
+/*
+============
+WindingPlane
+============
+*/
+void WindingPlane (winding_t *w, vec3_t normal, vec_t *dist)
+{
+       vec3_t  v1, v2;
+
+       VectorSubtract (w->p[1], w->p[0], v1);
+       VectorSubtract (w->p[2], w->p[0], v2);
+       CrossProduct (v2, v1, normal);
+       VectorNormalize (normal, normal);
+       *dist = DotProduct (w->p[0], normal);
+
+}
+
+/*
+=============
+WindingArea
+=============
+*/
+vec_t  WindingArea (winding_t *w)
+{
+       int             i;
+       vec3_t  d1, d2, cross;
+       vec_t   total;
+
+       total = 0;
+       for (i=2 ; i<w->numpoints ; i++)
+       {
+               VectorSubtract (w->p[i-1], w->p[0], d1);
+               VectorSubtract (w->p[i], w->p[0], d2);
+               CrossProduct (d1, d2, cross);
+               total += 0.5 * VectorLength ( cross );
+       }
+       return total;
+}
+
+void   WindingBounds (winding_t *w, vec3_t mins, vec3_t maxs)
+{
+       vec_t   v;
+       int             i,j;
+
+       mins[0] = mins[1] = mins[2] = 99999;
+       maxs[0] = maxs[1] = maxs[2] = -99999;
+
+       for (i=0 ; i<w->numpoints ; i++)
+       {
+               for (j=0 ; j<3 ; j++)
+               {
+                       v = w->p[i][j];
+                       if (v < mins[j])
+                               mins[j] = v;
+                       if (v > maxs[j])
+                               maxs[j] = v;
+               }
+       }
+}
+
+/*
+=============
+WindingCenter
+=============
+*/
+void   WindingCenter (winding_t *w, vec3_t center)
+{
+       int             i;
+       float   scale;
+
+       VectorCopy (vec3_origin, center);
+       for (i=0 ; i<w->numpoints ; i++)
+               VectorAdd (w->p[i], center, center);
+
+       scale = 1.0/w->numpoints;
+       VectorScale (center, scale, center);
+}
+
+/*
+=================
+BaseWindingForPlane
+=================
+*/
+winding_t *BaseWindingForPlane (vec3_t normal, vec_t dist)
+{
+       int             i, x;
+       vec_t   max, v;
+       vec3_t  org, vright, vup;
+       winding_t       *w;
+
+// find the major axis
+
+       max = -BOGUS_RANGE;
+       x = -1;
+       for (i=0 ; i<3; i++)
+       {
+               v = fabs(normal[i]);
+               if (v > max)
+               {
+                       x = i;
+                       max = v;
+               }
+       }
+       if (x==-1)
+               Error ("BaseWindingForPlane: no axis found");
+
+       VectorCopy (vec3_origin, vup);
+       switch (x)
+       {
+       case 0:
+       case 1:
+               vup[2] = 1;
+               break;
+       case 2:
+               vup[0] = 1;
+               break;
+       }
+
+       v = DotProduct (vup, normal);
+       VectorMA (vup, -v, normal, vup);
+       VectorNormalize (vup, vup);
+
+       VectorScale (normal, dist, org);
+
+       CrossProduct (vup, normal, vright);
+
+       VectorScale (vup, 8192, vup);
+       VectorScale (vright, 8192, vright);
+
+// project a really big        axis aligned box onto the plane
+       w = AllocWinding (4);
+
+       VectorSubtract (org, vright, w->p[0]);
+       VectorAdd (w->p[0], vup, w->p[0]);
+
+       VectorAdd (org, vright, w->p[1]);
+       VectorAdd (w->p[1], vup, w->p[1]);
+
+       VectorAdd (org, vright, w->p[2]);
+       VectorSubtract (w->p[2], vup, w->p[2]);
+
+       VectorSubtract (org, vright, w->p[3]);
+       VectorSubtract (w->p[3], vup, w->p[3]);
+
+       w->numpoints = 4;
+
+       return w;
+}
+
+/*
+==================
+CopyWinding
+==================
+*/
+winding_t      *CopyWinding (winding_t *w)
+{
+       int                     size;
+       winding_t       *c;
+
+       c = AllocWinding (w->numpoints);
+       size = (int)((winding_t *)0)->p[w->numpoints];
+       memcpy (c, w, size);
+       return c;
+}
+
+/*
+==================
+ReverseWinding
+==================
+*/
+winding_t      *ReverseWinding (winding_t *w)
+{
+       int                     i;
+       winding_t       *c;
+
+       c = AllocWinding (w->numpoints);
+       for (i=0 ; i<w->numpoints ; i++)
+       {
+               VectorCopy (w->p[w->numpoints-1-i], c->p[i]);
+       }
+       c->numpoints = w->numpoints;
+       return c;
+}
+
+
+/*
+=============
+ClipWindingEpsilon
+=============
+*/
+void   ClipWindingEpsilon (winding_t *in, vec3_t normal, vec_t dist,
+                               vec_t epsilon, winding_t **front, winding_t **back)
+{
+       vec_t   dists[MAX_POINTS_ON_WINDING+4];
+       int             sides[MAX_POINTS_ON_WINDING+4];
+       int             counts[3];
+       static  vec_t   dot;            // VC 4.2 optimizer bug if not static
+       int             i, j;
+       vec_t   *p1, *p2;
+       vec3_t  mid;
+       winding_t       *f, *b;
+       int             maxpts;
+
+       counts[0] = counts[1] = counts[2] = 0;
+
+// determine sides for each point
+       for (i=0 ; i<in->numpoints ; i++)
+       {
+               dot = DotProduct (in->p[i], normal);
+               dot -= dist;
+               dists[i] = dot;
+               if (dot > epsilon)
+                       sides[i] = SIDE_FRONT;
+               else if (dot < -epsilon)
+                       sides[i] = SIDE_BACK;
+               else
+               {
+                       sides[i] = SIDE_ON;
+               }
+               counts[sides[i]]++;
+       }
+       sides[i] = sides[0];
+       dists[i] = dists[0];
+
+       *front = *back = NULL;
+
+       if (!counts[0])
+       {
+               *back = CopyWinding (in);
+               return;
+       }
+       if (!counts[1])
+       {
+               *front = CopyWinding (in);
+               return;
+       }
+
+       maxpts = in->numpoints+4;       // cant use counts[0]+2 because
+                                                               // of fp grouping errors
+
+       *front = f = AllocWinding (maxpts);
+       *back = b = AllocWinding (maxpts);
+
+       for (i=0 ; i<in->numpoints ; i++)
+       {
+               p1 = in->p[i];
+
+               if (sides[i] == SIDE_ON)
+               {
+                       VectorCopy (p1, f->p[f->numpoints]);
+                       f->numpoints++;
+                       VectorCopy (p1, b->p[b->numpoints]);
+                       b->numpoints++;
+                       continue;
+               }
+
+               if (sides[i] == SIDE_FRONT)
+               {
+                       VectorCopy (p1, f->p[f->numpoints]);
+                       f->numpoints++;
+               }
+               if (sides[i] == SIDE_BACK)
+               {
+                       VectorCopy (p1, b->p[b->numpoints]);
+                       b->numpoints++;
+               }
+
+               if (sides[i+1] == SIDE_ON || sides[i+1] == sides[i])
+                       continue;
+
+       // generate a split point
+               p2 = in->p[(i+1)%in->numpoints];
+
+               dot = dists[i] / (dists[i]-dists[i+1]);
+               for (j=0 ; j<3 ; j++)
+               {       // avoid round off error when possible
+                       if (normal[j] == 1)
+                               mid[j] = dist;
+                       else if (normal[j] == -1)
+                               mid[j] = -dist;
+                       else
+                               mid[j] = p1[j] + dot*(p2[j]-p1[j]);
+               }
+
+               VectorCopy (mid, f->p[f->numpoints]);
+               f->numpoints++;
+               VectorCopy (mid, b->p[b->numpoints]);
+               b->numpoints++;
+       }
+
+       if (f->numpoints > maxpts || b->numpoints > maxpts)
+               Error ("ClipWinding: points exceeded estimate");
+       if (f->numpoints > MAX_POINTS_ON_WINDING || b->numpoints > MAX_POINTS_ON_WINDING)
+               Error ("ClipWinding: MAX_POINTS_ON_WINDING");
+}
+
+
+/*
+=============
+ChopWindingInPlace
+=============
+*/
+void ChopWindingInPlace (winding_t **inout, vec3_t normal, vec_t dist, vec_t epsilon)
+{
+       winding_t       *in;
+       vec_t   dists[MAX_POINTS_ON_WINDING+4];
+       int             sides[MAX_POINTS_ON_WINDING+4];
+       int             counts[3];
+       static  vec_t   dot;            // VC 4.2 optimizer bug if not static
+       int             i, j;
+       vec_t   *p1, *p2;
+       vec3_t  mid;
+       winding_t       *f;
+       int             maxpts;
+
+       in = *inout;
+       counts[0] = counts[1] = counts[2] = 0;
+
+// determine sides for each point
+       for (i=0 ; i<in->numpoints ; i++)
+       {
+               dot = DotProduct (in->p[i], normal);
+               dot -= dist;
+               dists[i] = dot;
+               if (dot > epsilon)
+                       sides[i] = SIDE_FRONT;
+               else if (dot < -epsilon)
+                       sides[i] = SIDE_BACK;
+               else
+               {
+                       sides[i] = SIDE_ON;
+               }
+               counts[sides[i]]++;
+       }
+       sides[i] = sides[0];
+       dists[i] = dists[0];
+
+       if (!counts[0])
+       {
+               FreeWinding (in);
+               *inout = NULL;
+               return;
+       }
+       if (!counts[1])
+               return;         // inout stays the same
+
+       maxpts = in->numpoints+4;       // cant use counts[0]+2 because
+                                                               // of fp grouping errors
+
+       f = AllocWinding (maxpts);
+
+       for (i=0 ; i<in->numpoints ; i++)
+       {
+               p1 = in->p[i];
+
+               if (sides[i] == SIDE_ON)
+               {
+                       VectorCopy (p1, f->p[f->numpoints]);
+                       f->numpoints++;
+                       continue;
+               }
+
+               if (sides[i] == SIDE_FRONT)
+               {
+                       VectorCopy (p1, f->p[f->numpoints]);
+                       f->numpoints++;
+               }
+
+               if (sides[i+1] == SIDE_ON || sides[i+1] == sides[i])
+                       continue;
+
+       // generate a split point
+               p2 = in->p[(i+1)%in->numpoints];
+
+               dot = dists[i] / (dists[i]-dists[i+1]);
+               for (j=0 ; j<3 ; j++)
+               {       // avoid round off error when possible
+                       if (normal[j] == 1)
+                               mid[j] = dist;
+                       else if (normal[j] == -1)
+                               mid[j] = -dist;
+                       else
+                               mid[j] = p1[j] + dot*(p2[j]-p1[j]);
+               }
+
+               VectorCopy (mid, f->p[f->numpoints]);
+               f->numpoints++;
+       }
+
+       if (f->numpoints > maxpts)
+               Error ("ClipWinding: points exceeded estimate");
+       if (f->numpoints > MAX_POINTS_ON_WINDING)
+               Error ("ClipWinding: MAX_POINTS_ON_WINDING");
+
+       FreeWinding (in);
+       *inout = f;
+}
+
+
+/*
+=================
+ChopWinding
+
+Returns the fragment of in that is on the front side
+of the cliping plane.  The original is freed.
+=================
+*/
+winding_t      *ChopWinding (winding_t *in, vec3_t normal, vec_t dist)
+{
+       winding_t       *f, *b;
+
+       ClipWindingEpsilon (in, normal, dist, ON_EPSILON, &f, &b);
+       FreeWinding (in);
+       if (b)
+               FreeWinding (b);
+       return f;
+}
+
+
+/*
+=================
+CheckWinding
+
+=================
+*/
+void CheckWinding (winding_t *w)
+{
+       int             i, j;
+       vec_t   *p1, *p2;
+       vec_t   d, edgedist;
+       vec3_t  dir, edgenormal, facenormal;
+       vec_t   area;
+       vec_t   facedist;
+
+       if (w->numpoints < 3)
+               Error ("CheckWinding: %i points",w->numpoints);
+
+       area = WindingArea(w);
+       if (area < 1)
+               Error ("CheckWinding: %f area", area);
+
+       WindingPlane (w, facenormal, &facedist);
+
+       for (i=0 ; i<w->numpoints ; i++)
+       {
+               p1 = w->p[i];
+
+               for (j=0 ; j<3 ; j++)
+                       if (p1[j] > BOGUS_RANGE || p1[j] < -BOGUS_RANGE)
+                               Error ("CheckFace: BUGUS_RANGE: %f",p1[j]);
+
+               j = i+1 == w->numpoints ? 0 : i+1;
+
+       // check the point is on the face plane
+               d = DotProduct (p1, facenormal) - facedist;
+               if (d < -ON_EPSILON || d > ON_EPSILON)
+                       Error ("CheckWinding: point off plane");
+
+       // check the edge isnt degenerate
+               p2 = w->p[j];
+               VectorSubtract (p2, p1, dir);
+
+               if (VectorLength (dir) < ON_EPSILON)
+                       Error ("CheckWinding: degenerate edge");
+
+               CrossProduct (facenormal, dir, edgenormal);
+               VectorNormalize (edgenormal, edgenormal);
+               edgedist = DotProduct (p1, edgenormal);
+               edgedist += ON_EPSILON;
+
+       // all other points must be on front side
+               for (j=0 ; j<w->numpoints ; j++)
+               {
+                       if (j == i)
+                               continue;
+                       d = DotProduct (w->p[j], edgenormal);
+                       if (d > edgedist)
+                               Error ("CheckWinding: non-convex");
+               }
+       }
+}
+
+
+/*
+============
+WindingOnPlaneSide
+============
+*/
+int            WindingOnPlaneSide (winding_t *w, vec3_t normal, vec_t dist)
+{
+       qboolean        front, back;
+       int                     i;
+       vec_t           d;
+
+       front = false;
+       back = false;
+       for (i=0 ; i<w->numpoints ; i++)
+       {
+               d = DotProduct (w->p[i], normal) - dist;
+               if (d < -ON_EPSILON)
+               {
+                       if (front)
+                               return SIDE_CROSS;
+                       back = true;
+                       continue;
+               }
+               if (d > ON_EPSILON)
+               {
+                       if (back)
+                               return SIDE_CROSS;
+                       front = true;
+                       continue;
+               }
+       }
+
+       if (back)
+               return SIDE_BACK;
+       if (front)
+               return SIDE_FRONT;
+       return SIDE_ON;
+}
+