contrib/gtkgensurf/face.cpp

   1 /*
   2 GenSurf plugin for GtkRadiant
   3 Copyright (C) 2001 David Hyde, Loki software and qeradiant.com
   4
   5 This library is free software; you can redistribute it and/or
   6 modify it under the terms of the GNU Lesser General Public
   7 License as published by the Free Software Foundation; either
   8 version 2.1 of the License, or (at your option) any later version.
   9
  10 This library is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13 Lesser General Public License for more details.
  14
  15 You should have received a copy of the GNU Lesser General Public
  16 License along with this library; if not, write to the Free Software
  17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18 */
  19
  20 #include <stdlib.h>
  21 #include <math.h>
  22 #include "gensurf.h"
  23
  24 #define MAX_FACES 128    // Maximum number of faces on a brush
  25 #define MAX_POINTS_ON_WINDING   64
  26 #define SIDE_FRONT              0
  27 #define SIDE_ON                 2
  28 #define SIDE_BACK               1
  29 #define SIDE_CROSS              -2
  30
  31 vec3 vec3_origin = {0,0,0};
  32
  33 void PlaneFromPoints (float *p0, float *p1, float *p2, PLANE *plane)
  34 {
  35         vec3 t1, t2;
  36         vec     length;
  37
  38         VectorSubtract (p0, p1, t1);
  39         VectorSubtract (p2, p1, t2);
  40         plane->normal[0] = t1[1]*t2[2] - t1[2]*t2[1];
  41         plane->normal[1] = t1[2]*t2[0] - t1[0]*t2[2];
  42         plane->normal[2] = t1[0]*t2[1] - t1[1]*t2[0];
  43
  44         length = (vec)(sqrt(plane->normal[0]*plane->normal[0] +
  45                                 plane->normal[1]*plane->normal[1] +
  46                                                 plane->normal[2]*plane->normal[2]  ));
  47         if (length == 0)
  48         {
  49                 VectorClear(plane->normal);
  50         }
  51         else
  52         {
  53                 plane->normal[0] /= length;
  54                 plane->normal[1] /= length;
  55                 plane->normal[2] /= length;
  56         }
  57         plane->dist = DotProduct (p0, plane->normal);
  58 }
  59
  60 void VectorMA (vec3 va, vec scale, vec3 vb, vec3 vc)
  61 {
  62         vc[0] = va[0] + scale*vb[0];
  63         vc[1] = va[1] + scale*vb[1];
  64         vc[2] = va[2] + scale*vb[2];
  65 }
  66
  67 void CrossProduct (vec3 v1, vec3 v2, vec3 cross)
  68 {
  69         cross[0] = v1[1]*v2[2] - v1[2]*v2[1];
  70         cross[1] = v1[2]*v2[0] - v1[0]*v2[2];
  71         cross[2] = v1[0]*v2[1] - v1[1]*v2[0];
  72 }
  73
  74 /*
  75 =============
  76 AllocWinding
  77 =============
  78 */
  79 MY_WINDING      *AllocWinding (int points)
  80 {
  81         MY_WINDING      *w;
  82         int                     s;
  83
  84         s = sizeof(vec)*3*points + sizeof(int);
  85         w = (MY_WINDING*)malloc (s);
  86         memset (w, 0, s);
  87         return w;
  88 }
  89
  90 vec VectorNormalize (vec3 in, vec3 out)
  91 {
  92         vec     length, ilength;
  93
  94         length = (vec)(sqrt (in[0]*in[0] + in[1]*in[1] + in[2]*in[2]));
  95         if (length == 0)
  96         {
  97                 VectorClear (out);
  98                 return 0;
  99         }
 100
 101         ilength = (vec)1.0/length;
 102         out[0] = in[0]*ilength;
 103         out[1] = in[1]*ilength;
 104         out[2] = in[2]*ilength;
 105
 106         return length;
 107 }
 108
 109 /*
 110 =================
 111 BaseWindingForPlane
 112 =================
 113 */
 114 MY_WINDING *BaseWindingForPlane (vec3 normal, vec dist)
 115 {
 116         int                i, x;
 117         vec        max, v;
 118         vec3       org, vright, vup;
 119         MY_WINDING *w;
 120
 121 // find the major axis
 122
 123         max = -BOGUS_RANGE;
 124         x = -1;
 125         for (i=0 ; i<3; i++)
 126         {
 127                 v = (vec)(fabs(normal[i]));
 128                 if (v > max)
 129                 {
 130                         x = i;
 131                         max = v;
 132                 }
 133         }
 134         if (x==-1) x = 2;
 135
 136         VectorCopy(vec3_origin,vup);
 137         switch (x)
 138         {
 139         case 0:
 140         case 1:
 141                 vup[2] = 1;
 142                 break;
 143         case 2:
 144                 vup[0] = 1;
 145                 break;
 146         }
 147
 148         v = DotProduct (vup, normal);
 149         VectorMA (vup, -v, normal, vup);
 150         VectorNormalize (vup, vup);
 151
 152         VectorScale (normal, dist, org);
 153
 154         CrossProduct (vup, normal, vright);
 155
 156         VectorScale (vup, 65536, vup);
 157         VectorScale (vright, 65536, vright);
 158
 159 // project a really big axis aligned box onto the plane
 160         w = AllocWinding (4);
 161
 162         VectorSubtract (org, vright, w->p[0]);
 163         VectorAdd (w->p[0], vup, w->p[0]);
 164
 165         VectorAdd (org, vright, w->p[1]);
 166         VectorAdd (w->p[1], vup, w->p[1]);
 167
 168         VectorAdd (org, vright, w->p[2]);
 169         VectorSubtract (w->p[2], vup, w->p[2]);
 170
 171         VectorSubtract (org, vright, w->p[3]);
 172         VectorSubtract (w->p[3], vup, w->p[3]);
 173
 174         w->numpoints = 4;
 175
 176         return w;
 177 }
 178
 179 void FreeWinding (MY_WINDING *w)
 180 {
 181         if (*(unsigned *)w == 0xdeaddead)
 182 //              Error ("FreeWinding: freed a freed winding");
 183                 return;
 184         *(unsigned *)w = 0xdeaddead;
 185
 186         free (w);
 187 }
 188
 189 /*
 190 =============
 191 ChopWindingInPlace
 192 =============
 193 */
 194 void ChopWindingInPlace (MY_WINDING **inout, vec3 normal, vec dist, vec epsilon)
 195 {
 196         MY_WINDING *in;
 197         vec        dists[MAX_POINTS_ON_WINDING+4];
 198         int        sides[MAX_POINTS_ON_WINDING+4];
 199         int        counts[3];
 200         static vec dot;         // VC 4.2 optimizer bug if not static
 201         int        i, j;
 202         vec        *p1, *p2;
 203         vec3       mid;
 204         MY_WINDING *f;
 205         int        maxpts;
 206
 207         in = *inout;
 208         counts[0] = counts[1] = counts[2] = 0;
 209
 210 // determine sides for each point
 211         for (i=0 ; i<in->numpoints ; i++)
 212         {
 213                 dot = DotProduct (in->p[i], normal);
 214                 dot -= dist;
 215                 dists[i] = dot;
 216                 if (dot > epsilon)
 217                         sides[i] = SIDE_FRONT;
 218                 else if (dot < -epsilon)
 219                         sides[i] = SIDE_BACK;
 220                 else
 221                 {
 222                         sides[i] = SIDE_ON;
 223                 }
 224                 counts[sides[i]]++;
 225         }
 226         sides[i] = sides[0];
 227         dists[i] = dists[0];
 228
 229         if (!counts[0])
 230         {
 231                 FreeWinding(in);
 232                 *inout = NULL;
 233                 return;
 234         }
 235         if (!counts[1])
 236                 return;         // inout stays the same
 237
 238         maxpts = in->numpoints+4;       // cant use counts[0]+2 because
 239                                                                 // of fp grouping errors
 240
 241         f = AllocWinding (maxpts);
 242
 243         for (i=0 ; i<in->numpoints ; i++)
 244         {
 245                 p1 = in->p[i];
 246
 247                 if (sides[i] == SIDE_ON)
 248                 {
 249                         VectorCopy (p1, f->p[f->numpoints]);
 250                         f->numpoints++;
 251                         continue;
 252                 }
 253
 254                 if (sides[i] == SIDE_FRONT)
 255                 {
 256                         VectorCopy (p1, f->p[f->numpoints]);
 257                         f->numpoints++;
 258                 }
 259
 260                 if (sides[i+1] == SIDE_ON || sides[i+1] == sides[i])
 261                         continue;
 262
 263         // generate a split point
 264                 p2 = in->p[(i+1)%in->numpoints];
 265
 266                 dot = dists[i] / (dists[i]-dists[i+1]);
 267                 for (j=0 ; j<3 ; j++)
 268                 {       // avoid round off error when possible
 269                         if (normal[j] == 1)
 270                                 mid[j] = dist;
 271                         else if (normal[j] == -1)
 272                                 mid[j] = -dist;
 273                         else
 274                                 mid[j] = p1[j] + dot*(p2[j]-p1[j]);
 275                 }
 276
 277                 VectorCopy (mid, f->p[f->numpoints]);
 278                 f->numpoints++;
 279         }
 280
 281 //      if (f->numpoints > maxpts)
 282 //              Error ("ClipWinding: points exceeded estimate");
 283 //      if (f->numpoints > MAX_POINTS_ON_WINDING)
 284 //              Error ("ClipWinding: MAX_POINTS_ON_WINDING");
 285
 286         FreeWinding(in);
 287         *inout = f;
 288 }
 289
 290 void UseFaceBounds()
 291 {
 292         LPVOID       vp;
 293         float        Dot, BestDot;
 294         float            planepts[3][3];
 295         int          BestFace;
 296         int          i, j;
 297         int          NumFaces;
 298         vec3         SurfNormal;
 299         vec3         vmin,vmax;
 300         _QERFaceData *QERFaceData;
 301         PLANE        plane[MAX_FACES*2];
 302         PLANE        pface;
 303         MY_WINDING   *w;
 304
 305         switch(Plane)
 306         {
 307         case PLANE_XY1:
 308                 SurfNormal[0] = 0.0;
 309                 SurfNormal[1] = 0.0;
 310                 SurfNormal[2] =-1.0;
 311                 break;
 312         case PLANE_XZ0:
 313                 SurfNormal[0] = 0.0;
 314                 SurfNormal[1] = 1.0;
 315                 SurfNormal[2] = 0.0;
 316                 break;
 317         case PLANE_XZ1:
 318                 SurfNormal[0] = 0.0;
 319                 SurfNormal[1] =-1.0;
 320                 SurfNormal[2] = 0.0;
 321                 break;
 322         case PLANE_YZ0:
 323                 SurfNormal[0] = 1.0;
 324                 SurfNormal[1] = 0.0;
 325                 SurfNormal[2] = 0.0;
 326                 break;
 327         case PLANE_YZ1:
 328                 SurfNormal[0] =-1.0;
 329                 SurfNormal[1] = 0.0;
 330                 SurfNormal[2] = 0.0;
 331                 break;
 332         default:
 333                 SurfNormal[0] = 0.0;
 334                 SurfNormal[1] = 0.0;
 335                 SurfNormal[2] = 1.0;
 336         }
 337
 338         i  = g_FuncTable.m_pfnAllocateSelectedBrushHandles();
 339         vp = g_FuncTable.m_pfnGetSelectedBrushHandle(0);
 340         NumFaces = g_FuncTable.m_pfnGetFaceCount(vp);
 341
 342         BestFace = -1;
 343         BestDot  = 0.0;
 344
 345         for(i=0; i<NumFaces; i++)
 346         {
 347                 QERFaceData = g_FuncTable.m_pfnGetFaceData(vp,i);
 348                 planepts[0][0] = QERFaceData->m_v1[0];
 349                 planepts[0][1] = QERFaceData->m_v1[1];
 350                 planepts[0][2] = QERFaceData->m_v1[2];
 351                 planepts[1][0] = QERFaceData->m_v2[0];
 352                 planepts[1][1] = QERFaceData->m_v2[1];
 353                 planepts[1][2] = QERFaceData->m_v2[2];
 354                 planepts[2][0] = QERFaceData->m_v3[0];
 355                 planepts[2][1] = QERFaceData->m_v3[1];
 356                 planepts[2][2] = QERFaceData->m_v3[2];
 357
 358                 PlaneFromPoints (planepts[0], planepts[1], planepts[2], &plane[2*i]);
 359                 VectorSubtract (vec3_origin, plane[2*i].normal, plane[2*i+1].normal);
 360                 plane[2*i+1].dist = -plane[2*i].dist;
 361
 362                 Dot = DotProduct(plane[2*i].normal,SurfNormal);
 363                 if(Dot > BestDot)
 364                 {
 365                         BestDot  = Dot;
 366                         BestFace = i;
 367                         if(strlen(QERFaceData->m_TextureName))
 368                                 strcpy(Texture[Game][0],QERFaceData->m_TextureName);
 369                 }
 370         }
 371         for(i=0; i<NumFaces; i++)
 372         {
 373                 if(i==BestFace) continue;
 374                 QERFaceData = g_FuncTable.m_pfnGetFaceData(vp,i);
 375                 if(strlen(QERFaceData->m_TextureName))
 376                 {
 377                         if(strcmp(Texture[Game][0],QERFaceData->m_TextureName))
 378                                 strcpy(Texture[Game][1],QERFaceData->m_TextureName);
 379                 }
 380         }
 381
 382
 383         g_FuncTable.m_pfnReleaseSelectedBrushHandles();
 384
 385         w = BaseWindingForPlane (plane[BestFace*2].normal, plane[BestFace*2].dist);
 386
 387         for (i=0 ; i<NumFaces && w; i++)
 388         {
 389                 if (BestFace == i)
 390                         continue;
 391                 ChopWindingInPlace (&w, plane[i*2+1].normal, plane[i*2+1].dist, 0);
 392         }
 393         if(!w) return;
 394
 395         // Get bounding box for this face
 396         vmin[0] = vmax[0] = w->p[0][0];
 397         vmin[1] = vmax[1] = w->p[0][1];
 398         vmin[2] = vmax[2] = w->p[0][2];
 399         for(j=1; j<w->numpoints; j++)
 400         {
 401                 vmin[0] = min(vmin[0],w->p[j][0]);
 402                 vmin[1] = min(vmin[1],w->p[j][1]);
 403                 vmin[2] = min(vmin[2],w->p[j][2]);
 404                 vmax[0] = max(vmax[0],w->p[j][0]);
 405                 vmax[1] = max(vmax[1],w->p[j][1]);
 406                 vmax[2] = max(vmax[2],w->p[j][2]);
 407         }
 408
 409         FreeWinding(w);
 410
 411         VectorCopy(plane[BestFace*2].normal,pface.normal);
 412         pface.dist = plane[BestFace*2].dist;
 413         switch(Plane)
 414         {
 415         case PLANE_XZ0:
 416         case PLANE_XZ1:
 417                 if(pface.normal[1] == 0.) return;
 418                 Hll = vmin[0];
 419                 Hur = vmax[0];
 420                 Vll = vmin[2];
 421                 Vur = vmax[2];
 422                 Z00 = (pface.dist - pface.normal[0]*Hll - pface.normal[2]*Vll)/pface.normal[1];
 423                 Z01 = (pface.dist - pface.normal[0]*Hll - pface.normal[2]*Vur)/pface.normal[1];
 424                 Z10 = (pface.dist - pface.normal[0]*Hur - pface.normal[2]*Vll)/pface.normal[1];
 425                 Z11 = (pface.dist - pface.normal[0]*Hur - pface.normal[2]*Vur)/pface.normal[1];
 426                 break;
 427         case PLANE_YZ0:
 428         case PLANE_YZ1:
 429                 if(pface.normal[0] == 0.) return;
 430                 Hll = vmin[1];
 431                 Hur = vmax[1];
 432                 Vll = vmin[2];
 433                 Vur = vmax[2];
 434                 Z00 = (pface.dist - pface.normal[1]*Hll - pface.normal[2]*Vll)/pface.normal[0];
 435                 Z01 = (pface.dist - pface.normal[1]*Hll - pface.normal[2]*Vur)/pface.normal[0];
 436                 Z10 = (pface.dist - pface.normal[1]*Hur - pface.normal[2]*Vll)/pface.normal[0];
 437                 Z11 = (pface.dist - pface.normal[1]*Hur - pface.normal[2]*Vur)/pface.normal[0];
 438                 break;
 439         default:
 440                 if(pface.normal[2] == 0.) return;
 441                 Hll = vmin[0];
 442                 Hur = vmax[0];
 443                 Vll = vmin[1];
 444                 Vur = vmax[1];
 445                 Z00 = (pface.dist - pface.normal[0]*Hll - pface.normal[1]*Vll)/pface.normal[2];
 446                 Z01 = (pface.dist - pface.normal[0]*Hll - pface.normal[1]*Vur)/pface.normal[2];
 447                 Z10 = (pface.dist - pface.normal[0]*Hur - pface.normal[1]*Vll)/pface.normal[2];
 448                 Z11 = (pface.dist - pface.normal[0]*Hur - pface.normal[1]*Vur)/pface.normal[2];
 449         }
 450 }