-/*\r
-Copyright (C) 1999-2007 id Software, Inc. and contributors.\r
-For a list of contributors, see the accompanying CONTRIBUTORS file.\r
-\r
-This file is part of GtkRadiant.\r
-\r
-GtkRadiant is free software; you can redistribute it and/or modify\r
-it under the terms of the GNU General Public License as published by\r
-the Free Software Foundation; either version 2 of the License, or\r
-(at your option) any later version.\r
-\r
-GtkRadiant is distributed in the hope that it will be useful,\r
-but WITHOUT ANY WARRANTY; without even the implied warranty of\r
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the\r
-GNU General Public License for more details.\r
-\r
-You should have received a copy of the GNU General Public License\r
-along with GtkRadiant; if not, write to the Free Software\r
-Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA\r
-*/\r
-\r
-\r
-\r
-#include "stdafx.h"\r
-#include <assert.h>\r
-#include "winding.h"\r
-\r
-#define BOGUS_RANGE (g_MaxWorldCoord+1)\r
-\r
-/*\r
-=============\r
-Plane_Equal\r
-=============\r
-*/\r
-#define NORMAL_EPSILON 0.0001\r
-#define DIST_EPSILON 0.02\r
-\r
-int Plane_Equal(plane_t *a, plane_t *b, int flip)\r
-{\r
- vec3_t normal;\r
- float dist;\r
-\r
- if (flip) {\r
- normal[0] = - b->normal[0];\r
- normal[1] = - b->normal[1];\r
- normal[2] = - b->normal[2];\r
- dist = - b->dist;\r
- }\r
- else {\r
- normal[0] = b->normal[0];\r
- normal[1] = b->normal[1];\r
- normal[2] = b->normal[2];\r
- dist = b->dist;\r
- }\r
- if (\r
- fabs(a->normal[0] - normal[0]) < NORMAL_EPSILON\r
- && fabs(a->normal[1] - normal[1]) < NORMAL_EPSILON\r
- && fabs(a->normal[2] - normal[2]) < NORMAL_EPSILON\r
- && fabs(a->dist - dist) < DIST_EPSILON )\r
- return true;\r
- return false;\r
-}\r
-\r
-/*\r
-============\r
-Plane_FromPoints\r
-============\r
-*/\r
-int Plane_FromPoints(vec3_t p1, vec3_t p2, vec3_t p3, plane_t *plane)\r
-{\r
- vec3_t v1, v2;\r
-\r
- VectorSubtract(p2, p1, v1);\r
- VectorSubtract(p3, p1, v2);\r
- //CrossProduct(v2, v1, plane->normal);\r
- CrossProduct(v1, v2, plane->normal);\r
- if (VectorNormalize(plane->normal, plane->normal) < 0.1) return false;\r
- plane->dist = DotProduct(p1, plane->normal);\r
- return true;\r
-}\r
-\r
-/*\r
-=================\r
-Point_Equal\r
-=================\r
-*/\r
-int Point_Equal(vec3_t p1, vec3_t p2, float epsilon)\r
-{\r
- int i;\r
-\r
- for (i = 0; i < 3; i++)\r
- {\r
- if (fabs(p1[i] - p2[i]) > epsilon) return false;\r
- }\r
- return true;\r
-}\r
-\r
-\r
-/*\r
-=================\r
-Winding_BaseForPlane\r
-=================\r
-*/\r
-//#define DBG_WNDG\r
-winding_t *Winding_BaseForPlane (plane_t *p)\r
-{\r
- int i, x;\r
- vec_t max, v;\r
- vec3_t org, vright, vup;\r
- winding_t *w;\r
- \r
- // find the major axis\r
-#ifdef DBG_WNDG\r
- Sys_Printf("Winding_BaseForPlane %p\n",p);\r
-#endif\r
-\r
- max = -BOGUS_RANGE;\r
- x = -1;\r
- for (i=0 ; i<3; i++)\r
- {\r
- v = fabs(p->normal[i]);\r
- if (v > max)\r
- {\r
- x = i;\r
- max = v;\r
- }\r
- }\r
- if (x==-1)\r
- Error ("Winding_BaseForPlane: no axis found");\r
- \r
- VectorCopy (vec3_origin, vup); \r
- switch (x)\r
- {\r
- case 0:\r
- case 1:\r
- vup[2] = 1;\r
- break; \r
- case 2:\r
- vup[0] = 1;\r
- break; \r
- }\r
-\r
-\r
- v = DotProduct (vup, p->normal);\r
- VectorMA (vup, -v, p->normal, vup);\r
- VectorNormalize (vup, vup);\r
- \r
- VectorScale (p->normal, p->dist, org);\r
- \r
- CrossProduct (vup, p->normal, vright);\r
- \r
- VectorScale (vup, BOGUS_RANGE, vup);\r
- VectorScale (vright, BOGUS_RANGE, vright);\r
-\r
- // project a really big axis aligned box onto the plane\r
- w = Winding_Alloc (4);\r
- \r
- VectorSubtract (org, vright, w->points[0]);\r
- VectorAdd (w->points[0], vup, w->points[0]);\r
- \r
- VectorAdd (org, vright, w->points[1]);\r
- VectorAdd (w->points[1], vup, w->points[1]);\r
- \r
- VectorAdd (org, vright, w->points[2]);\r
- VectorSubtract (w->points[2], vup, w->points[2]);\r
- \r
- VectorSubtract (org, vright, w->points[3]);\r
- VectorSubtract (w->points[3], vup, w->points[3]);\r
- \r
- w->numpoints = 4;\r
-\r
- return w; \r
-}\r
-\r
-// macro to compute winding size\r
-#define WINDING_SIZE(pt) (sizeof(int)*2+sizeof(float)*5*(pt))\r
-\r
-/*\r
-==================\r
-Winding_Alloc\r
-==================\r
-*/\r
-winding_t *Winding_Alloc (int points)\r
-{\r
- winding_t *w;\r
- int size;\r
- \r
- if (points > MAX_POINTS_ON_WINDING)\r
- Error ("Winding_Alloc: %i points", points);\r
- \r
-// size = (int)((winding_t *)0)->points[points];\r
- size = WINDING_SIZE(points);\r
- w = (winding_t*) malloc (size);\r
- memset (w, 0, size);\r
- w->maxpoints = points;\r
- \r
- return w;\r
-}\r
-\r
-void Winding_Free (winding_t *w)\r
-{\r
- free(w);\r
-}\r
-\r
-/*\r
-==================\r
-Winding_Clone\r
-==================\r
-*/\r
-winding_t *Winding_Clone(winding_t *w)\r
-{\r
- int size;\r
- winding_t *c;\r
- \r
-// size = (int)((winding_t *)0)->points[w->numpoints];\r
- size = WINDING_SIZE(w->numpoints);\r
- c = (winding_t*)qmalloc (size);\r
- memcpy (c, w, size);\r
- return c;\r
-}\r
-\r
-/*\r
-==================\r
-ReverseWinding\r
-==================\r
-*/\r
-winding_t *Winding_Reverse(winding_t *w)\r
-{\r
- int i;\r
- winding_t *c;\r
-\r
- c = Winding_Alloc(w->numpoints);\r
- for (i = 0; i < w->numpoints; i++)\r
- {\r
- VectorCopy (w->points[w->numpoints-1-i], c->points[i]);\r
- }\r
- c->numpoints = w->numpoints;\r
- return c;\r
-}\r
-\r
-/*\r
-==============\r
-Winding_RemovePoint\r
-==============\r
-*/\r
-void Winding_RemovePoint(winding_t *w, int point)\r
-{\r
- if (point < 0 || point >= w->numpoints)\r
- Error("Winding_RemovePoint: point out of range");\r
-\r
- if (point < w->numpoints-1)\r
- {\r
- memmove(&w->points[point], &w->points[point+1], (int)((winding_t *)0)->points[w->numpoints - point - 1]);\r
- }\r
- w->numpoints--;\r
-}\r
-\r
-/*\r
-=============\r
-Winding_InsertPoint\r
-=============\r
-*/\r
-winding_t *Winding_InsertPoint(winding_t *w, vec3_t point, int spot)\r
-{\r
- int i, j;\r
- winding_t *neww;\r
-\r
- if (spot > w->numpoints)\r
- {\r
- Error("Winding_InsertPoint: spot > w->numpoints");\r
- } //end if\r
- if (spot < 0)\r
- {\r
- Error("Winding_InsertPoint: spot < 0");\r
- } //end if\r
- neww = Winding_Alloc(w->numpoints + 1);\r
- neww->numpoints = w->numpoints + 1;\r
- for (i = 0, j = 0; i < neww->numpoints; i++)\r
- {\r
- if (i == spot)\r
- {\r
- VectorCopy(point, neww->points[i]);\r
- }\r
- else\r
- {\r
- VectorCopy(w->points[j], neww->points[i]);\r
- j++;\r
- }\r
- }\r
- return neww;\r
-}\r
-\r
-/*\r
-==============\r
-Winding_IsTiny\r
-==============\r
-*/\r
-#define EDGE_LENGTH 0.2\r
-\r
-int Winding_IsTiny (winding_t *w)\r
-{\r
- int i, j;\r
- vec_t len;\r
- vec3_t delta;\r
- int edges;\r
-\r
- edges = 0;\r
- for (i=0 ; i<w->numpoints ; i++)\r
- {\r
- j = i == w->numpoints - 1 ? 0 : i+1;\r
- VectorSubtract (w->points[j], w->points[i], delta);\r
- len = VectorLength (delta);\r
- if (len > EDGE_LENGTH)\r
- {\r
- if (++edges == 3)\r
- return false;\r
- }\r
- }\r
- return true;\r
-}\r
-\r
-/*\r
-==============\r
-Winding_IsHuge\r
-==============\r
-*/\r
-int Winding_IsHuge(winding_t *w)\r
-{\r
- int i, j;\r
-\r
- for (i=0 ; i<w->numpoints ; i++)\r
- {\r
- for (j=0 ; j<3 ; j++)\r
- if (w->points[i][j] < -BOGUS_RANGE+1 || w->points[i][j] > BOGUS_RANGE-1)\r
- return true;\r
- }\r
- return false;\r
-}\r
-\r
-/*\r
-=============\r
-Winding_PlanesConcave\r
-=============\r
-*/\r
-#define WCONVEX_EPSILON 0.2\r
-\r
-int Winding_PlanesConcave(winding_t *w1, winding_t *w2,\r
- vec3_t normal1, vec3_t normal2,\r
- float dist1, float dist2)\r
-{\r
- int i;\r
-\r
- if (!w1 || !w2) return false;\r
-\r
- // check if one of the points of winding 1 is at the back of the plane of winding 2\r
- for (i = 0; i < w1->numpoints; i++)\r
- {\r
- if (DotProduct(normal2, w1->points[i]) - dist2 > WCONVEX_EPSILON) return true;\r
- }\r
- // check if one of the points of winding 2 is at the back of the plane of winding 1\r
- for (i = 0; i < w2->numpoints; i++)\r
- {\r
- if (DotProduct(normal1, w2->points[i]) - dist1 > WCONVEX_EPSILON) return true;\r
- }\r
-\r
- return false;\r
-}\r
-\r
-/*\r
-==================\r
-Winding_Clip\r
-\r
-Clips the winding to the plane, returning the new winding on the positive side\r
-Frees the input winding.\r
-If keepon is true, an exactly on-plane winding will be saved, otherwise\r
-it will be clipped away.\r
-==================\r
-*/\r
-winding_t *Winding_Clip (winding_t *in, plane_t *split, qboolean keepon)\r
-{\r
- vec_t dists[MAX_POINTS_ON_WINDING];\r
- int sides[MAX_POINTS_ON_WINDING];\r
- int counts[3];\r
- vec_t dot;\r
- int i, j;\r
- vec_t *p1, *p2;\r
- vec3_t mid;\r
- winding_t *neww;\r
- int maxpts;\r
- \r
- counts[0] = counts[1] = counts[2] = 0;\r
-\r
- // determine sides for each point\r
- for (i=0 ; i<in->numpoints ; i++)\r
- {\r
- dot = DotProduct (in->points[i], split->normal);\r
- dot -= split->dist;\r
- dists[i] = dot;\r
- if (dot > ON_EPSILON)\r
- sides[i] = SIDE_FRONT;\r
- else if (dot < -ON_EPSILON)\r
- sides[i] = SIDE_BACK;\r
- else\r
- {\r
- sides[i] = SIDE_ON;\r
- }\r
- counts[sides[i]]++;\r
- }\r
- sides[i] = sides[0];\r
- dists[i] = dists[0];\r
- \r
- if (keepon && !counts[0] && !counts[1])\r
- return in;\r
- \r
- if (!counts[0])\r
- {\r
- Winding_Free (in);\r
- return NULL;\r
- }\r
- if (!counts[1])\r
- return in;\r
- \r
- maxpts = in->numpoints+4; // can't use counts[0]+2 because\r
- // of fp grouping errors\r
- neww = Winding_Alloc (maxpts);\r
- \r
- for (i=0 ; i<in->numpoints ; i++)\r
- {\r
- p1 = in->points[i];\r
- \r
- if (sides[i] == SIDE_ON)\r
- {\r
- VectorCopy (p1, neww->points[neww->numpoints]);\r
- neww->numpoints++;\r
- continue;\r
- }\r
- \r
- if (sides[i] == SIDE_FRONT)\r
- {\r
- VectorCopy (p1, neww->points[neww->numpoints]);\r
- neww->numpoints++;\r
- }\r
- \r
- if (sides[i+1] == SIDE_ON || sides[i+1] == sides[i])\r
- continue;\r
- \r
- // generate a split point\r
- p2 = in->points[(i+1)%in->numpoints];\r
- \r
- dot = dists[i] / (dists[i]-dists[i+1]);\r
- for (j=0 ; j<3 ; j++)\r
- { // avoid round off error when possible\r
- if (split->normal[j] == 1)\r
- mid[j] = split->dist;\r
- else if (split->normal[j] == -1)\r
- mid[j] = -split->dist;\r
- else\r
- mid[j] = p1[j] + dot*(p2[j]-p1[j]);\r
- }\r
- \r
- VectorCopy (mid, neww->points[neww->numpoints]);\r
- neww->numpoints++;\r
- }\r
- \r
- if (neww->numpoints > maxpts)\r
- Error ("Winding_Clip: points exceeded estimate");\r
- \r
- // free the original winding\r
- Winding_Free (in);\r
- \r
- return neww;\r
-}\r
-\r
-/*\r
-=============\r
-Winding_SplitEpsilon\r
-\r
- split the input winding with the plane\r
- the input winding stays untouched\r
-=============\r
-*/\r
-void Winding_SplitEpsilon (winding_t *in, vec3_t normal, double dist, \r
- vec_t epsilon, winding_t **front, winding_t **back)\r
-{\r
- vec_t dists[MAX_POINTS_ON_WINDING+4];\r
- int sides[MAX_POINTS_ON_WINDING+4];\r
- int counts[3];\r
- vec_t dot;\r
- int i, j;\r
- vec_t *p1, *p2;\r
- vec3_t mid;\r
- winding_t *f, *b;\r
- int maxpts;\r
- \r
- counts[0] = counts[1] = counts[2] = 0;\r
-\r
- // determine sides for each point\r
- for (i = 0; i < in->numpoints; i++)\r
- {\r
- dot = DotProduct (in->points[i], normal);\r
- dot -= dist;\r
- dists[i] = dot;\r
- if (dot > epsilon)\r
- sides[i] = SIDE_FRONT;\r
- else if (dot < -epsilon)\r
- sides[i] = SIDE_BACK;\r
- else\r
- {\r
- sides[i] = SIDE_ON;\r
- }\r
- counts[sides[i]]++;\r
- }\r
- sides[i] = sides[0];\r
- dists[i] = dists[0];\r
- \r
- *front = *back = NULL;\r
-\r
- if (!counts[0])\r
- {\r
- *back = Winding_Clone(in);\r
- return;\r
- }\r
- if (!counts[1])\r
- {\r
- *front = Winding_Clone(in);\r
- return;\r
- }\r
-\r
- maxpts = in->numpoints+4; // cant use counts[0]+2 because\r
- // of fp grouping errors\r
-\r
- *front = f = Winding_Alloc (maxpts);\r
- *back = b = Winding_Alloc (maxpts);\r
- \r
- for (i = 0; i < in->numpoints; i++)\r
- {\r
- p1 = in->points[i];\r
- \r
- if (sides[i] == SIDE_ON)\r
- {\r
- VectorCopy (p1, f->points[f->numpoints]);\r
- f->numpoints++;\r
- VectorCopy (p1, b->points[b->numpoints]);\r
- b->numpoints++;\r
- continue;\r
- }\r
- \r
- if (sides[i] == SIDE_FRONT)\r
- {\r
- VectorCopy (p1, f->points[f->numpoints]);\r
- f->numpoints++;\r
- }\r
- if (sides[i] == SIDE_BACK)\r
- {\r
- VectorCopy (p1, b->points[b->numpoints]);\r
- b->numpoints++;\r
- }\r
-\r
- if (sides[i+1] == SIDE_ON || sides[i+1] == sides[i])\r
- continue;\r
- \r
- // generate a split point\r
- p2 = in->points[(i+1)%in->numpoints];\r
- \r
- dot = dists[i] / (dists[i]-dists[i+1]);\r
- for (j = 0; j < 3; j++)\r
- {\r
- // avoid round off error when possible\r
- if (normal[j] == 1)\r
- mid[j] = dist;\r
- else if (normal[j] == -1)\r
- mid[j] = -dist;\r
- else\r
- mid[j] = p1[j] + dot*(p2[j]-p1[j]);\r
- }\r
- \r
- VectorCopy (mid, f->points[f->numpoints]);\r
- f->numpoints++;\r
- VectorCopy (mid, b->points[b->numpoints]);\r
- b->numpoints++;\r
- }\r
- \r
- if (f->numpoints > maxpts || b->numpoints > maxpts)\r
- Error ("Winding_Clip: points exceeded estimate");\r
- if (f->numpoints > MAX_POINTS_ON_WINDING || b->numpoints > MAX_POINTS_ON_WINDING)\r
- Error ("Winding_Clip: MAX_POINTS_ON_WINDING");\r
-}\r
-\r
-/*\r
-=============\r
-Winding_TryMerge\r
-\r
-If two windings share a common edge and the edges that meet at the\r
-common points are both inside the other polygons, merge them\r
-\r
-Returns NULL if the windings couldn't be merged, or the new winding.\r
-The originals will NOT be freed.\r
-\r
-if keep is true no points are ever removed\r
-=============\r
-*/\r
-#define CONTINUOUS_EPSILON 0.005\r
-\r
-winding_t *Winding_TryMerge(winding_t *f1, winding_t *f2, vec3_t planenormal, int keep)\r
-{\r
- vec_t *p1, *p2, *p3, *p4, *back;\r
- winding_t *newf;\r
- int i, j, k, l;\r
- vec3_t normal, delta;\r
- vec_t dot;\r
- qboolean keep1, keep2;\r
- \r
-\r
- //\r
- // find a common edge\r
- // \r
- p1 = p2 = NULL; // stop compiler warning\r
- j = 0; // \r
- \r
- for (i = 0; i < f1->numpoints; i++)\r
- {\r
- p1 = f1->points[i];\r
- p2 = f1->points[(i+1) % f1->numpoints];\r
- for (j = 0; j < f2->numpoints; j++)\r
- {\r
- p3 = f2->points[j];\r
- p4 = f2->points[(j+1) % f2->numpoints];\r
- for (k = 0; k < 3; k++)\r
- {\r
- if (fabs(p1[k] - p4[k]) > 0.1)//EQUAL_EPSILON) //ME\r
- break;\r
- if (fabs(p2[k] - p3[k]) > 0.1)//EQUAL_EPSILON) //ME\r
- break;\r
- } //end for\r
- if (k==3)\r
- break;\r
- } //end for\r
- if (j < f2->numpoints)\r
- break;\r
- } //end for\r
- \r
- if (i == f1->numpoints)\r
- return NULL; // no matching edges\r
-\r
- //\r
- // check slope of connected lines\r
- // if the slopes are colinear, the point can be removed\r
- //\r
- back = f1->points[(i+f1->numpoints-1)%f1->numpoints];\r
- VectorSubtract (p1, back, delta);\r
- CrossProduct (planenormal, delta, normal);\r
- VectorNormalize (normal, normal);\r
- \r
- back = f2->points[(j+2)%f2->numpoints];\r
- VectorSubtract (back, p1, delta);\r
- dot = DotProduct (delta, normal);\r
- if (dot > CONTINUOUS_EPSILON)\r
- return NULL; // not a convex polygon\r
- keep1 = (qboolean)(dot < -CONTINUOUS_EPSILON);\r
- \r
- back = f1->points[(i+2)%f1->numpoints];\r
- VectorSubtract (back, p2, delta);\r
- CrossProduct (planenormal, delta, normal);\r
- VectorNormalize (normal, normal);\r
-\r
- back = f2->points[(j+f2->numpoints-1)%f2->numpoints];\r
- VectorSubtract (back, p2, delta);\r
- dot = DotProduct (delta, normal);\r
- if (dot > CONTINUOUS_EPSILON)\r
- return NULL; // not a convex polygon\r
- keep2 = (qboolean)(dot < -CONTINUOUS_EPSILON);\r
-\r
- //\r
- // build the new polygon\r
- //\r
- newf = Winding_Alloc (f1->numpoints + f2->numpoints);\r
- \r
- // copy first polygon\r
- for (k=(i+1)%f1->numpoints ; k != i ; k=(k+1)%f1->numpoints)\r
- {\r
- if (!keep && k==(i+1)%f1->numpoints && !keep2)\r
- continue;\r
- \r
- VectorCopy (f1->points[k], newf->points[newf->numpoints]);\r
- newf->numpoints++;\r
- }\r
- \r
- // copy second polygon\r
- for (l= (j+1)%f2->numpoints ; l != j ; l=(l+1)%f2->numpoints)\r
- {\r
- if (!keep && l==(j+1)%f2->numpoints && !keep1)\r
- continue;\r
- VectorCopy (f2->points[l], newf->points[newf->numpoints]);\r
- newf->numpoints++;\r
- }\r
-\r
- return newf;\r
-}\r
-\r
-/*\r
-============\r
-Winding_Plane\r
-============\r
-*/\r
-void Winding_Plane (winding_t *w, vec3_t normal, double *dist)\r
-{\r
- vec3_t v1, v2;\r
- int i;\r
-\r
- //find two vectors each longer than 0.5 units\r
- for (i = 0; i < w->numpoints; i++)\r
- {\r
- VectorSubtract(w->points[(i+1) % w->numpoints], w->points[i], v1);\r
- VectorSubtract(w->points[(i+2) % w->numpoints], w->points[i], v2);\r
- if (VectorLength(v1) > 0.5 && VectorLength(v2) > 0.5) break;\r
- }\r
- CrossProduct(v2, v1, normal);\r
- VectorNormalize(normal, normal);\r
- *dist = DotProduct(w->points[0], normal);\r
-}\r
-\r
-/*\r
-=============\r
-Winding_Area\r
-=============\r
-*/\r
-float Winding_Area (winding_t *w)\r
-{\r
- int i;\r
- vec3_t d1, d2, cross;\r
- float total;\r
-\r
- total = 0;\r
- for (i=2 ; i<w->numpoints ; i++)\r
- {\r
- VectorSubtract (w->points[i-1], w->points[0], d1);\r
- VectorSubtract (w->points[i], w->points[0], d2);\r
- CrossProduct (d1, d2, cross);\r
- total += 0.5 * VectorLength ( cross );\r
- }\r
- return total;\r
-}\r
-\r
-/*\r
-=============\r
-Winding_Bounds\r
-=============\r
-*/\r
-void Winding_Bounds (winding_t *w, vec3_t mins, vec3_t maxs)\r
-{\r
- vec_t v;\r
- int i,j;\r
-\r
- mins[0] = mins[1] = mins[2] = 99999;\r
- maxs[0] = maxs[1] = maxs[2] = -99999;\r
-\r
- for (i=0 ; i<w->numpoints ; i++)\r
- {\r
- for (j=0 ; j<3 ; j++)\r
- {\r
- v = w->points[i][j];\r
- if (v < mins[j])\r
- mins[j] = v;\r
- if (v > maxs[j])\r
- maxs[j] = v;\r
- }\r
- }\r
-}\r
-\r
-\r
-/*\r
-=================\r
-Winding_PointInside\r
-=================\r
-*/\r
-int Winding_PointInside(winding_t *w, plane_t *plane, vec3_t point, float epsilon)\r
-{\r
- int i;\r
- vec3_t dir, normal, pointvec;\r
-\r
- for (i = 0; i < w->numpoints; i++)\r
- {\r
- VectorSubtract(w->points[(i+1) % w->numpoints], w->points[i], dir);\r
- VectorSubtract(point, w->points[i], pointvec);\r
- //\r
- CrossProduct(dir, plane->normal, normal);\r
- //\r
- if (DotProduct(pointvec, normal) < -epsilon) return false;\r
- }\r
- return true;\r
-}\r
-\r
-/*\r
-=================\r
-Winding_VectorIntersect\r
-=================\r
-*/\r
-int Winding_VectorIntersect(winding_t *w, plane_t *plane, vec3_t p1, vec3_t p2, float epsilon)\r
-{\r
- float front, back, frac;\r
- vec3_t mid;\r
-\r
- front = DotProduct(p1, plane->normal) - plane->dist;\r
- back = DotProduct(p2, plane->normal) - plane->dist;\r
- //if both points at the same side of the plane\r
- if (front < -epsilon && back < -epsilon) return false;\r
- if (front > epsilon && back > epsilon) return false;\r
- //get point of intersection with winding plane\r
- if (fabs(front-back) < 0.001)\r
- {\r
- VectorCopy(p2, mid);\r
- }\r
- else\r
- {\r
- frac = front/(front-back);\r
- mid[0] = p1[0] + (p2[0] - p1[0]) * frac;\r
- mid[1] = p1[1] + (p2[1] - p1[1]) * frac;\r
- mid[2] = p1[2] + (p2[2] - p1[2]) * frac;\r
- }\r
- return Winding_PointInside(w, plane, mid, epsilon);\r
-}\r
-\r
+/*
+ Copyright (C) 1999-2006 Id Software, Inc. and contributors.
+ For a list of contributors, see the accompanying CONTRIBUTORS file.
+
+ This file is part of GtkRadiant.
+
+ GtkRadiant 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.
+
+ GtkRadiant 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 GtkRadiant; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "winding.h"
+
+#include <algorithm>
+
+#include "math/line.h"
+
+
+inline double plane3_distance_to_point( const Plane3& plane, const DoubleVector3& point ){
+ return vector3_dot( point, plane.normal() ) - plane.dist();
+}
+
+inline double plane3_distance_to_point( const Plane3& plane, const Vector3& point ){
+ return vector3_dot( point, plane.normal() ) - plane.dist();
+}
+
+/// \brief Returns the point at which \p line intersects \p plane, or an undefined value if there is no intersection.
+inline DoubleVector3 line_intersect_plane( const DoubleLine& line, const Plane3& plane ){
+ return line.origin + vector3_scaled(
+ line.direction,
+ -plane3_distance_to_point( plane, line.origin )
+ / vector3_dot( line.direction, plane.normal() )
+ );
+}
+
+inline bool float_is_largest_absolute( double axis, double other ){
+ return fabs( axis ) > fabs( other );
+}
+
+/// \brief Returns the index of the component of \p v that has the largest absolute value.
+inline int vector3_largest_absolute_component_index( const DoubleVector3& v ){
+ return ( float_is_largest_absolute( v[1], v[0] ) )
+ ? ( float_is_largest_absolute( v[1], v[2] ) )
+ ? 1
+ : 2
+ : ( float_is_largest_absolute( v[0], v[2] ) )
+ ? 0
+ : 2;
+}
+
+/// \brief Returns the infinite line that is the intersection of \p plane and \p other.
+inline DoubleLine plane3_intersect_plane3( const Plane3& plane, const Plane3& other ){
+ DoubleLine line;
+ line.direction = vector3_cross( plane.normal(), other.normal() );
+ switch ( vector3_largest_absolute_component_index( line.direction ) )
+ {
+ case 0:
+ line.origin.x() = 0;
+ line.origin.y() = ( -other.dist() * plane.normal().z() - -plane.dist() * other.normal().z() ) / line.direction.x();
+ line.origin.z() = ( -plane.dist() * other.normal().y() - -other.dist() * plane.normal().y() ) / line.direction.x();
+ break;
+ case 1:
+ line.origin.x() = ( -plane.dist() * other.normal().z() - -other.dist() * plane.normal().z() ) / line.direction.y();
+ line.origin.y() = 0;
+ line.origin.z() = ( -other.dist() * plane.normal().x() - -plane.dist() * other.normal().x() ) / line.direction.y();
+ break;
+ case 2:
+ line.origin.x() = ( -other.dist() * plane.normal().y() - -plane.dist() * other.normal().y() ) / line.direction.z();
+ line.origin.y() = ( -plane.dist() * other.normal().x() - -other.dist() * plane.normal().x() ) / line.direction.z();
+ line.origin.z() = 0;
+ break;
+ default:
+ break;
+ }
+
+ return line;
+}
+
+
+/// \brief Keep the value of \p infinity as small as possible to improve precision in Winding_Clip.
+void Winding_createInfinite( FixedWinding& winding, const Plane3& plane, double infinity ){
+ double max = -infinity;
+ int x = -1;
+ for ( int i = 0 ; i < 3; i++ )
+ {
+ double d = fabs( plane.normal()[i] );
+ if ( d > max ) {
+ x = i;
+ max = d;
+ }
+ }
+ if ( x == -1 ) {
+ globalErrorStream() << "invalid plane\n";
+ return;
+ }
+
+ DoubleVector3 vup = g_vector3_identity;
+ switch ( x )
+ {
+ case 0:
+ case 1:
+ vup[2] = 1;
+ break;
+ case 2:
+ vup[0] = 1;
+ break;
+ }
+
+
+ vector3_add( vup, vector3_scaled( plane.normal(), -vector3_dot( vup, plane.normal() ) ) );
+ vector3_normalise( vup );
+
+ DoubleVector3 org = vector3_scaled( plane.normal(), plane.dist() );
+
+ DoubleVector3 vright = vector3_cross( vup, plane.normal() );
+
+ vector3_scale( vup, infinity );
+ vector3_scale( vright, infinity );
+
+ // project a really big axis aligned box onto the plane
+
+ DoubleLine r1, r2, r3, r4;
+ r1.origin = vector3_added( vector3_subtracted( org, vright ), vup );
+ r1.direction = vector3_normalised( vright );
+ winding.push_back( FixedWindingVertex( r1.origin, r1, c_brush_maxFaces ) );
+ r2.origin = vector3_added( vector3_added( org, vright ), vup );
+ r2.direction = vector3_normalised( vector3_negated( vup ) );
+ winding.push_back( FixedWindingVertex( r2.origin, r2, c_brush_maxFaces ) );
+ r3.origin = vector3_subtracted( vector3_added( org, vright ), vup );
+ r3.direction = vector3_normalised( vector3_negated( vright ) );
+ winding.push_back( FixedWindingVertex( r3.origin, r3, c_brush_maxFaces ) );
+ r4.origin = vector3_subtracted( vector3_subtracted( org, vright ), vup );
+ r4.direction = vector3_normalised( vup );
+ winding.push_back( FixedWindingVertex( r4.origin, r4, c_brush_maxFaces ) );
+}
+
+
+inline PlaneClassification Winding_ClassifyDistance( const double distance, const double epsilon ){
+ if ( distance > epsilon ) {
+ return ePlaneFront;
+ }
+ if ( distance < -epsilon ) {
+ return ePlaneBack;
+ }
+ return ePlaneOn;
+}
+
+/// \brief Returns true if
+/// !flipped && winding is completely BACK or ON
+/// or flipped && winding is completely FRONT or ON
+bool Winding_TestPlane( const Winding& winding, const Plane3& plane, bool flipped ){
+ const int test = ( flipped ) ? ePlaneBack : ePlaneFront;
+ for ( Winding::const_iterator i = winding.begin(); i != winding.end(); ++i )
+ {
+ if ( test == Winding_ClassifyDistance( plane3_distance_to_point( plane, ( *i ).vertex ), ON_EPSILON ) ) {
+ return false;
+ }
+ }
+ return true;
+}
+
+/// \brief Returns true if any point in \p w1 is in front of plane2, or any point in \p w2 is in front of plane1
+bool Winding_PlanesConcave( const Winding& w1, const Winding& w2, const Plane3& plane1, const Plane3& plane2 ){
+ return !Winding_TestPlane( w1, plane2, false ) || !Winding_TestPlane( w2, plane1, false );
+}
+
+brushsplit_t Winding_ClassifyPlane( const Winding& winding, const Plane3& plane ){
+ brushsplit_t split;
+ for ( Winding::const_iterator i = winding.begin(); i != winding.end(); ++i )
+ {
+ ++split.counts[Winding_ClassifyDistance( plane3_distance_to_point( plane, ( *i ).vertex ), ON_EPSILON )];
+ }
+ return split;
+}
+
+
+#define DEBUG_EPSILON ON_EPSILON
+const double DEBUG_EPSILON_SQUARED = DEBUG_EPSILON * DEBUG_EPSILON;
+
+#define WINDING_DEBUG 0
+
+/// \brief Clip \p winding which lies on \p plane by \p clipPlane, resulting in \p clipped.
+/// If \p winding is completely in front of the plane, \p clipped will be identical to \p winding.
+/// If \p winding is completely in back of the plane, \p clipped will be empty.
+/// If \p winding intersects the plane, the edge of \p clipped which lies on \p clipPlane will store the value of \p adjacent.
+void Winding_Clip( const FixedWinding& winding, const Plane3& plane, const Plane3& clipPlane, std::size_t adjacent, FixedWinding& clipped ){
+ PlaneClassification classification = Winding_ClassifyDistance( plane3_distance_to_point( clipPlane, winding.back().vertex ), ON_EPSILON );
+ PlaneClassification nextClassification;
+ // for each edge
+ for ( std::size_t next = 0, i = winding.size() - 1; next != winding.size(); i = next, ++next, classification = nextClassification )
+ {
+ nextClassification = Winding_ClassifyDistance( plane3_distance_to_point( clipPlane, winding[next].vertex ), ON_EPSILON );
+ const FixedWindingVertex& vertex = winding[i];
+
+ // if first vertex of edge is ON
+ if ( classification == ePlaneOn ) {
+ // append first vertex to output winding
+ if ( nextClassification == ePlaneBack ) {
+ // this edge lies on the clip plane
+ clipped.push_back( FixedWindingVertex( vertex.vertex, plane3_intersect_plane3( plane, clipPlane ), adjacent ) );
+ }
+ else
+ {
+ clipped.push_back( vertex );
+ }
+ continue;
+ }
+
+ // if first vertex of edge is FRONT
+ if ( classification == ePlaneFront ) {
+ // add first vertex to output winding
+ clipped.push_back( vertex );
+ }
+ // if second vertex of edge is ON
+ if ( nextClassification == ePlaneOn ) {
+ continue;
+ }
+ // else if second vertex of edge is same as first
+ else if ( nextClassification == classification ) {
+ continue;
+ }
+ // else if first vertex of edge is FRONT and there are only two edges
+ else if ( classification == ePlaneFront && winding.size() == 2 ) {
+ continue;
+ }
+ // else first vertex is FRONT and second is BACK or vice versa
+ else
+ {
+ // append intersection point of line and plane to output winding
+ DoubleVector3 mid( line_intersect_plane( vertex.edge, clipPlane ) );
+
+ if ( classification == ePlaneFront ) {
+ // this edge lies on the clip plane
+ clipped.push_back( FixedWindingVertex( mid, plane3_intersect_plane3( plane, clipPlane ), adjacent ) );
+ }
+ else
+ {
+ clipped.push_back( FixedWindingVertex( mid, vertex.edge, vertex.adjacent ) );
+ }
+ }
+ }
+}
+
+std::size_t Winding_FindAdjacent( const Winding& winding, std::size_t face ){
+ for ( std::size_t i = 0; i < winding.numpoints; ++i )
+ {
+ ASSERT_MESSAGE( winding[i].adjacent != c_brush_maxFaces, "edge connectivity data is invalid" );
+ if ( winding[i].adjacent == face ) {
+ return i;
+ }
+ }
+ return c_brush_maxFaces;
+}
+
+std::size_t Winding_Opposite( const Winding& winding, const std::size_t index, const std::size_t other ){
+ ASSERT_MESSAGE( index < winding.numpoints && other < winding.numpoints, "Winding_Opposite: index out of range" );
+
+ double dist_best = 0;
+ std::size_t index_best = c_brush_maxFaces;
+
+ Ray edge( ray_for_points( winding[index].vertex, winding[other].vertex ) );
+
+ for ( std::size_t i = 0; i < winding.numpoints; ++i )
+ {
+ if ( i == index || i == other ) {
+ continue;
+ }
+
+ double dist_squared = ray_squared_distance_to_point( edge, winding[i].vertex );
+
+ if ( dist_squared > dist_best ) {
+ dist_best = dist_squared;
+ index_best = i;
+ }
+ }
+ return index_best;
+}
+
+std::size_t Winding_Opposite( const Winding& winding, const std::size_t index ){
+ return Winding_Opposite( winding, index, Winding_next( winding, index ) );
+}
+
+/// \brief Calculate the \p centroid of the polygon defined by \p winding which lies on plane \p plane.
+void Winding_Centroid( const Winding& winding, const Plane3& plane, Vector3& centroid ){
+ double area2 = 0, x_sum = 0, y_sum = 0;
+ const ProjectionAxis axis = projectionaxis_for_normal( plane.normal() );
+ const indexremap_t remap = indexremap_for_projectionaxis( axis );
+ for ( std::size_t i = winding.numpoints - 1, j = 0; j < winding.numpoints; i = j, ++j )
+ {
+ const double ai = winding[i].vertex[remap.x] * winding[j].vertex[remap.y] - winding[j].vertex[remap.x] * winding[i].vertex[remap.y];
+ area2 += ai;
+ x_sum += ( winding[j].vertex[remap.x] + winding[i].vertex[remap.x] ) * ai;
+ y_sum += ( winding[j].vertex[remap.y] + winding[i].vertex[remap.y] ) * ai;
+ }
+
+ centroid[remap.x] = static_cast<float>( x_sum / ( 3 * area2 ) );
+ centroid[remap.y] = static_cast<float>( y_sum / ( 3 * area2 ) );
+ {
+ Ray ray( Vector3( 0, 0, 0 ), Vector3( 0, 0, 0 ) );
+ ray.origin[remap.x] = centroid[remap.x];
+ ray.origin[remap.y] = centroid[remap.y];
+ ray.direction[remap.z] = 1;
+ centroid[remap.z] = static_cast<float>( ray_distance_to_plane( ray, plane ) );
+ }
+}