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Diffstat (limited to 'src/glu/sgi/libtess/normal.c')
| -rw-r--r-- | src/glu/sgi/libtess/normal.c | 257 |
1 files changed, 0 insertions, 257 deletions
diff --git a/src/glu/sgi/libtess/normal.c b/src/glu/sgi/libtess/normal.c deleted file mode 100644 index 9a3bd43d3c9..00000000000 --- a/src/glu/sgi/libtess/normal.c +++ /dev/null @@ -1,257 +0,0 @@ -/* - * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008) - * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved. - * - * Permission is hereby granted, free of charge, to any person obtaining a - * copy of this software and associated documentation files (the "Software"), - * to deal in the Software without restriction, including without limitation - * the rights to use, copy, modify, merge, publish, distribute, sublicense, - * and/or sell copies of the Software, and to permit persons to whom the - * Software is furnished to do so, subject to the following conditions: - * - * The above copyright notice including the dates of first publication and - * either this permission notice or a reference to - * http://oss.sgi.com/projects/FreeB/ - * shall be included in all copies or substantial portions of the Software. - * - * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS - * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, - * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL - * SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, - * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF - * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE - * SOFTWARE. - * - * Except as contained in this notice, the name of Silicon Graphics, Inc. - * shall not be used in advertising or otherwise to promote the sale, use or - * other dealings in this Software without prior written authorization from - * Silicon Graphics, Inc. - */ -/* -** Author: Eric Veach, July 1994. -** -*/ - -#include "gluos.h" -#include "mesh.h" -#include "tess.h" -#include "normal.h" -#include <math.h> -#include <assert.h> - -#ifndef TRUE -#define TRUE 1 -#endif -#ifndef FALSE -#define FALSE 0 -#endif - -#define Dot(u,v) (u[0]*v[0] + u[1]*v[1] + u[2]*v[2]) - -#if 0 -static void Normalize( GLdouble v[3] ) -{ - GLdouble len = v[0]*v[0] + v[1]*v[1] + v[2]*v[2]; - - assert( len > 0 ); - len = sqrt( len ); - v[0] /= len; - v[1] /= len; - v[2] /= len; -} -#endif - -#undef ABS -#define ABS(x) ((x) < 0 ? -(x) : (x)) - -static int LongAxis( GLdouble v[3] ) -{ - int i = 0; - - if( ABS(v[1]) > ABS(v[0]) ) { i = 1; } - if( ABS(v[2]) > ABS(v[i]) ) { i = 2; } - return i; -} - -static void ComputeNormal( GLUtesselator *tess, GLdouble norm[3] ) -{ - GLUvertex *v, *v1, *v2; - GLdouble c, tLen2, maxLen2; - GLdouble maxVal[3], minVal[3], d1[3], d2[3], tNorm[3]; - GLUvertex *maxVert[3], *minVert[3]; - GLUvertex *vHead = &tess->mesh->vHead; - int i; - - maxVal[0] = maxVal[1] = maxVal[2] = -2 * GLU_TESS_MAX_COORD; - minVal[0] = minVal[1] = minVal[2] = 2 * GLU_TESS_MAX_COORD; - - for( v = vHead->next; v != vHead; v = v->next ) { - for( i = 0; i < 3; ++i ) { - c = v->coords[i]; - if( c < minVal[i] ) { minVal[i] = c; minVert[i] = v; } - if( c > maxVal[i] ) { maxVal[i] = c; maxVert[i] = v; } - } - } - - /* Find two vertices separated by at least 1/sqrt(3) of the maximum - * distance between any two vertices - */ - i = 0; - if( maxVal[1] - minVal[1] > maxVal[0] - minVal[0] ) { i = 1; } - if( maxVal[2] - minVal[2] > maxVal[i] - minVal[i] ) { i = 2; } - if( minVal[i] >= maxVal[i] ) { - /* All vertices are the same -- normal doesn't matter */ - norm[0] = 0; norm[1] = 0; norm[2] = 1; - return; - } - - /* Look for a third vertex which forms the triangle with maximum area - * (Length of normal == twice the triangle area) - */ - maxLen2 = 0; - v1 = minVert[i]; - v2 = maxVert[i]; - d1[0] = v1->coords[0] - v2->coords[0]; - d1[1] = v1->coords[1] - v2->coords[1]; - d1[2] = v1->coords[2] - v2->coords[2]; - for( v = vHead->next; v != vHead; v = v->next ) { - d2[0] = v->coords[0] - v2->coords[0]; - d2[1] = v->coords[1] - v2->coords[1]; - d2[2] = v->coords[2] - v2->coords[2]; - tNorm[0] = d1[1]*d2[2] - d1[2]*d2[1]; - tNorm[1] = d1[2]*d2[0] - d1[0]*d2[2]; - tNorm[2] = d1[0]*d2[1] - d1[1]*d2[0]; - tLen2 = tNorm[0]*tNorm[0] + tNorm[1]*tNorm[1] + tNorm[2]*tNorm[2]; - if( tLen2 > maxLen2 ) { - maxLen2 = tLen2; - norm[0] = tNorm[0]; - norm[1] = tNorm[1]; - norm[2] = tNorm[2]; - } - } - - if( maxLen2 <= 0 ) { - /* All points lie on a single line -- any decent normal will do */ - norm[0] = norm[1] = norm[2] = 0; - norm[LongAxis(d1)] = 1; - } -} - - -static void CheckOrientation( GLUtesselator *tess ) -{ - GLdouble area; - GLUface *f, *fHead = &tess->mesh->fHead; - GLUvertex *v, *vHead = &tess->mesh->vHead; - GLUhalfEdge *e; - - /* When we compute the normal automatically, we choose the orientation - * so that the sum of the signed areas of all contours is non-negative. - */ - area = 0; - for( f = fHead->next; f != fHead; f = f->next ) { - e = f->anEdge; - if( e->winding <= 0 ) continue; - do { - area += (e->Org->s - e->Dst->s) * (e->Org->t + e->Dst->t); - e = e->Lnext; - } while( e != f->anEdge ); - } - if( area < 0 ) { - /* Reverse the orientation by flipping all the t-coordinates */ - for( v = vHead->next; v != vHead; v = v->next ) { - v->t = - v->t; - } - tess->tUnit[0] = - tess->tUnit[0]; - tess->tUnit[1] = - tess->tUnit[1]; - tess->tUnit[2] = - tess->tUnit[2]; - } -} - -#ifdef FOR_TRITE_TEST_PROGRAM -#include <stdlib.h> -extern int RandomSweep; -#define S_UNIT_X (RandomSweep ? (2*drand48()-1) : 1.0) -#define S_UNIT_Y (RandomSweep ? (2*drand48()-1) : 0.0) -#else -#if defined(SLANTED_SWEEP) -/* The "feature merging" is not intended to be complete. There are - * special cases where edges are nearly parallel to the sweep line - * which are not implemented. The algorithm should still behave - * robustly (ie. produce a reasonable tesselation) in the presence - * of such edges, however it may miss features which could have been - * merged. We could minimize this effect by choosing the sweep line - * direction to be something unusual (ie. not parallel to one of the - * coordinate axes). - */ -#define S_UNIT_X 0.50941539564955385 /* Pre-normalized */ -#define S_UNIT_Y 0.86052074622010633 -#else -#define S_UNIT_X 1.0 -#define S_UNIT_Y 0.0 -#endif -#endif - -/* Determine the polygon normal and project vertices onto the plane - * of the polygon. - */ -void __gl_projectPolygon( GLUtesselator *tess ) -{ - GLUvertex *v, *vHead = &tess->mesh->vHead; - GLdouble norm[3]; - GLdouble *sUnit, *tUnit; - int i, computedNormal = FALSE; - - norm[0] = tess->normal[0]; - norm[1] = tess->normal[1]; - norm[2] = tess->normal[2]; - if( norm[0] == 0 && norm[1] == 0 && norm[2] == 0 ) { - ComputeNormal( tess, norm ); - computedNormal = TRUE; - } - sUnit = tess->sUnit; - tUnit = tess->tUnit; - i = LongAxis( norm ); - -#if defined(FOR_TRITE_TEST_PROGRAM) || defined(TRUE_PROJECT) - /* Choose the initial sUnit vector to be approximately perpendicular - * to the normal. - */ - Normalize( norm ); - - sUnit[i] = 0; - sUnit[(i+1)%3] = S_UNIT_X; - sUnit[(i+2)%3] = S_UNIT_Y; - - /* Now make it exactly perpendicular */ - w = Dot( sUnit, norm ); - sUnit[0] -= w * norm[0]; - sUnit[1] -= w * norm[1]; - sUnit[2] -= w * norm[2]; - Normalize( sUnit ); - - /* Choose tUnit so that (sUnit,tUnit,norm) form a right-handed frame */ - tUnit[0] = norm[1]*sUnit[2] - norm[2]*sUnit[1]; - tUnit[1] = norm[2]*sUnit[0] - norm[0]*sUnit[2]; - tUnit[2] = norm[0]*sUnit[1] - norm[1]*sUnit[0]; - Normalize( tUnit ); -#else - /* Project perpendicular to a coordinate axis -- better numerically */ - sUnit[i] = 0; - sUnit[(i+1)%3] = S_UNIT_X; - sUnit[(i+2)%3] = S_UNIT_Y; - - tUnit[i] = 0; - tUnit[(i+1)%3] = (norm[i] > 0) ? -S_UNIT_Y : S_UNIT_Y; - tUnit[(i+2)%3] = (norm[i] > 0) ? S_UNIT_X : -S_UNIT_X; -#endif - - /* Project the vertices onto the sweep plane */ - for( v = vHead->next; v != vHead; v = v->next ) { - v->s = Dot( v->coords, sUnit ); - v->t = Dot( v->coords, tUnit ); - } - if( computedNormal ) { - CheckOrientation( tess ); - } -} |