Edit
IABSD.fr/xenocara/lib/libGLU/src/libnurbs/internals/splitarcs.cc
jsg
- lib/libGLU/src/libnurbs/internals/splitarcs.cc
-
/* ** License Applicability. Except to the extent portions of this file are ** made subject to an alternative license as permitted in the SGI Free ** Software License B, Version 1.1 (the "License"), the contents of this ** file are subject only to the provisions of the License. You may not use ** this file except in compliance with the License. You may obtain a copy ** of the License at Silicon Graphics, Inc., attn: Legal Services, 1600 ** Amphitheatre Parkway, Mountain View, CA 94043-1351, or at: ** ** http://oss.sgi.com/projects/FreeB ** ** Note that, as provided in the License, the Software is distributed on an ** "AS IS" basis, with ALL EXPRESS AND IMPLIED WARRANTIES AND CONDITIONS ** DISCLAIMED, INCLUDING, WITHOUT LIMITATION, ANY IMPLIED WARRANTIES AND ** CONDITIONS OF MERCHANTABILITY, SATISFACTORY QUALITY, FITNESS FOR A ** PARTICULAR PURPOSE, AND NON-INFRINGEMENT. ** ** Original Code. The Original Code is: OpenGL Sample Implementation, ** Version 1.2.1, released January 26, 2000, developed by Silicon Graphics, ** Inc. The Original Code is Copyright (c) 1991-2000 Silicon Graphics, Inc. ** Copyright in any portions created by third parties is as indicated ** elsewhere herein. All Rights Reserved. ** ** Additional Notice Provisions: The application programming interfaces ** established by SGI in conjunction with the Original Code are The ** OpenGL(R) Graphics System: A Specification (Version 1.2.1), released ** April 1, 1999; The OpenGL(R) Graphics System Utility Library (Version ** 1.3), released November 4, 1998; and OpenGL(R) Graphics with the X ** Window System(R) (Version 1.3), released October 19, 1998. This software ** was created using the OpenGL(R) version 1.2.1 Sample Implementation ** published by SGI, but has not been independently verified as being ** compliant with the OpenGL(R) version 1.2.1 Specification. */ /* * splitarcs.c++ * */ #include "glimports.h" #include "myassert.h" #include "mysetjmp.h" #include "mystdio.h" #include "subdivider.h" #include "arcsorter.h" #include "arc.h" #include "bin.h" /* local preprocessor definitions */ #define MAXARCS 10 /*---------------------------------------------------------------------------- * Subdivider::split - split trim regions in source bin by line (param == value). *---------------------------------------------------------------------------- */ void Subdivider::split( Bin& bin, Bin& left, Bin& right, int param, REAL value ) { Bin intersections, unknown; partition( bin, left, intersections, right, unknown, param, value ); int count = intersections.numarcs(); if( count % 2 ) { #ifndef NDEBUG left.show( "left" ); intersections.show( "intersections" ); right.show( "right" ); #endif ::mylongjmp( jumpbuffer, 29 ); } Arc_ptr arclist[MAXARCS], *list; if( count >= MAXARCS ) { list = new Arc_ptr[count]; } else { list = arclist; } Arc_ptr jarc, *last, *lptr; for( last = list; (jarc=intersections.removearc()) != NULL; last++ ) *last = jarc; if( param == 0 ) { /* sort into increasing t order */ ArcSdirSorter sorter(*this); sorter.qsort( list, count ); //::qsort ((void *)list, count, sizeof(Arc_ptr), (cmpfunc)compare_s); for( lptr=list; lptr<last; lptr+=2 ) check_s ( lptr[0], lptr[1] ); for( lptr=list; lptr<last; lptr+=2 ) join_s ( left, right, lptr[0], lptr[1] ); for( lptr=list; lptr != last; lptr++ ) { if( ((*lptr)->head()[0] <= value) && ((*lptr)->tail()[0] <= value) ) left.addarc( *lptr ); else right.addarc( *lptr ); } } else { /* sort into decreasing s order */ ArcTdirSorter sorter(*this); sorter.qsort( list, count ); //::qsort ((void *)list, count, sizeof(Arc_ptr), (cmpfunc)compare_t); for( lptr=list; lptr<last; lptr+=2 ) check_t ( lptr[0], lptr[1] ); for( lptr=list; lptr<last; lptr+=2 ) join_t ( left, right, lptr[0], lptr[1] ); for( lptr=list; lptr != last; lptr++ ) { if( ((*lptr)->head()[1] <= value) && ((*lptr)->tail()[1] <= value) ) left.addarc( *lptr ); else right.addarc( *lptr ); } } if( list != arclist ) delete[] list; unknown.adopt(); } void Subdivider::check_s( Arc_ptr jarc1, Arc_ptr jarc2 ) { assert( jarc1->check( ) != 0 ); assert( jarc2->check( ) != 0 ); assert( jarc1->next->check( ) != 0 ); assert( jarc2->next->check( ) != 0 ); assert( jarc1 != jarc2 ); /* XXX - if these assertions fail, it is due to user error or undersampling */ if( ! ( jarc1->tail()[0] < (jarc1)->head()[0] ) ) { #ifndef NDEBUG _glu_dprintf( "s difference %f\n", (jarc1)->tail()[0] - (jarc1)->head()[0] ); #endif ::mylongjmp( jumpbuffer, 28 ); } if( ! ( jarc2->tail()[0] > (jarc2)->head()[0] ) ) { #ifndef NDEBUG _glu_dprintf( "s difference %f\n", (jarc2)->tail()[0] - (jarc2)->head()[0] ); #endif ::mylongjmp( jumpbuffer, 28 ); } } inline void Subdivider::link( Arc_ptr jarc1, Arc_ptr jarc2, Arc_ptr up, Arc_ptr down ) { up->nuid = down->nuid = 0; // XXX up->next = jarc2; down->next = jarc1; up->prev = jarc1->prev; down->prev = jarc2->prev; down->next->prev = down; up->next->prev = up; down->prev->next = down; up->prev->next = up; } inline void Subdivider::simple_link( Arc_ptr jarc1, Arc_ptr jarc2 ) { Arc_ptr tmp = jarc2->prev; jarc2->prev = jarc1->prev; jarc1->prev = tmp; jarc2->prev->next = jarc2; jarc1->prev->next = jarc1; } /*---------------------------------------------------------------------------- * join - add a pair of oppositely directed jordan arcs between two arcs *---------------------------------------------------------------------------- */ void Subdivider::join_s( Bin& left, Bin& right, Arc_ptr jarc1, Arc_ptr jarc2 ) { assert( jarc1->check( ) != 0); assert( jarc2->check( ) != 0); assert( jarc1 != jarc2 ); if( ! jarc1->getitail() ) jarc1 = jarc1->next; if( ! jarc2->getitail() ) jarc2 = jarc2->next; REAL s = jarc1->tail()[0]; REAL t1 = jarc1->tail()[1]; REAL t2 = jarc2->tail()[1]; if( t1 == t2 ) { simple_link( jarc1, jarc2 ); } else { Arc_ptr newright = new(arcpool) Arc( arc_right, 0 ); Arc_ptr newleft = new(arcpool) Arc( arc_left, 0 ); assert( t1 < t2 ); if( isBezierArcType() ) { arctessellator.bezier( newright, s, s, t1, t2 ); arctessellator.bezier( newleft, s, s, t2, t1 ); } else { arctessellator.pwl_right( newright, s, t1, t2, stepsizes[0] ); arctessellator.pwl_left( newleft, s, t2, t1, stepsizes[2] ); } link( jarc1, jarc2, newright, newleft ); left.addarc( newright ); right.addarc( newleft ); } assert( jarc1->check( ) != 0 ); assert( jarc2->check( ) != 0 ); assert( jarc1->next->check( ) != 0); assert( jarc2->next->check( ) != 0); } void Subdivider::check_t( Arc_ptr jarc1, Arc_ptr jarc2 ) { assert( jarc1->check( ) != 0 ); assert( jarc2->check( ) != 0 ); assert( jarc1->next->check( ) != 0 ); assert( jarc2->next->check( ) != 0 ); assert( jarc1 != jarc2 ); /* XXX - if these assertions fail, it is due to user error or undersampling */ if( ! ( jarc1->tail()[1] < (jarc1)->head()[1] ) ) { #ifndef NDEBUG _glu_dprintf( "t difference %f\n", jarc1->tail()[1] - (jarc1)->head()[1] ); #endif ::mylongjmp( jumpbuffer, 28 ); } if( ! ( jarc2->tail()[1] > (jarc2)->head()[1] ) ) { #ifndef NDEBUG _glu_dprintf( "t difference %f\n", jarc2->tail()[1] - (jarc2)->head()[1] ); #endif ::mylongjmp( jumpbuffer, 28 ); } } /*---------------------------------------------------------------------------- * join_t - add a pair of oppositely directed jordan arcs between two arcs *---------------------------------------------------------------------------- */ void Subdivider::join_t( Bin& bottom, Bin& top, Arc_ptr jarc1, Arc_ptr jarc2 ) { assert( jarc1->check( ) != 0 ); assert( jarc2->check( ) != 0 ); assert( jarc1->next->check( ) != 0 ); assert( jarc2->next->check( ) != 0 ); assert( jarc1 != jarc2 ); if( ! jarc1->getitail() ) jarc1 = jarc1->next; if( ! jarc2->getitail() ) jarc2 = jarc2->next; REAL s1 = jarc1->tail()[0]; REAL s2 = jarc2->tail()[0]; REAL t = jarc1->tail()[1]; if( s1 == s2 ) { simple_link( jarc1, jarc2 ); } else { Arc_ptr newtop = new(arcpool) Arc( arc_top, 0 ); Arc_ptr newbot = new(arcpool) Arc( arc_bottom, 0 ); assert( s1 > s2 ); if( isBezierArcType() ) { arctessellator.bezier( newtop, s1, s2, t, t ); arctessellator.bezier( newbot, s2, s1, t, t ); } else { arctessellator.pwl_top( newtop, t, s1, s2, stepsizes[1] ); arctessellator.pwl_bottom( newbot, t, s2, s1, stepsizes[3] ); } link( jarc1, jarc2, newtop, newbot ); bottom.addarc( newtop ); top.addarc( newbot ); } assert( jarc1->check( ) != 0 ); assert( jarc2->check( ) != 0 ); assert( jarc1->next->check( ) != 0 ); assert( jarc2->next->check( ) != 0 ); }