Marching Cubes 二义性

/* $Id: gl2ps.c,v 1.1.1.1 2006/04/03 23:59:24 CVS Exp $ */ /* * GL2PS, an OpenGL to PostScript Printing Library * Copyright (C) 1999-2004 Christophe Geuzaine <geuz@geuz.org> * * This program is free software; you can redistribute it and/or * modify it under the terms of either: * * a) the GNU Library General Public License as published by the Free * Software Foundation, either version 2 of the License, or (at your * option) any later version; or * * b) the GL2PS License as published by Christophe Geuzaine, either * version 2 of the License, or (at your option) any later version. * * This program 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 either * the GNU Library General Public License or the GL2PS License for * more details. * * You should have received a copy of the GNU Library General Public * License along with this library in the file named "COPYING.LGPL"; * if not, write to the Free Software Foundation, Inc., 675 Mass Ave, * Cambridge, MA 02139, USA. * * You should have received a copy of the GL2PS License with this * library in the file named "COPYING.GL2PS"; if not, I will be glad * to provide one. * * Contributors: * Michael Sweet <mike@easysw.com> * Marc Ume <marc.ume@digitalgraphics.be> * Jean-Francois Remacle <remacle@gce.ucl.ac.be> * Bart Kaptein <B.L.Kaptein@lumc.nl> * Quy Nguyen-Dai <quy@nguyendai.org> * Sam Buss <sbuss@ucsd.edu> * Shane Hill <Shane.Hill@dsto.defence.gov.au> * Romain Boman <r_boman@yahoo.fr> * Rouben Rostamian <rostamian@umbc.edu> * Diego Santa Cruz <Diego.SantaCruz@epfl.ch> * Shahzad Muzaffar <Shahzad.Muzaffar@cern.ch> * Lassi Tuura <lassi.tuura@cern.ch> * Guy Barrand <barrand@lal.in2p3.fr> * Prabhu Ramachandran <prabhu@aero.iitm.ernet.in> * Micha Bieber <bieber@traits.de> * * For the latest info about gl2ps, see http://www.geuz.org/gl2ps/. * Please report all bugs and problems to <gl2ps@geuz.org>. */ #if !defined(WIN32) || defined(__CYGWIN__) #pragma implementation #endif // WIN32 #include <math.h> #include <string.h> #include <sys/types.h> #include <stdarg.h> #include <time.h> #include <float.h> #include "gl2ps.h" /********************************************************************* * * Private definitions, data structures and prototypes * *********************************************************************/ /* Magic numbers (assuming that the order of magnitude of window coordinates is 10^3) */ #define GL2PS_EPSILON 5.0e-3F #define GL2PS_ZSCALE 1000.0F #define GL2PS_ZOFFSET 1.0F #define GL2PS_ZOFFSET_LARGE 20.0F #define GL2PS_ZERO(arg) (fabs(arg) < 1.e-20) /* Primitive types */ #define GL2PS_NOTYPE -1 #define GL2PS_TEXT 1 #define GL2PS_POINT 2 #define GL2PS_LINE 3 #define GL2PS_QUADRANGLE 4 #define GL2PS_TRIANGLE 5 #define GL2PS_PIXMAP 6 #define GL2PS_IMAGEMAP 7 #define GL2PS_IMAGEMAP_WRITTEN 8 #define GL2PS_IMAGEMAP_VISIBLE 9 /* BSP tree primitive comparison */ #define GL2PS_COINCIDENT 1 #define GL2PS_IN_FRONT_OF 2 #define GL2PS_IN_BACK_OF 3 #define GL2PS_SPANNING 4 /* 2D BSP tree primitive comparison */ #define GL2PS_POINT_COINCIDENT 0 #define GL2PS_POINT_INFRONT 1 #define GL2PS_POINT_BACK 2 /* Pass through options */ #define GL2PS_BEGIN_POLYGON_OFFSET_FILL 1 #define GL2PS_END_POLYGON_OFFSET_FILL 2 #define GL2PS_BEGIN_POLYGON_BOUNDARY 3 #define GL2PS_END_POLYGON_BOUNDARY 4 #define GL2PS_BEGIN_LINE_STIPPLE 5 #define GL2PS_END_LINE_STIPPLE 6 #define GL2PS_SET_POINT_SIZE 7 #define GL2PS_SET_LINE_WIDTH 8 #define GL2PS_BEGIN_BLEND 9 #define GL2PS_END_BLEND 10 #define GL2PS_SRC_BLEND 11 #define GL2PS_DST_BLEND 12 #define GL2PS_DRAW_IMAGEMAP_TOKEN 13 typedef enum { T_UNDEFINED = -1, T_CONST_COLOR = 1, T_VAR_COLOR = 1<<1, T_ALPHA_1 = 1<<2, T_ALPHA_LESS_1 = 1<<3, T_VAR_ALPHA = 1<<4 } GL2PS_TRIANGLE_PROPERTY; typedef GLfloat GL2PSxyz[3]; typedef GLfloat GL2PSplane[4]; typedef struct _GL2PSbsptree2d GL2PSbsptree2d; struct _GL2PSbsptree2d { GL2PSplane plane; GL2PSbsptree2d *front, *back; }; typedef struct { GLint nmax, size, incr, n; char *array; } GL2PSlist; typedef struct _GL2PSbsptree GL2PSbsptree; struct _GL2PSbsptree { GL2PSplane plane; GL2PSlist *primitives; GL2PSbsptree *front, *back; }; typedef struct { GL2PSxyz xyz; GL2PSrgba rgba; } GL2PSvertex; typedef struct { GL2PSvertex vertex[3]; int prop; } GL2PStriangle; typedef struct { GLshort fontsize; char *str, *fontname; GLint alignment; GLfloat angle; } GL2PSstring; /* FIXME: in the case of an image map, "type" indicates if this image map has already been written to the PostScript file or not, and "format" indicates if this image map is visible or not */ typedef struct { GLsizei width, height; GLenum format, type; GLfloat *pixels; } GL2PSimage; typedef struct _GL2PSimagemap GL2PSimagemap; struct _GL2PSimagemap { GL2PSimage *image; GL2PSimagemap *next; }; typedef struct { GLshort type, numverts; GLushort pattern; char boundary, offset, culled; GLint factor; GLfloat width; GL2PSvertex *verts; union { GL2PSstring *text; GL2PSimage *image; } data; } GL2PSprimitive; typedef struct { #ifdef GL2PS_HAVE_ZLIB Bytef *dest, *src, *start; uLongf destLen, srcLen; #else int dummy; #endif } GL2PScompress; typedef struct{ GL2PSlist* ptrlist; int gsno, fontno, imno, shno, maskshno, trgroupno; int gsobjno, fontobjno, imobjno, shobjno, maskshobjno, trgroupobjno; } GL2PSpdfgroup; typedef struct { /* General */ GLint format, sort, options, colorsize, colormode, buffersize; char *title, *producer, *filename; GLboolean boundary, blending; GLfloat *feedback, offset[2], lastlinewidth; GLint viewport[4], blendfunc[2], lastfactor; GL2PSrgba *colormap, lastrgba, threshold; GLushort lastpattern; GL2PSlist *primitives; FILE *stream; GL2PScompress *compress; /* BSP-specific */ GLint maxbestroot; /* Occlusion culling-specific */ GLboolean zerosurfacearea; GL2PSbsptree2d *imagetree; GL2PSprimitive *primitivetoadd; /* PDF-specific */ int streamlength; GL2PSlist *pdfprimlist, *pdfgrouplist; int *xreflist; int objects_stack; /* available objects */ int extgs_stack; /* graphics state object number */ int font_stack; /* font object number */ int im_stack; /* image object number */ int trgroupobjects_stack; /* xobject numbers */ int shader_stack; /* shader object numbers */ int mshader_stack; /* mask shader object numbers */ /* for image map list */ GL2PSimagemap *imagemap_head; GL2PSimagemap *imagemap_tail; } GL2PScontext; /* The gl2ps context. gl2ps is not thread safe (we should create a local GL2PScontext during gl2psBeginPage) */ static GL2PScontext *gl2ps = NULL; /* Need to forward declare this one */ static GLint gl2psPrintPrimitives(void); /********************************************************************* * * Utility routines * *********************************************************************/ static void gl2psMsg(GLint level, char *fmt, ...) { va_list args; if(!(gl2ps->options & GL2PS_SILENT)){ switch(level){ case GL2PS_INFO : fprintf(stderr, "GL2PS info: "); break; case GL2PS_WARNING : fprintf(stderr, "GL2PS warning: "); break; case GL2PS_ERROR : fprintf(stderr, "GL2PS error: "); break; } va_start(args, fmt); vfprintf(stderr, fmt, args