00001 /*****************************************************************************/ 00002 /* */ 00003 /* (triangle.h) */ 00004 /* */ 00005 /* Include file for programs that call Triangle. */ 00006 /* */ 00007 /* Accompanies Triangle Version 1.6 */ 00008 /* July 28, 2005 */ 00009 /* */ 00010 /* Copyright 1996, 2005 */ 00011 /* Jonathan Richard Shewchuk */ 00012 /* 2360 Woolsey #H */ 00013 /* Berkeley, California 94705-1927 */ 00014 /* jrs@cs.berkeley.edu */ 00015 /* */ 00016 /*****************************************************************************/ 00017 00018 /*****************************************************************************/ 00019 /* */ 00020 /* How to call Triangle from another program */ 00021 /* */ 00022 /* */ 00023 /* If you haven't read Triangle's instructions (run "triangle -h" to read */ 00024 /* them), you won't understand what follows. */ 00025 /* */ 00026 /* Triangle must be compiled into an object file (triangle.o) with the */ 00027 /* TRILIBRARY symbol defined (generally by using the -DTRILIBRARY compiler */ 00028 /* switch). The makefile included with Triangle will do this for you if */ 00029 /* you run "make trilibrary". The resulting object file can be called via */ 00030 /* the procedure triangulate(). */ 00031 /* */ 00032 /* If the size of the object file is important to you, you may wish to */ 00033 /* generate a reduced version of triangle.o. The REDUCED symbol gets rid */ 00034 /* of all features that are primarily of research interest. Specifically, */ 00035 /* the -DREDUCED switch eliminates Triangle's -i, -F, -s, and -C switches. */ 00036 /* The CDT_ONLY symbol gets rid of all meshing algorithms above and beyond */ 00037 /* constrained Delaunay triangulation. Specifically, the -DCDT_ONLY switch */ 00038 /* eliminates Triangle's -r, -q, -a, -u, -D, -Y, -S, and -s switches. */ 00039 /* */ 00040 /* IMPORTANT: These definitions (TRILIBRARY, REDUCED, CDT_ONLY) must be */ 00041 /* made in the makefile or in triangle.c itself. Putting these definitions */ 00042 /* in this file (triangle.h) will not create the desired effect. */ 00043 /* */ 00044 /* */ 00045 /* The calling convention for triangulate() follows. */ 00046 /* */ 00047 /* void triangulate(triswitches, in, out, vorout) */ 00048 /* char *triswitches; */ 00049 /* struct triangulateio *in; */ 00050 /* struct triangulateio *out; */ 00051 /* struct triangulateio *vorout; */ 00052 /* */ 00053 /* `triswitches' is a string containing the command line switches you wish */ 00054 /* to invoke. No initial dash is required. Some suggestions: */ 00055 /* */ 00056 /* - You'll probably find it convenient to use the `z' switch so that */ 00057 /* points (and other items) are numbered from zero. This simplifies */ 00058 /* indexing, because the first item of any type always starts at index */ 00059 /* [0] of the corresponding array, whether that item's number is zero or */ 00060 /* one. */ 00061 /* - You'll probably want to use the `Q' (quiet) switch in your final code, */ 00062 /* but you can take advantage of Triangle's printed output (including the */ 00063 /* `V' switch) while debugging. */ 00064 /* - If you are not using the `q', `a', `u', `D', `j', or `s' switches, */ 00065 /* then the output points will be identical to the input points, except */ 00066 /* possibly for the boundary markers. If you don't need the boundary */ 00067 /* markers, you should use the `N' (no nodes output) switch to save */ 00068 /* memory. (If you do need boundary markers, but need to save memory, a */ 00069 /* good nasty trick is to set out->pointlist equal to in->pointlist */ 00070 /* before calling triangulate(), so that Triangle overwrites the input */ 00071 /* points with identical copies.) */ 00072 /* - The `I' (no iteration numbers) and `g' (.off file output) switches */ 00073 /* have no effect when Triangle is compiled with TRILIBRARY defined. */ 00074 /* */ 00075 /* `in', `out', and `vorout' are descriptions of the input, the output, */ 00076 /* and the Voronoi output. If the `v' (Voronoi output) switch is not used, */ 00077 /* `vorout' may be NULL. `in' and `out' may never be NULL. */ 00078 /* */ 00079 /* Certain fields of the input and output structures must be initialized, */ 00080 /* as described below. */ 00081 /* */ 00082 /*****************************************************************************/ 00083 00084 /*****************************************************************************/ 00085 /* */ 00086 /* The `triangulateio' structure. */ 00087 /* */ 00088 /* Used to pass data into and out of the triangulate() procedure. */ 00089 /* */ 00090 /* */ 00091 /* Arrays are used to store points, triangles, markers, and so forth. In */ 00092 /* all cases, the first item in any array is stored starting at index [0]. */ 00093 /* However, that item is item number `1' unless the `z' switch is used, in */ 00094 /* which case it is item number `0'. Hence, you may find it easier to */ 00095 /* index points (and triangles in the neighbor list) if you use the `z' */ 00096 /* switch. Unless, of course, you're calling Triangle from a Fortran */ 00097 /* program. */ 00098 /* */ 00099 /* Description of fields (except the `numberof' fields, which are obvious): */ 00100 /* */ 00101 /* `pointlist': An array of point coordinates. The first point's x */ 00102 /* coordinate is at index [0] and its y coordinate at index [1], followed */ 00103 /* by the coordinates of the remaining points. Each point occupies two */ 00104 /* REALs. */ 00105 /* `pointattributelist': An array of point attributes. Each point's */ 00106 /* attributes occupy `numberofpointattributes' REALs. */ 00107 /* `pointmarkerlist': An array of point markers; one int per point. */ 00108 /* */ 00109 /* `trianglelist': An array of triangle corners. The first triangle's */ 00110 /* first corner is at index [0], followed by its other two corners in */ 00111 /* counterclockwise order, followed by any other nodes if the triangle */ 00112 /* represents a nonlinear element. Each triangle occupies */ 00113 /* `numberofcorners' ints. */ 00114 /* `triangleattributelist': An array of triangle attributes. Each */ 00115 /* triangle's attributes occupy `numberoftriangleattributes' REALs. */ 00116 /* `trianglearealist': An array of triangle area constraints; one REAL per */ 00117 /* triangle. Input only. */ 00118 /* `neighborlist': An array of triangle neighbors; three ints per */ 00119 /* triangle. Output only. */ 00120 /* */ 00121 /* `segmentlist': An array of segment endpoints. The first segment's */ 00122 /* endpoints are at indices [0] and [1], followed by the remaining */ 00123 /* segments. Two ints per segment. */ 00124 /* `segmentmarkerlist': An array of segment markers; one int per segment. */ 00125 /* */ 00126 /* `holelist': An array of holes. The first hole's x and y coordinates */ 00127 /* are at indices [0] and [1], followed by the remaining holes. Two */ 00128 /* REALs per hole. Input only, although the pointer is copied to the */ 00129 /* output structure for your convenience. */ 00130 /* */ 00131 /* `regionlist': An array of regional attributes and area constraints. */ 00132 /* The first constraint's x and y coordinates are at indices [0] and [1], */ 00133 /* followed by the regional attribute at index [2], followed by the */ 00134 /* maximum area at index [3], followed by the remaining area constraints. */ 00135 /* Four REALs per area constraint. Note that each regional attribute is */ 00136 /* used only if you select the `A' switch, and each area constraint is */ 00137 /* used only if you select the `a' switch (with no number following), but */ 00138 /* omitting one of these switches does not change the memory layout. */ 00139 /* Input only, although the pointer is copied to the output structure for */ 00140 /* your convenience. */ 00141 /* */ 00142 /* `edgelist': An array of edge endpoints. The first edge's endpoints are */ 00143 /* at indices [0] and [1], followed by the remaining edges. Two ints per */ 00144 /* edge. Output only. */ 00145 /* `edgemarkerlist': An array of edge markers; one int per edge. Output */ 00146 /* only. */ 00147 /* `normlist': An array of normal vectors, used for infinite rays in */ 00148 /* Voronoi diagrams. The first normal vector's x and y magnitudes are */ 00149 /* at indices [0] and [1], followed by the remaining vectors. For each */ 00150 /* finite edge in a Voronoi diagram, the normal vector written is the */ 00151 /* zero vector. Two REALs per edge. Output only. */ 00152 /* */ 00153 /* */ 00154 /* Any input fields that Triangle will examine must be initialized. */ 00155 /* Furthermore, for each output array that Triangle will write to, you */ 00156 /* must either provide space by setting the appropriate pointer to point */ 00157 /* to the space you want the data written to, or you must initialize the */ 00158 /* pointer to NULL, which tells Triangle to allocate space for the results. */ 00159 /* The latter option is preferable, because Triangle always knows exactly */ 00160 /* how much space to allocate. The former option is provided mainly for */ 00161 /* people who need to call Triangle from Fortran code, though it also makes */ 00162 /* possible some nasty space-saving tricks, like writing the output to the */ 00163 /* same arrays as the input. */ 00164 /* */ 00165 /* Triangle will not free() any input or output arrays, including those it */ 00166 /* allocates itself; that's up to you. You should free arrays allocated by */ 00167 /* Triangle by calling the trifree() procedure defined below. (By default, */ 00168 /* trifree() just calls the standard free() library procedure, but */ 00169 /* applications that call triangulate() may replace trimalloc() and */ 00170 /* trifree() in triangle.c to use specialized memory allocators.) */ 00171 /* */ 00172 /* Here's a guide to help you decide which fields you must initialize */ 00173 /* before you call triangulate(). */ 00174 /* */ 00175 /* `in': */ 00176 /* */ 00177 /* - `pointlist' must always point to a list of points; `numberofpoints' */ 00178 /* and `numberofpointattributes' must be properly set. */ 00179 /* `pointmarkerlist' must either be set to NULL (in which case all */ 00180 /* markers default to zero), or must point to a list of markers. If */ 00181 /* `numberofpointattributes' is not zero, `pointattributelist' must */ 00182 /* point to a list of point attributes. */ 00183 /* - If the `r' switch is used, `trianglelist' must point to a list of */ 00184 /* triangles, and `numberoftriangles', `numberofcorners', and */ 00185 /* `numberoftriangleattributes' must be properly set. If */ 00186 /* `numberoftriangleattributes' is not zero, `triangleattributelist' */ 00187 /* must point to a list of triangle attributes. If the `a' switch is */ 00188 /* used (with no number following), `trianglearealist' must point to a */ 00189 /* list of triangle area constraints. `neighborlist' may be ignored. */ 00190 /* - If the `p' switch is used, `segmentlist' must point to a list of */ 00191 /* segments, `numberofsegments' must be properly set, and */ 00192 /* `segmentmarkerlist' must either be set to NULL (in which case all */ 00193 /* markers default to zero), or must point to a list of markers. */ 00194 /* - If the `p' switch is used without the `r' switch, then */ 00195 /* `numberofholes' and `numberofregions' must be properly set. If */ 00196 /* `numberofholes' is not zero, `holelist' must point to a list of */ 00197 /* holes. If `numberofregions' is not zero, `regionlist' must point to */ 00198 /* a list of region constraints. */ 00199 /* - If the `p' switch is used, `holelist', `numberofholes', */ 00200 /* `regionlist', and `numberofregions' is copied to `out'. (You can */ 00201 /* nonetheless get away with not initializing them if the `r' switch is */ 00202 /* used.) */ 00203 /* - `edgelist', `edgemarkerlist', `normlist', and `numberofedges' may be */ 00204 /* ignored. */ 00205 /* */ 00206 /* `out': */ 00207 /* */ 00208 /* - `pointlist' must be initialized (NULL or pointing to memory) unless */ 00209 /* the `N' switch is used. `pointmarkerlist' must be initialized */ 00210 /* unless the `N' or `B' switch is used. If `N' is not used and */ 00211 /* `in->numberofpointattributes' is not zero, `pointattributelist' must */ 00212 /* be initialized. */ 00213 /* - `trianglelist' must be initialized unless the `E' switch is used. */ 00214 /* `neighborlist' must be initialized if the `n' switch is used. If */ 00215 /* the `E' switch is not used and (`in->numberofelementattributes' is */ 00216 /* not zero or the `A' switch is used), `elementattributelist' must be */ 00217 /* initialized. `trianglearealist' may be ignored. */ 00218 /* - `segmentlist' must be initialized if the `p' or `c' switch is used, */ 00219 /* and the `P' switch is not used. `segmentmarkerlist' must also be */ 00220 /* initialized under these circumstances unless the `B' switch is used. */ 00221 /* - `edgelist' must be initialized if the `e' switch is used. */ 00222 /* `edgemarkerlist' must be initialized if the `e' switch is used and */ 00223 /* the `B' switch is not. */ 00224 /* - `holelist', `regionlist', `normlist', and all scalars may be ignored.*/ 00225 /* */ 00226 /* `vorout' (only needed if `v' switch is used): */ 00227 /* */ 00228 /* - `pointlist' must be initialized. If `in->numberofpointattributes' */ 00229 /* is not zero, `pointattributelist' must be initialized. */ 00230 /* `pointmarkerlist' may be ignored. */ 00231 /* - `edgelist' and `normlist' must both be initialized. */ 00232 /* `edgemarkerlist' may be ignored. */ 00233 /* - Everything else may be ignored. */ 00234 /* */ 00235 /* After a call to triangulate(), the valid fields of `out' and `vorout' */ 00236 /* will depend, in an obvious way, on the choice of switches used. Note */ 00237 /* that when the `p' switch is used, the pointers `holelist' and */ 00238 /* `regionlist' are copied from `in' to `out', but no new space is */ 00239 /* allocated; be careful that you don't free() the same array twice. On */ 00240 /* the other hand, Triangle will never copy the `pointlist' pointer (or any */ 00241 /* others); new space is allocated for `out->pointlist', or if the `N' */ 00242 /* switch is used, `out->pointlist' remains uninitialized. */ 00243 /* */ 00244 /* All of the meaningful `numberof' fields will be properly set; for */ 00245 /* instance, `numberofedges' will represent the number of edges in the */ 00246 /* triangulation whether or not the edges were written. If segments are */ 00247 /* not used, `numberofsegments' will indicate the number of boundary edges. */ 00248 /* */ 00249 /*****************************************************************************/ 00250 00251 struct triangulateio { 00252 REAL *pointlist; /* In / out */ 00253 REAL *pointattributelist; /* In / out */ 00254 int *pointmarkerlist; /* In / out */ 00255 int numberofpoints; /* In / out */ 00256 int numberofpointattributes; /* In / out */ 00257 00258 int *trianglelist; /* In / out */ 00259 REAL *triangleattributelist; /* In / out */ 00260 REAL *trianglearealist; /* In only */ 00261 int *neighborlist; /* Out only */ 00262 int numberoftriangles; /* In / out */ 00263 int numberofcorners; /* In / out */ 00264 int numberoftriangleattributes; /* In / out */ 00265 00266 int *segmentlist; /* In / out */ 00267 int *segmentmarkerlist; /* In / out */ 00268 int numberofsegments; /* In / out */ 00269 00270 REAL *holelist; /* In / pointer to array copied out */ 00271 int numberofholes; /* In / copied out */ 00272 00273 REAL *regionlist; /* In / pointer to array copied out */ 00274 int numberofregions; /* In / copied out */ 00275 00276 int *edgelist; /* Out only */ 00277 int *edgemarkerlist; /* Not used with Voronoi diagram; out only */ 00278 REAL *normlist; /* Used only with Voronoi diagram; out only */ 00279 int numberofedges; /* Out only */ 00280 }; 00281 00282 #ifdef ANSI_DECLARATORS 00283 void triangulate(char *, struct triangulateio *, struct triangulateio *, 00284 struct triangulateio *); 00285 void trifree(VOID *memptr); 00286 #else /* not ANSI_DECLARATORS */ 00287 void triangulate(); 00288 void trifree(); 00289 #endif /* not ANSI_DECLARATORS */