source: inundation/ga/storm_surge/pmesh/triangle/triangmodule.c @ 541

/* this appears to be necessary to run on Linux */

#undef _STDLIB_H_
#define _STDLIB_H_


/*
    This code is based on code by A. Pletzer

    This code interfaces pmesh directly with "triangle", a general        
    purpose triangulation code. In doing so, Python data structures          
    are passed to C for  use by "triangle" and the results are then          
    converted back. This was accomplished using the Python/C API.            
                                                                           
    I. Lists of points,edges,holes, and regions must normally be 
     created for proper triangulation. However, if there are no holes,
     the  hole list need not be specified (however, a 
     measure of control over the shape of the convex hull is lost; 
     triangle decides). 
     
     points list: [(x1,y1),(x2,y2),...] (Tuples of doubles)                  
     edge list: [(Ea,Eb),(Ef,Eg),...] (Tuples of integers)                   
     hole list: [(x1,y1),...](Tuples of doubles, one inside each hole region)
     regionlist: [ (x1,y1,index,area),...] (Tuple of doubles)                
     pointattributelist:[ (a1,a2..),...] (Tuple of lists) 
     
     This is all that is needed to accomplish an intial triangulation.       
     A dictionary of the Triangle output is returned.                                   
     Precondition
     End list in the pointattributelist has to have the same length
     
    Compilation can be done as follows                                       
                    
    c++ -I/usr/local/include/python1.5 -shared -o triangmodule.so            
    triangmodule.c triangle.o                                                */


#ifdef SINGLE  
#define REAL float 
#else  
#define REAL double 
#endif  

#include "triangle.h" 

#ifndef _STDLIB_H_ 
#ifndef _WIN32
extern "C" void *malloc(); 
extern "C" void free(); 
#endif
#endif  

#include "Python.h" 


 static PyObject *triang_genMesh(PyObject *self, PyObject *args){
     
  /* Mesh generation routine
     pre-conditions:
     mode must have a 'z' switch, to avoid segmentation faults
  */
    
  struct triangulateio in,out;

  PyObject *hull;
  PyObject *seglist;
  PyObject *holelist;
  PyObject *regionlist;
  PyObject *trianglelist;
  PyObject *mode;
  PyObject *firstPointAttr;
  PyObject *pointattributelist;
  PyObject *segmarkerlist;
  PyObject *Attrlist;
  REAL Attr;
  int i, j, iatt, n;
  int a,b,c;
  int marker;
  int tuplesize;
    
  int index = 0;
  double x,y;
  PyObject *elems;
  PyObject *pair;
     
  char *mod;
  PyObject *holder, *holderlist, *attributelist;
  int listsize,attsize ;
  PyObject  *ii;
     
  if(!PyArg_ParseTuple(args,(char *)"OOOOOOOO",&hull,&seglist,&holelist,&regionlist,&pointattributelist,&segmarkerlist,&trianglelist,&mode)){
    return NULL;
  }
  if(!PyList_Check(hull)){
    PyErr_SetString(PyExc_TypeError, 
                    "incorrect first argument for 'genMesh': list required.");
    return NULL;
  }
  if(!PyList_Check(hull)){
    PyErr_SetString(PyExc_TypeError,
                    "incorrect second argument for 'genMesh': list required.");
    return NULL;
  }
  if(!PyList_Check(hull)){
    PyErr_SetString(PyExc_TypeError,
                    "incorrect third argument for 'genMesh': list required.");
    return NULL;
  }
  if(!PyList_Check(hull)){
    PyErr_SetString(PyExc_TypeError,
                    "incorrect fourth argument for 'genMesh': list required.");
    return NULL;
  }
  if(!PyList_Check(hull)){
    PyErr_SetString(PyExc_TypeError,
                    "incorrect fifth argument for 'genMesh': list required.");
    return NULL;
  }
  if(!PyList_Check(hull)){
    PyErr_SetString(PyExc_TypeError,
                    "incorrect sixth argument for 'genMesh': list required.");
    return NULL;
  }
  if(!PyList_Check(hull)){
    PyErr_SetString(PyExc_TypeError,
                    "incorrect seventh argument for 'genMesh': list required.");
    return NULL;
  }
  if(!PyList_Check(hull)){
    PyErr_SetString(PyExc_TypeError,
                    "incorrect eighth argument for 'genMesh': list required.");
    return NULL;
  }
     
     
  /* Initialize  points */
  in.numberofpoints =  PyList_Size(hull); 
  in.pointlist = (REAL *)malloc(in.numberofpoints*2*sizeof(REAL));
  in.pointmarkerlist = (int *)NULL; /* malloc(in.numberofpoints*sizeof(int)); */
     
  /* Initialize and fill up region list */
  in.numberofregions = PyList_Size(regionlist);
  
  /*printf(" numberofregions %i\n",in.numberofregions );*/
  in.regionlist = (REAL *)malloc(in.numberofregions*4*sizeof(REAL));
  for(i=0; i<in.numberofregions;i++){
    elems = PyList_GetItem(regionlist,i);
    tuplesize = PySequence_Length(elems);
    /*printf("tuplesize %i\n",tuplesize);*/
    if (tuplesize>0){
      in.regionlist[4*i] = PyFloat_AsDouble(PyTuple_GetItem(elems,0));
    } else {
      PyErr_SetString(PyExc_TypeError,
                      "data sent to trianglemodule error: A region has no x value.");
      return NULL;
    }
    if (tuplesize>1){
      in.regionlist[4*i+1] = PyFloat_AsDouble(PyTuple_GetItem(elems,1));
    } else {
      PyErr_SetString(PyExc_TypeError,
                    "data sent to trianglemodule error: A region has no y value.");
      return NULL;
    }
    if (tuplesize>2){
      /* 2 is attribute*/
      in.regionlist[4*i+2] = PyFloat_AsDouble(PyTuple_GetItem(elems,2));
    } else {
      PyErr_SetString(PyExc_TypeError,
                    "data sent to trianglemodule error: A region has no attribute value.");
      return NULL;
    }
    if (tuplesize>3){
      in.regionlist[4*i+3] = PyFloat_AsDouble(PyTuple_GetItem(elems,3));
    } else {
      /* 0.0 is interpreted as no local max area by triangle  */
      in.regionlist[4*i+3] = (REAL)0.0;
    } 
  }
  
  /*Initialize segments */
  in.numberofsegments = PyList_Size(seglist);
  in.segmentlist = (int *)malloc(in.numberofsegments*2*sizeof(int));
  in.segmentmarkerlist = (int *)malloc(in.numberofsegments*sizeof(int));

    
  /*Initialize triangles */
  in.numberofcorners = 3;
  in.numberoftriangles = PyList_Size(trianglelist);
  if (in.numberoftriangles  != 0) {
    in.trianglelist = (int *)malloc(in.numberofsegments*3*sizeof(int));
  } else {
    in.trianglelist = (int *)NULL;
  }
  in.numberoftriangleattributes = 0;  
  in.triangleattributelist  = (REAL *)NULL; 
     
     
     
  /*Initialize holes */
  in.numberofholes = PyList_Size(holelist);
  if (in.numberofholes != 0) {
    in.holelist = (REAL *)malloc(in.numberofholes*2*sizeof(REAL));
  } else {
    in.holelist = (REAL *)NULL;
  }     
     
  /* Fill up triangle list */
  index = 0;
  for(i = 0; i < in.numberoftriangles; i++) {
    pair =  PyList_GetItem(trianglelist,i);
    if (3 != PySequence_Length(pair)) {
      PyErr_SetString(PyExc_TypeError,
                      "data sent to trianglemodule error:Found a triangle without 3 vertices.");
      return NULL;
    }
    a = (int)PyInt_AsLong(PyTuple_GetItem(pair,0));
    in.trianglelist[index] = a;
    index++;
    b = (int)PyInt_AsLong(PyTuple_GetItem(pair,1));
    in.trianglelist[index] = b;
    index++;
    c = (int)PyInt_AsLong(PyTuple_GetItem(pair,2));
    in.trianglelist[index] = c;
    index++;
  }
     
     
  /*  print the triangle list DEBUGGING
      printf ("numberoftriangles %i\n", in.numberoftriangles);
      for(i = 0; i < in.numberoftriangles; i++) {
      printf("(%i,%i,%i)",in.trianglelist[i* 3+ 0],in.trianglelist[i* 3+ 1], in.trianglelist[i* 3+ 2]);
      }*/
     
  /* Fill up segment list */
  index = 0;
  if (in.numberofsegments != PyList_Size(segmarkerlist)) {
    PyErr_SetString(PyExc_TypeError,
                    "data sent to trianglemodule error:number of segments doesn't = number of segment attributes.");
    return NULL;
  }
    
  for(i = 0; i < in.numberofsegments; i++) {
    pair =  PyList_GetItem(seglist,i);
    if (2 != PySequence_Length(pair)) {
      PyErr_SetString(PyExc_TypeError,
                      "data sent to trianglemodule error:Found a segment without 2 vertices.");
      return NULL;
    }
    a = (int)PyInt_AsLong(PyTuple_GetItem(pair,0));
    in.segmentlist[index] = a;
    index++;
    b = (int)PyInt_AsLong(PyTuple_GetItem(pair,1));
    in.segmentlist[index] = b;
    index++;
    /* Fill up segment marker list */
    marker =  (int)PyInt_AsLong(PyList_GetItem(segmarkerlist,i));
    in.segmentmarkerlist[i] = marker;
  }
  /* Fill up hole list */
  index = 0;
  for(i = 0; i < in.numberofholes; i++) {
    pair =  PyList_GetItem(holelist,i);
    if (2 != PySequence_Length(pair)) {
      PyErr_SetString(PyExc_TypeError,
                      "data sent to trianglemodule error:Found a pair without 2 vertices.");
      return NULL;
    }
    x = PyFloat_AsDouble(PyTuple_GetItem(pair,0));
    in.holelist[index] = x;
    index++;
    y = PyFloat_AsDouble(PyTuple_GetItem(pair,1));
    in.holelist[index] = y;
    index++;
  }
     
  /* Fill up point list */
  index = 0;
  for(i = 0; i < in.numberofpoints; i++) {
    pair =  PyList_GetItem(hull,i);
    if (2 != PySequence_Length(pair)) {
      PyErr_SetString(PyExc_TypeError,
                      "data sent to trianglemodule error:Found a vertex without an x,y values.");
      return NULL;
    }
    x = PyFloat_AsDouble(PyTuple_GetItem(pair,0));
    in.pointlist[index] = x;
    index++;
    y = PyFloat_AsDouble(PyTuple_GetItem(pair,1));
    in.pointlist[index] = y;
    index++;
  }

  /* Initialize  point attributes */
/*      firstPointAttr = PyList_GetItem(pointattributelist,0); */
/*      if (firstPointAttr != NULL) { */
/*        //in.numberofpointattributes = PyList_Size(firstPointAttr); */
/*        printf("in.numberofpointattributes =%i",PyList_Size(firstPointAttr)); */
/*        //printf("in.numberofpointattributes =%i",in.numberofpointattributes); */
/*      } else { */
/*        printf("(firstPointAttr is NULL\n"); */
/*        in.pointattributelist = NULL; */
/*        in.numberofpointattributes = 0; */
/*      } */
  n = PyList_Size(pointattributelist);
  if (n < 0) {
    in.numberofpointattributes = 0; 
    in.pointattributelist = (REAL *)NULL;
  } else {
    /* Get the # of attributes based on the size of the first point*/
    firstPointAttr = PyList_GetItem(pointattributelist,0);
    if (firstPointAttr == NULL) {
      in.numberofpointattributes = 0; 
      in.pointattributelist = (REAL *)NULL;
    } else {
      in.numberofpointattributes = PyList_Size(firstPointAttr);
      in.pointattributelist = (REAL *)malloc(in.numberofpoints
                                             *in.numberofpointattributes
                                             *sizeof(REAL)); 
     
     
      /* fill the point attribute list */
      if (in.numberofpointattributes != 0) {
        for(j = 0; j < in.numberofpoints; j++){
          Attrlist = PyList_GetItem(pointattributelist,j);
          if (in.numberofpointattributes != PySequence_Length(Attrlist)) {
            PyErr_SetString(PyExc_TypeError,
                            "data sent to trianglemodule error:List size of attributes is different from vertex to vertex.");
            return NULL;
          }
          for(i = 0; i < in.numberofpointattributes; i++){
            Attr = PyFloat_AsDouble(PyList_GetItem(Attrlist,i));
            in.pointattributelist[in.numberofpointattributes*j+i]= (REAL)Attr;
            /*   printf("i =%i\n",i);  */
            /*   printf("j =%i\n",j);  */
            /*   printf("in.pointattributelist[4*j+i]
                 =%f\n",in.pointattributelist[4*j+i]); */
          }
        }
      } 
    }
  }
    
     
  /* this half from triangulate*/
  /* set up the switch arguments to the triangulation routine */

  mod = PyString_AS_STRING(mode);
     
         
  out.pointlist = (REAL *)NULL;
  out.pointmarkerlist = (int *)NULL;
  out.numberofpointattributes = in.numberofpointattributes;
  out.pointattributelist = (REAL *)NULL;
  
  out.trianglelist = (int *)NULL;
  out.triangleattributelist = (REAL *)NULL;                   
  out.trianglearealist = (REAL *)NULL;                        
  out.neighborlist = (int *)NULL;
     
  out.segmentlist = (int *)NULL;
  out.segmentmarkerlist = (int *)NULL;
     
  out.edgelist = (int *)NULL;
  out.edgemarkerlist = (int *)NULL;
     
  out.holelist = (REAL *)NULL;
  out.regionlist = (REAL *)NULL;
    
  /*printf("\n\nTriangulate input args: %s \n\n", mod); */
  triangulate(mod, &in, &out, (struct triangulateio *)NULL );

  /*
    ------- Pass point numbers,coordinates and neighbors back to Python ------
    we send back a dictionary:                                               
    { index : [ coordinates, [connections], Attribute ] } 
  */
  holder = PyDict_New();
     
  /* Add pointlist */
  listsize = out.numberofpoints;
  holderlist = PyList_New(listsize);
     
  for(i=0; i<listsize;i++){
    PyObject *mlist = Py_BuildValue((char *)"(d,d)", 
                                    out.pointlist[i*2  ], out.pointlist[i*2+1]);  
    PyList_SetItem(holderlist,i, mlist);
  }  
  ii=PyString_FromString("generatedpointlist");
  PyDict_SetItem(holder, ii, holderlist); Py_DECREF(ii); Py_DECREF(holderlist);
    
  /* Add point marker list */
  listsize = out.numberofpoints;
  holderlist = PyList_New(listsize);
  
  for(i=0; i<listsize;i++){
    PyObject *mlist = Py_BuildValue((char *)"d", 
                                    out.pointmarkerlist[i]);     
    PyList_SetItem(holderlist,i, mlist); 
  }  
  ii=PyString_FromString("generatedpointmarkerlist");
  PyDict_SetItem(holder, ii, holderlist); Py_DECREF(ii); Py_DECREF(holderlist);
    
  /* Add point attribute list */
  listsize = out.numberofpoints;
  holderlist = PyList_New(listsize);
  
  for(i=0; i<listsize;i++){
    attsize = out.numberofpointattributes;
    attributelist = PyList_New(attsize);
    for(iatt=0; iatt<attsize;iatt++){
      PyObject *mlist = Py_BuildValue((char *)"d", 
                                      out.pointattributelist[i*attsize + iatt]);     
      PyList_SetItem(attributelist,iatt, mlist);
    }      
    PyList_SetItem(holderlist,i, attributelist);
  }  
  ii=PyString_FromString("generatedpointattributelist");
  PyDict_SetItem(holder, ii, holderlist); Py_DECREF(ii); Py_DECREF(holderlist);  
  
  /* Add triangle list */
  listsize = out.numberoftriangles;
  holderlist = PyList_New(listsize);
  for(i=0; i<listsize;i++){
    PyObject *mlist = Py_BuildValue((char *)"(i,i,i)", 
                                    out.trianglelist[i*3  ], out.trianglelist [i*3+1], out.trianglelist [i*3+2]);    
    PyList_SetItem(holderlist,i, mlist);
  }    
  ii=PyString_FromString("generatedtrianglelist");
  PyDict_SetItem(holder, ii, holderlist); Py_DECREF(ii); Py_DECREF(holderlist);
     
     
  /* Add triangle attribute list */
  listsize = out.numberoftriangles;
  holderlist = PyList_New(listsize);
     
  for(i=0; i<listsize; i++){
    attsize = out.numberoftriangleattributes;
    attributelist = PyList_New(attsize);       
    for(iatt=0; iatt<attsize;iatt++){
      PyObject *mlist = Py_BuildValue((char *)"d",out.triangleattributelist[i*attsize + iatt]);     
      PyList_SetItem(attributelist,iatt, mlist);
    }      
    PyList_SetItem(holderlist,i, attributelist);
  }  
  ii=PyString_FromString("generatedtriangleattributelist");
  PyDict_SetItem(holder, ii, holderlist); Py_DECREF(ii); Py_DECREF(holderlist);
  
  /* Add segment list */
  listsize = out.numberofsegments;
  holderlist = PyList_New(listsize);
  for(i=0; i<listsize;i++){
    PyObject *mlist = Py_BuildValue((char *)"(i,i)", 
                                    out.segmentlist[i*2  ],
                                    out.segmentlist [i*2+1]);
    PyList_SetItem(holderlist,i, mlist);
  }    
  ii=PyString_FromString("generatedsegmentlist");
  PyDict_SetItem(holder, ii, holderlist); Py_DECREF(ii); Py_DECREF(holderlist);  
  
  /* Add segment marker list */
  listsize = out.numberofsegments;
  holderlist = PyList_New(listsize);
  for(i=0; i<listsize;i++){
    PyObject *mlist = Py_BuildValue((char *)"i", 
                                    out.segmentmarkerlist[i]);
    PyList_SetItem(holderlist,i, mlist);
  }    
  ii=PyString_FromString("generatedsegmentmarkerlist");
  PyDict_SetItem(holder, ii, holderlist); Py_DECREF(ii); Py_DECREF(holderlist);  
  /* Add triangle neighbor list */
  if (out.neighborlist != NULL) {
    listsize = out.numberoftriangles;
    holderlist = PyList_New(listsize);
    for(i=0; i<listsize;i++){
      PyObject *mlist = Py_BuildValue((char *)"(i,i,i)", 
                                      out.neighborlist[i*3  ],
                                      out.neighborlist [i*3+1],
                                      out.neighborlist [i*3+2]);    
      PyList_SetItem(holderlist,i, mlist);
    }    
    ii=PyString_FromString("generatedtriangleneighborlist");
    PyDict_SetItem(holder, ii, holderlist);
    Py_DECREF(ii); Py_DECREF(holderlist);
  }   
     
  /* Free in/out structure memory */
  
  /* OUT */

  if(!out.pointlist){
    free(out.pointlist);  out.pointlist=NULL;
  }
  if(!out.pointmarkerlist){    
    free(out.pointmarkerlist); out.pointmarkerlist=NULL;
  }
  if(!out.pointattributelist){    
    free(out.pointattributelist); out.pointattributelist=NULL;
  }
    
 
  if(!out.trianglelist){    
    free(out.trianglelist); out.trianglelist=NULL;
  }
  if(!out.triangleattributelist){    
    free(out.triangleattributelist); out.triangleattributelist=NULL;
  }
  if(!out.trianglearealist){    
    free(out.trianglearealist); out.trianglearealist=NULL;
  }
  if(!out.neighborlist){    
    free(out.neighborlist); out.neighborlist=NULL;
  }
  if(!out.segmentlist){
    free(out.segmentlist); out.segmentlist =NULL;
  }
  if(!out.segmentmarkerlist){
    free(out.segmentmarkerlist); out.segmentmarkerlist  =NULL;
  }
  if(!out.edgelist){
    free(out.edgelist);  out.edgelist=NULL;
  }
  if(!out.edgemarkerlist){
    free(out.edgemarkerlist);  out.edgemarkerlist=NULL;
  }
  if(!out.holelist){
    free(out.holelist); out.holelist=NULL;
  }
  if(!out.regionlist){
    free(out.regionlist); out.regionlist=NULL;
  }
    
  /*  IN */
  
  if(!in.pointlist){
    free(in.pointlist);  in.pointlist   =NULL;             
  }
  if(!in.pointattributelist){
    free(in.pointattributelist); in.pointattributelist =NULL;       
  }
  if(!in.pointmarkerlist){
    free(in.pointmarkerlist); in.pointmarkerlist    =NULL;        
  }
  if(!in.segmentlist){
    free(in.segmentlist);  in.segmentlist    =NULL;         
  }
  if(!in.segmentmarkerlist){
    free(in.segmentmarkerlist); in.segmentmarkerlist    =NULL;   
  }
  if(!in.regionlist){
    free(in.regionlist); in.regionlist  =NULL;            
  }
  if(!in.holelist){
    free(in.holelist); in.holelist=NULL;
  }

  //return Py_BuildValue((char *)"O", holder);
  return Py_BuildValue((char *)"O", holder);
}

/* end of my function*/


   
    
static PyMethodDef triang_methods[] = {
  {(char *)"genMesh", triang_genMesh, 1, (char *)"Passes hull points to triangle.All arguments are lists.(<hull>,<seglist>,<holelist>,<regionlist>)-><hull>"}, 
  {NULL,NULL}
};

void inittriang(){
  Py_InitModule((char *)"triang",triang_methods);
}