Actual source code: inpututils.c

  1: /* $Id: inpututils.c,v 1.19 2001/08/07 21:31:52 bsmith Exp $ */

  3: /*
  4:        Utilities for inputing, creating and managing simple two dimensional grids
  5: */

 7:  #include src/dm/ao/aoimpl.h
 8:  #include petscbt.h
 9:  #include petscdraw.h

 11: /*
 12:     cell_n        - number of cells
 13:     max_cell      - maximum space allocated for cell
 14:     cell_vertex   - vertices of each cell
 15:     cell_edge     - edges of the cell
 16:     cell_cell     - neighbors of cell
 17:     vertex_n      - number of vertices
 18:     vertex_max    - maximum space allocated for vertices
 19:     x,y           - vertex coordinates

 21:     xmin,ymin,xmax,ymax - bounding box of grid

 23:     edge_n        - total edges in the grid
 24:     edge_vertex   - vertex of all edges 
 25:     edge_max      - maximum space allocated for edge
 26:     edge_cell     - two neighbor cells who share edge

 28:     vertex_boundary - indicates for each vertex if it is a boundary

 30: */



 36: int AOData2dGridToAOData(AOData2dGrid agrid,AOData *ao)
 37: {
 38:   int        ierr;
 39:   int        *keys,nmax,i;
 40:   AOData     aodata;

 43:   /*
 44:       Create the database 
 45:   */
 46:   nmax = PetscMax(agrid->cell_n,agrid->vertex_n);
 47:   nmax = PetscMax(nmax,agrid->edge_n);
 48:   PetscMalloc(nmax*sizeof(int),&keys);
 49:   for (i=0; i<nmax; i++) {
 50:     keys[i] = i;
 51:   }
 52:   AODataCreateBasic(PETSC_COMM_WORLD,&aodata);
 53:     AODataKeyAdd(aodata,"cell",PETSC_DECIDE,agrid->cell_n);
 54:       AODataSegmentAdd(aodata,"cell","cell",4,agrid->cell_n,keys,agrid->cell_cell,PETSC_INT);
 55:       AODataSegmentAdd(aodata,"cell","vertex",4,agrid->cell_n,keys,agrid->cell_vertex,PETSC_INT);
 56:       AODataSegmentAdd(aodata,"cell","edge",4,agrid->cell_n,keys,agrid->cell_edge,PETSC_INT);
 57:     AODataKeyAdd(aodata,"edge",PETSC_DECIDE,agrid->edge_n);
 58:       AODataSegmentAdd(aodata,"edge","vertex",2,agrid->edge_n,keys,agrid->edge_vertex,PETSC_INT);
 59:       AODataSegmentAdd(aodata,"edge","cell",2,agrid->edge_n,keys,agrid->edge_cell,PETSC_INT);
 60:     AODataKeyAdd(aodata,"vertex",PETSC_DECIDE,agrid->vertex_n);
 61:       AODataSegmentAdd(aodata,"vertex","values",2,agrid->vertex_n,keys,agrid->vertex,PETSC_DOUBLE);
 62:       AODataSegmentAdd(aodata,"vertex","boundary",1,agrid->vertex_n,keys,agrid->vertex_boundary,PETSC_LOGICAL);
 63:   PetscFree(keys);
 64:   *ao = aodata;
 65:   return(0);
 66: }

 70: /*
 71:        User input the cell by drawing them one at a time
 72: */
 73: int AOData2dGridInput(AOData2dGrid agrid,PetscDraw draw)
 74: {
 75:   PetscDraw       popup;                           /* help window */
 76:   PetscDrawButton button;                          /* mouse button pressed */
 77:   int             cn, ierr,*cell;
 78:   PetscReal       *vertex,cx,cy;
 79:   char            title[120];

 82:   agrid->cell_max      = 500;
 83:   agrid->cell_n        = 0;
 84:   agrid->vertex_max    = 500;
 85:   agrid->vertex_n      = 0;
 86:   agrid->xmin          = PETSC_MAX;
 87:   agrid->xmax          = PETSC_MIN;
 88:   agrid->ymin          = PETSC_MAX;
 89:   agrid->ymax          = PETSC_MIN;

 91:   /*
 92:      Allocate large arrays to hold the nodes and cellrilateral lists 
 93:   */
 94:   PetscMalloc(2*agrid->vertex_max*sizeof(PetscReal),&agrid->vertex);
 95:   vertex = agrid->vertex;
 96:   PetscMalloc(4*agrid->cell_max*sizeof(int),&agrid->cell_vertex);
 97:   cell   = agrid->cell_vertex;


100:   /*
101:      Open help window and enter helpful messages
102:   */
103:   PetscDrawGetPopup(draw,&popup);
104:   PetscDrawString(popup,.1,.9,PETSC_DRAW_BLUE,"Use left button to\n   enter cell.");
105:   PetscDrawString(popup,.1,.7,PETSC_DRAW_BLUE,"Use center button to\n   end.");
106:   PetscDrawFlush(popup);

108:   PetscDrawGetMouseButton(draw,&button,&cx,&cy,PETSC_NULL,PETSC_NULL);
109:   AOData2dGridAddNode(agrid,cx,cy,&cn);
110:   cell[0] = cn;
111:   sprintf(title,"Input grid: Number vertex %d Number cell %d",agrid->vertex_n,agrid->cell_n);
112:   PetscDrawSetTitle(draw,title);
113:   while (button == BUTTON_LEFT) {
114:     /* wait for second vertex */
115:     PetscDrawGetMouseButton(draw,&button,&cx,&cy,PETSC_NULL,PETSC_NULL);
116:     if (button != BUTTON_LEFT) {
117:       SETERRQ(1,"Must press left button to complete cellrilateral");
118:     }
119:     AOData2dGridAddNode(agrid,cx,cy,&cn);
120:     cell[4*agrid->cell_n+1] = cn;
121:     PetscDrawLine(draw,vertex[2*cell[4*agrid->cell_n]],vertex[1+2*cell[4*agrid->cell_n]],
122:                          vertex[2*cell[4*agrid->cell_n+1]],vertex[1+2*cell[4*agrid->cell_n+1]],
123:                          PETSC_DRAW_RED);
124:     sprintf(title,"Input grid: Number vertex %d Number cell %d",agrid->vertex_n,agrid->cell_n);
125:     PetscDrawSetTitle(draw,title);
126:     /* wait for third vertex */
127:     PetscDrawGetMouseButton(draw,&button,&cx,&cy,PETSC_NULL,PETSC_NULL);
128:     if (button != BUTTON_LEFT) {
129:       SETERRQ(1,"Must press left button to complete cellrilateral");
130:     }
131:     AOData2dGridAddNode(agrid,cx,cy,&cn);
132:     cell[4*agrid->cell_n+2] = cn;
133:     PetscDrawLine(draw,vertex[2*cell[4*agrid->cell_n+1]],vertex[1+2*cell[4*agrid->cell_n+1]],
134:                          vertex[2*cell[4*agrid->cell_n+2]],vertex[1+2*cell[4*agrid->cell_n+2]],
135:                          PETSC_DRAW_RED);
136:     sprintf(title,"Input grid: Number vertex %d Number cell %d",agrid->vertex_n,agrid->cell_n);
137:     PetscDrawSetTitle(draw,title);
138:     /* wait for fourth vertex */
139:     PetscDrawGetMouseButton(draw,&button,&cx,&cy,PETSC_NULL,PETSC_NULL);
140:     if (button != BUTTON_LEFT) {
141:       SETERRQ(1,"Must press left button to complete cellrilateral");
142:     }
143:     AOData2dGridAddNode(agrid,cx,cy,&cn);
144:     cell[4*agrid->cell_n+3] = cn;
145:     PetscDrawLine(draw,vertex[2*cell[4*agrid->cell_n+2]],vertex[1+2*cell[4*agrid->cell_n+2]],
146:                          vertex[2*cell[4*agrid->cell_n+3]],vertex[1+2*cell[4*agrid->cell_n+3]],
147:                          PETSC_DRAW_RED);
148:     PetscDrawLine(draw,vertex[2*cell[4*agrid->cell_n]],vertex[1+2*cell[4*agrid->cell_n]],
149:                          vertex[2*cell[4*agrid->cell_n+3]],vertex[1+2*cell[4*agrid->cell_n+3]],
150:                          PETSC_DRAW_RED);
151:     agrid->cell_n++;
152:     sprintf(title,"Input grid: Number vertex %d Number cell %d",agrid->vertex_n,agrid->cell_n);
153:     PetscDrawSetTitle(draw,title);

155:     /* Get the first for the next cellralateral, or BUTTON_CENTER to end */
156:     PetscDrawGetMouseButton(draw,&button,&cx,&cy,PETSC_NULL,PETSC_NULL);
157:     if (button != BUTTON_LEFT) {break;}
158:     AOData2dGridAddNode(agrid,cx,cy,&cn);
159:     cell[4*agrid->cell_n] = cn;

161:     sprintf(title,"Input grid: Number vertex %d Number cell %d",agrid->vertex_n,agrid->cell_n);
162:     PetscDrawSetTitle(draw,title);
163:   }
164:   return(0);
165: }

169: /*
170:    Changes the node numbering for the cell to make sure they are all in 
171:    clockwise ordering
172: */
173: int AOData2dGridFlipCells(AOData2dGrid agrid)
174: {
175:   int       i,*cell = agrid->cell_vertex, cell_n = agrid->cell_n;
176:   PetscReal *vertex = agrid->vertex, sign;

179:   for (i=0; i<cell_n; i++) {
180:     /*
181:        compute the quantity

183:             x0      x1    x2      x3
184:             y0      y1    y2      y3
185:      */

187:      sign = vertex[2*cell[4*i]]*vertex[1+2*cell[4*i+1]]   + vertex[2*cell[4*i+1]]*vertex[1+2*cell[4*i+2]] +
188:             vertex[2*cell[4*i+2]]*vertex[1+2*cell[4*i+3]] + vertex[2*cell[4*i+3]]*vertex[1+2*cell[4*i]]   -
189:             vertex[1+2*cell[4*i]]*vertex[2*cell[4*i+1]]   - vertex[1+2*cell[4*i+1]]*vertex[2*cell[4*i+2]] -
190:             vertex[1+2*cell[4*i+2]]*vertex[2*cell[4*i+3]] - vertex[1+2*cell[4*i+3]]*vertex[2*cell[4*i]];

192:      if (sign == 0.0) {
193:        SETERRQ(1,"Bad cell");
194:      } else if (sign > 0) {
195:        int q1tmp = cell[4*i+1];
196:        cell[4*i+1] = cell[4*i+3];
197:        cell[4*i+3] = q1tmp;
198:      }
199:   }
200:   return(0);
201: }

205: /*
206:      AOData2dGridAddNode - Maintains a list of nodes given so far
207: */
208: int AOData2dGridAddNode(AOData2dGrid agrid, PetscReal cx, PetscReal cy, int *cn)
209: {
210:   int i;

213:   for (i=0; i<agrid->vertex_n; i++) {
214:     if ((PetscAbsReal(agrid->vertex[2*i] - cx) < 1.e-9) && (PetscAbsReal(agrid->vertex[1+2*i] - cy) < 1.e-9)) {
215:       *cn = i;
216:       return(0);
217:     }
218:   }
219:   agrid->vertex[2*agrid->vertex_n] = cx;
220:   agrid->vertex[1+2*agrid->vertex_n] = cy;
221:   *cn     = (agrid->vertex_n)++;

223:   if (cx < agrid->xmin)      agrid->xmin = cx;
224:   else if (cx > agrid->xmax) agrid->xmax = cx;
225:   if (cy < agrid->ymin)      agrid->ymin = cy;
226:   else if (cy > agrid->ymax) agrid->ymax = cy;
227:   return(0);
228: }

232: int AOData2dGridComputeNeighbors(AOData2dGrid agrid)
233: {
234:   int  i,j,*cell_edge,*edge_cell,*edge,*cell,*neighbors,e,ierr;

237:   agrid->edge_max = 2*agrid->vertex_n;
238:   agrid->edge_n   = 0;
239:   PetscMalloc(2*agrid->edge_max*sizeof(int),&agrid->edge_vertex);
240:   edge      = agrid->edge_vertex;
241:   PetscMalloc(4*agrid->cell_max*sizeof(int),agrid->cell_edge);
242:   cell_edge = agrid->cell_edge;
243:   PetscMalloc(2*agrid->edge_max*sizeof(int),&agrid->edge_cell);
244:   edge_cell = agrid->edge_cell;

246:   cell      = agrid->cell_vertex;

248:   /*
249:        Mark all neighbors (to start) with -1 to indicate missing neighbor
250:   */
251:   for (i=0; i<2*agrid->edge_max; i++) {
252:     edge_cell[i] = -1;
253:   }

255:   for (i=0; i<agrid->cell_n; i++) {
256:     for (j=0; j<agrid->edge_n; j++) {
257:       if (cell[4*i] == edge[2*j+1] && cell[4*i+1] == edge[2*j]) {
258:         cell_edge[4*i]   = j;
259:         edge_cell[2*j+1] = i;
260:         goto found0;
261:       }
262:     }
263:     /*
264:        Add a new edge to the list 
265:     */
266:     edge_cell[2*agrid->edge_n]   = i;
267:     edge[2*agrid->edge_n]        = cell[4*i];
268:     edge[2*agrid->edge_n+1]      = cell[4*i+1];
269:     cell_edge[4*i]                = agrid->edge_n;
270:     agrid->edge_n++;
271:     found0:;
272:     for (j=0; j<agrid->edge_n; j++) {
273:       if (cell[4*i+1] == edge[2*j+1] && cell[4*i+2] == edge[2*j]) {
274:         cell_edge[4*i+1] = j;
275:         edge_cell[2*j+1] = i;
276:         goto found1;
277:       }
278:     }
279:     /*
280:        Add a new edge to the list 
281:     */
282:     edge_cell[2*agrid->edge_n]   = i;
283:     edge[2*agrid->edge_n]        = cell[4*i+1];
284:     edge[2*agrid->edge_n+1]      = cell[4*i+2];
285:     cell_edge[4*i+1]              = agrid->edge_n;
286:     agrid->edge_n++;
287:     found1:;
288:     for (j=0; j<agrid->edge_n; j++) {
289:       if (cell[4*i+2] == edge[2*j+1] && cell[4*i+3] == edge[2*j]) {
290:         cell_edge[4*i+2] = j;
291:         edge_cell[2*j+1] = i;
292:         goto found2;
293:       }
294:     }
295:     /*
296:        Add a new edge to the list 
297:     */
298:     edge_cell[2*agrid->edge_n]   = i;
299:     edge[2*agrid->edge_n]        = cell[4*i+2];
300:     edge[2*agrid->edge_n+1]      = cell[4*i+3];
301:     cell_edge[4*i+2]              = agrid->edge_n;
302:     agrid->edge_n++;
303:     found2:;
304:     for (j=0; j<agrid->edge_n; j++) {
305:       if (cell[4*i+3] == edge[2*j+1] && cell[4*i] == edge[2*j]) {
306:         cell_edge[4*i+3] = j;
307:         edge_cell[2*j+1] = i;
308:         goto found3;
309:       }
310:     }
311:     /*
312:        Add a new edge to the list 
313:     */
314:     edge_cell[2*agrid->edge_n]   = i;
315:     edge[2*agrid->edge_n]        = cell[4*i+3];
316:     edge[2*agrid->edge_n+1]      = cell[4*i];
317:     cell_edge[4*i+3]              = agrid->edge_n;
318:     agrid->edge_n++;
319:     found3:;

321:   }

323:   PetscMalloc(4*agrid->cell_n*sizeof(int),&agrid->cell_cell);
324:   neighbors = agrid->cell_cell;
325:   for (i=0; i<agrid->cell_n; i++) {
326:     for (j=0; j<4; j++) {
327:       e = 2*agrid->cell_edge[4*i+j];

329:       /* get the edge neighbor that is not the current cell */
330:       if (i == agrid->edge_cell[e]) e++;
331:       neighbors[4*i+j] = agrid->edge_cell[e];
332:     }
333:   }

335:   return(0);
336: }

340: int AOData2dGridComputeVertexBoundary(AOData2dGrid agrid)
341: {
342:   int  i,j,*count,*cell_vertex = agrid->cell_vertex,ierr;

345:   /*
346:       allocate bitarray for boundary info
347:   */
348:   PetscBTCreate(agrid->vertex_n,agrid->vertex_boundary);

350:   /*
351:       count contains number of cell that contain the given vertex 
352:   */
353:   PetscMalloc(agrid->vertex_n*sizeof(int),&count);
354:   PetscMemzero(count,agrid->vertex_n*sizeof(int));

356:   for (i=0; i<agrid->cell_n; i++) {
357:     for (j=0; j<4; j++) {
358:       count[cell_vertex[4*i+j]]++;
359:     }
360:   }


363:   for (i=0; i<agrid->vertex_n; i++) {
364:     /* UGLY! Just for a quick solution: I want Dirichlet b.c. only at left edge! */
365:     PetscTruth neumann_bc;
366:     PetscOptionsHasName(PETSC_NULL,"-dirichlet_on_left",&neumann_bc);
367:     if (neumann_bc) {
368:       if ((count[i] < 4) && (agrid->vertex[2*i] == agrid->xmin)) {
369:         PetscBTSet(agrid->vertex_boundary,i);
370:       }
371:     } else {
372:       if (count[i] < 4) {
373:         PetscBTSet(agrid->vertex_boundary,i);
374:       }
375:     }
376:   }

378:   PetscFree(count);

380:   return(0);
381: }

385: /*
386:      Show the numbering of the vertex, cell and edge
387: */
388: int AOData2dGridDraw(AOData2dGrid agrid,PetscDraw draw)
389: {
390:   int       i, *cell = agrid->cell_vertex, *edge = agrid->edge_vertex,ierr;
391:   char      str[5];
392:   PetscReal *vertex = agrid->vertex,xx,yy,xmin,xmax,ymin,ymax,h,w;

395:   w = agrid->xmax - agrid->xmin;
396:   h = agrid->ymax - agrid->ymin;
397:   xmin = agrid->xmin - .1*w;
398:   xmax = agrid->xmax + .1*w;
399:   ymin = agrid->ymin - .1*h;
400:   ymax = agrid->ymax + .1*h;
401:   PetscDrawSetCoordinates(draw,xmin,ymin,xmax,ymax);

403:   /*
404:      Number the vertex
405:   */
406:   for (i=0; i<agrid->vertex_n; i++) {
407:     sprintf(str,"%d",i);
408:     PetscDrawString(draw,vertex[2*i],vertex[1+2*i],PETSC_DRAW_BLUE,str);
409:   }

411:   /*
412:      Number the cell
413:   */
414:   for (i=0; i<agrid->cell_n; i++) {
415:     sprintf(str,"%d",i);
416:     xx = .25*(vertex[2*cell[4*i]] + vertex[2*cell[4*i+1]] + vertex[2*cell[4*i+2]] + vertex[2*cell[4*i+3]]);
417:     yy = .25*(vertex[1+2*cell[4*i]] + vertex[1+2*cell[4*i+1]] + vertex[1+2*cell[4*i+2]] + vertex[1+2*cell[4*i+3]]);
418:     PetscDrawString(draw,xx,yy,PETSC_DRAW_GREEN,str);
419:   }

421:   /*
422:      Number the edge
423:   */
424:   for (i=0; i<agrid->edge_n; i++) {
425:     sprintf(str,"%d",i);
426:     xx = .5*(vertex[2*edge[2*i]] + vertex[2*edge[2*i+1]]);
427:     yy = .5*(vertex[1+2*edge[2*i]] + vertex[1+2*edge[2*i+1]]);
428:     PetscDrawLine(draw,vertex[2*edge[2*i]],vertex[1+2*edge[2*i]],vertex[2*edge[2*i+1]],vertex[1+2*edge[2*i+1]],PETSC_DRAW_BLACK);
429:     PetscDrawString(draw,xx,yy,PETSC_DRAW_VIOLET,str);
430:   }

432:   return(0);
433: }

437: /*
438:     Frees all the memory space allocated in AGrid
439: */
440: int AOData2dGridDestroy(AOData2dGrid agrid)
441: {

445:    PetscFree(agrid->vertex);
446:    PetscFree(agrid->cell_vertex);
447:    PetscFree(agrid->cell_edge);
448:    PetscFree(agrid->edge_vertex);
449:    PetscFree(agrid->edge_cell);
450:    PetscFree(agrid->cell_cell);
451:    PetscFree(agrid->vertex_boundary);
452:    PetscFree(agrid);
453:    return(0);
454: }

458: /*
459:     
460: */
461: int AOData2dGridCreate(AOData2dGrid *agrid)
462: {
465:   PetscNew(struct _p_AOData2dGrid,agrid);
466:   return(0);
467: }