checks to see if ring r is an outer ring of shape */
| 219 | |
| 220 | /* checks to see if ring r is an outer ring of shape */ |
| 221 | int msIsOuterRing(shapeObj *shape, int r) |
| 222 | { |
| 223 | int i, status=MS_TRUE; |
| 224 | int result1, result2; |
| 225 | |
| 226 | if(shape->numlines == 1) return(MS_TRUE); |
| 227 | |
| 228 | for(i=0; i<shape->numlines; i++) { |
| 229 | if(i == r) continue; |
| 230 | |
| 231 | /* |
| 232 | ** We have to test 2, or perhaps 3 points on the shape against the ring because |
| 233 | ** it is possible that at most one point could touch the ring and the function |
| 234 | ** msPointInPolygon() is indeterminite in that case. (bug #2434) |
| 235 | */ |
| 236 | result1 = msPointInPolygon(&(shape->line[r].point[0]), &(shape->line[i])); |
| 237 | result2 = msPointInPolygon(&(shape->line[r].point[1]), &(shape->line[i])); |
| 238 | if(result1 == result2) { /* same result twice, neither point was on the edge */ |
| 239 | if(result1 == MS_TRUE) status = !status; |
| 240 | } else { /* one of the first 2 points were on the edge of the ring, the next one isn't */ |
| 241 | if(msPointInPolygon(&(shape->line[r].point[2]), &(shape->line[i])) == MS_TRUE) |
| 242 | status = !status; |
| 243 | } |
| 244 | |
| 245 | } |
| 246 | |
| 247 | return(status); |
| 248 | } |
| 249 | |
| 250 | /* |
| 251 | ** Returns a list of outer rings for shape (the list has one entry for each ring, |
no test coverage detected