[Gdal-dev] Changes between 1.1.9 and 1.20

[Clay, Bruce]

Frank:
When I used version 1.1.9 in my app I could read ArcView shape files
from the EP200 data set at http://www.cdc.gov/epiinfo/shape.htm.

When multiple polygons were used for a given country they were still
reported as type Polygon and everything was happy.  With the update to
version 1.2.0 the same data set reports them as multi-polygons and for
some reason they down parse out the same.  The code I used to use is:

	vectorNodePtr->type = POLYGON;

	status = OGRPolygonLabelPoint((OGRPolygon *)geom_handl,
&labelPoint);

	if (status >= 0) // == OGRERR_NONE)
		{
		status = 0;
		vectorNodePtr->labelPoint.xPos = labelPoint.getX();
		vectorNodePtr->labelPoint.yPos = labelPoint.getY();
		vectorNodePtr->labelPoint.zPos = labelPoint.getZ();
		}

	for( iRing = 0; iRing < geom_cnt; iRing++ )
		{
		ringPtr = new struct ringRec;
		if (ringPtr != NULL)
			{
			vectorNodePtr->ringList.push_back(ringPtr);

			OGRGeometryH ring_handl = OGR_G_GetGeometryRef(
geom_handl, iRing );

			if (dump_fdes != NULL)
				{
				fprintf(dump_fdes, "Ring %d\n", iRing );
				}

			// allocate memory for the current ring

			if (vectorNodePtr->numDimensions == 3)
				{
				ringPtr->threeDList = new std::vector
<struct threeDDataRec *>;

				ringPtr->twoDList = NULL;
				}
			else
				{
				ringPtr->twoDList = new std::vector
<struct twoDDataRec *>;

				ringPtr->threeDList = NULL;
				}

			for( iPoint = 0; iPoint <
OGR_G_GetPointCount(ring_handl); iPoint++ )
				{
				if (vectorNodePtr->numDimensions == 3)
					{
					threeDdataPtr = new struct
threeDDataRec;

	
ringPtr->threeDList->push_back(threeDdataPtr);

			// set default values for color and line width

					threeDdataPtr->colorIndex = 0;
					threeDdataPtr->lineWidth = 1.0f;

					threeDdataPtr->xPos =
OGR_G_GetX( ring_handl, iPoint);
					threeDdataPtr->yPos =
OGR_G_GetY( ring_handl, iPoint);
					threeDdataPtr->zPos =
OGR_G_GetZ( ring_handl, iPoint);
					if (dump_fdes != NULL)
						{
						fprintf(dump_fdes, "
%d: (%g,%g,%g)\n", iPoint,
	
OGR_G_GetX( ring_handl, iPoint ),
	
OGR_G_GetY( ring_handl, iPoint ),
	
OGR_G_GetZ( ring_handl, iPoint ) );
						}
					}
				else
					{
					twoDdataPtr = new struct
twoDDataRec;
	
ringPtr->twoDList->push_back(twoDdataPtr);

			// set default values for color and line width

					twoDdataPtr->colorIndex = 0;
					twoDdataPtr->lineWidth = 1.0f;

					twoDdataPtr->xPos = OGR_G_GetX(
ring_handl, iPoint);
					twoDdataPtr->yPos = OGR_G_GetY(
ring_handl, iPoint);
					if (dump_fdes != NULL)
						{
						fprintf(dump_fdes, "
%d: (%g,%g)\n", iPoint,
	
OGR_G_GetX( ring_handl, iPoint ),
	
OGR_G_GetY( ring_handl, iPoint ));
						}
					}
				}
			}  // if ringPtr != NULL
		}  // end of for ring = 0 to geom_cnt

I notice that OGR_G_GetPointCount returns 0 with the multipolygon so I
tried changing GetPointCount to (OGRMultiPolygon
*)ring_handl)->getNumGeometries().  That only returns a count of 1.
That is the only get count type of call I saw when I searched for
MultiPolygon.

Do you see anything I am missing?


Thanks for your time and the library.


Bruce Clay
bclay at ball.com