sungard-labs / mkpolygon-gpc Goto Github PK

Not sure if I was just unlucky, or if this fix is 100% but seems to solve my probs:
I added the 'if' statement after the assert in (MKPolygon *) polygonWithGPCPolygon:(gpc_polygon *) gpcPolygon interiorPolygons:(NSArray *)interiorPolygons , like so

NSAssert( gpcPolygon != NULL, @"attempt to create path from NULL gpcPolygon");

if (gpcPolygon->contour == NULL) {
    return nil;
}

The methods will only return the first polygon when there are multiple polygons resulted from the operation. I have done a modify of the codes to make it returns all the resulted polygons. Files in attachment.

MKPolygon+GPC.zip

Thanks for this lib, unfortunately it didn't fulfil all my requirements. I was performing the union of rectangles in a circle, when I added the last rectangle to close the circle I was expecting a polygon with the interior cut out. This library just enveloped the entire circle. Is there another method in gpc that could solve this case? Thanks

Hi,
Excellent code!! Really appreciate it!
I found one issue: I have two overlapping rings. Applying the operator intersection should result in 2 polygons. The code is however providing one polygon with a connecting branch. Do you see a way to distinguish multiple polygons resulting from the boolean operators?
Thanks