topic Re: Convert Polygon/Polyline shapebuffer in File Geodatabase API Questions

Convert Polygon/Polyline shapebuffer

teamIgal — Mon, 13 May 2013 12:18:54 GMT

Hello,

I want to insert new Polygon in the feature class in the GDB.
So i am trying to insert it using SetGeometry, which can recieve only ShapeBuffer.

Is there a proper way to convert Polygon to shapebuffer?

Thanks,
Team Igal

Re: Convert Polygon/Polyline shapebuffer

VinceAngelo — Thu, 16 May 2013 13:45:42 GMT

ShapeBuffer.cpp in the samples/ShapeBuffer directory of the API seems to provide
an example of what's necessary. You can roll your own helper functions, but either
way, it's probably wise to review the shapefile reference PDFs in the doc directory.

- V

Re: Convert Polygon/Polyline shapebuffer

teamIgal — Sun, 26 May 2013 05:18:29 GMT

Hello,

i saw the samples in the ShapeBuffer.cpp, but it's not quite what i am looking for.
Can you please provide some code example to a transform between runtime objects, such as polyline to shapebuffer?

Thanks,
Team Igal

Re: Convert Polygon/Polyline shapebuffer

VinceAngelo — Sun, 26 May 2013 17:34:30 GMT

Between LineGeomTest and LineZGeomTest, it looks like the bases are covered --
conversion in both directions, with multiple dimensions -- what more do you need?

Perhaps it will help if you think of it as a "packing" exercise, instead of transformation.

- V

Re: Convert Polygon/Polyline shapebuffer

DavidSousa — Thu, 30 May 2013 22:13:15 GMT

It is not necessary to convert your PolyLine shape buffer to a ShapeBuffer because it already is one.

ShapeBuffer is the base class for all of the other shape buffer types. Since SetGeometry accepts a ShapeBuffer object, that means you can pass an instance of the base class or any of the derived classes. This is a fundamental object oriented programming technique of C++.

Here is a small extract from the ShapeBuffer sample program:

    MultiPartShapeBuffer lineGeometry;
    row.GetGeometry(lineGeometry);

    int numPts;
    lineGeometry.GetNumPoints(numPts);

Please note that lineGeometry is declared as a MultiPartShapeBuffer, and that we are able to pass it to GetGeometry with no problem.