globalmapper.CreateBufferArea
=============================

.. currentmodule:: globalmapper

.. py:function:: CreateBufferArea(GM_LayerHandle_t32 aFeatureLayer, GM_FeatureClassType_t8 aFeatureClassType, uint32 aFeatureIndex, float aBufferDistance, GM_LayerHandle_t32 aBufferLayer) -> GM_Error_t32

    Create a buffer area some distance around the specified feature. The parameters specify the existing feature (this
    can be a point, line, or area feature) that you want to create a buffer around as well as the buffer distance to
    use. If you want to create a buffer inside an area boundary, use a negative buffer distance. The newly created
    buffer area(s) will be added to the layer *aBufferLayer*.

    You can use :doc:`CreateCustomVectorLayer<globalmapper.CreateCustomVectorLayer>` if you want to add
    these to a new layer. The new buffer areas will be added to the end of the area list for *aBufferLayer*, so you can
    use the mNumAreas value in the GM_LayerInfo_t structure for that layer before and after the call to determine how
    many buffer areas were added and the indices used.

    :param GM_LayerHandle_t32 aFeatureLayer: Layer the feature is in
    :param GM_FeatureClassType_t8 aFeatureClassType: Type of feature class (area, point, line)
    :param uint32 aFeatureIndex: Index of feature in layer
    :param float aBufferDistance: Distance in meters of buffer to create (use negative values to create a buffer inside an area feature)
    :param GM_LayerHandle_t32 aBufferLayer: Layer to add new buffer area(s) to
    :returns: Error Code
    :rtype: GM_Error_t32