GM_CreateBufferArea |
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 GM_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.
SyntaxGM_Error_t32 __stdcall GM_CreateBufferArea ( GM_LayerHandle_t32 aFeatureLayer, // IN: Layer the feature is in GM_FeatureClassType_t8 aFeatureClassType, // IN: Type of feature class (area, point, line) uint32 aFeatureIndex, // IN: Index of feature in layer double aBufferDistance, // IN: Distance in meters of buffer to create (use negative values to create a buffer inside an area feature) GM_LayerHandle_t32 aBufferLayer // IN: Layer to add new buffer area(s) to );