askChangeZoomlevel abstract method
Called when the map zoom level changes.
This method provides an opportunity to:
- Load markers appropriate for the new zoom level
- Apply zoom-based filtering or clustering
- Update marker styles or visibility
- Initialize data structures for the new view
The method is called before askChangeBoundingBox when both zoom level and position change simultaneously.
zoomlevel
The new zoom level (typically 0-20)
boundingBox
The visible geographic area at the new zoom level
projection
The pixel projection for coordinate transformations
Implementation Notes:
- This is the primary method for zoom-aware marker management
- Consider marker clustering at lower zoom levels
- Filter out inappropriate markers for the zoom level
- Call requestRepaint if markers change
Implementation
void askChangeZoomlevel(int zoomlevel, BoundingBox boundingBox, PixelProjection projection);