globalmapper.CalcViewShed
=========================

.. currentmodule:: globalmapper

.. py:function:: CalcViewShed(GM_LayerHandle_t32 aLayer, GM_ViewShedParams_t aViewShedParms) -> GM_Error_t32, GM_LayerHandle_t32

    Performs a view-shed analysis on loaded elevation data and creates a new Viewshed layer with the results.
    The returned layer handle must be closed with :doc:`CloseLayer<../load/globalmapper.CloseLayer>` when you are done
    with it.

    :param GM_LayerHandle_t32 aLayer: Layer to get elevations from or gm.NULL for topmost layer at each point
    :param GM_ViewShedParams_t aViewshedParms: Parameters for creating Viewshed
    :returns: Error Code
    :rtype: GM_Error_t32
    :returns: Created Viewshed layer
    :rtype: GM_LayerHandle_t32