Geometry Nodes: Duplicate Elements Node

This adds a node which copies part of a geometry a dynamic number
of times.

Different parts of the geometry can be copied differing amounts
of times, controlled by the amount input field. Geometry can also
be ignored by use of the selection input.

The output geometry contains only the copies created by the node.
if the amount input is set to zero, the output geometry will be
empty. The duplicate index output is an integer index with the copy
number of each duplicate.

Differential Revision: https://developer.blender.org/D13701

source/blender/nodes/NOD_geometry.h

@@ -82,6 +82,7 @@ void register_node_type_geo_curve_to_mesh(void);
 void register_node_type_geo_curve_to_points(void);
 void register_node_type_geo_curve_trim(void);
 void register_node_type_geo_delete_geometry(void);
+void register_node_type_geo_duplicate_elements(void);
 void register_node_type_geo_distribute_points_on_faces(void);
 void register_node_type_geo_dual_mesh(void);
 void register_node_type_geo_edge_split(void);