Collections allow batch rendering of object of the same type:
Points Line segments Polylines (paths) Raw Triangles Polygons
Points
Line segments
Polylines (paths)
Raw Triangles
Polygons
Each collection has several modes:
raw (point, segment, path, triangle, polygon) agg (point, segment, path, polygon) agg+ (path, polygon)
raw (point, segment, path, triangle, polygon)
agg (point, segment, path, polygon)
agg+ (path, polygon)
the case on all graphic cards. This means such shared attributes must be normalized on CPU and scales back on GPU (in shader code).