What is Octant size of Gridmap for?

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:bust_in_silhouette: Asked By volzhs
:warning: Old Version Published before Godot 3 was released.

There is Cell / Size and Cell / Octant size properties in Gridmap.
Cell size is changed when “Size” changed.
But I can’t see any visual difference with changing “Octant size” of Gridmap.
What is this property for?

Like quadrants on tilemaps, used by the engine to work with the group of cells in that zone.

I don’t know much detail of Godot but that use to be mostly for physics engines optimizations.

eons | 2016-12-14 13:34

:bust_in_silhouette: Reply From: Zylann

It has a similar meaning as the quadrant size of TileMap.
GridMap is structured in cubic chunks so they get culled and rendered together in a batch rather than drawing every single block one by one (I often compare this to the chunk size in Minecraft).

The size of octants is usually good enough, but you can tweak it if you need some performance tuning. For example if blocks are too big, then you could set a lower octant size. Or if cubes are small and numerous, octant size could be higher.