Pixel quadtrees and voxel octrees.
Store any type in an OctreeI32
, OctreeU32
, QuadtreeI32
,
or QuadtreeU32
, all of which are specific instances of the generic Tree
. A
Tree
represents a map from (Level, Integer Coordinates)
to T
. Thus it is useful for storing pixel or
voxel data with level-of-detail. The tree also requires that if a node slot is occupied (has data), then all ancestor slots
are also filled.
This structure is optimized for iteration speed and spatial queries that benefit from a bounding volume hierarchy (like
raycasting). Finding a single node by NodeKey
starting from the root should be minimized as much as
possible, so you might find it useful to cache NodePtr
s or amortize the search with a full tree
traversal. Memory usage is decent given the simplicity of the implementation, and the pointer overhead is easily amortized
by using dense chunk values.
- random access with
NodeKey
: O(depth) - random access with
NodePtr
: O(1) - iteration: O(nodes)
- memory usage per node:
- level 0:
size_of::<T>()
bytes - level N > 0:
size_of::<T>() + CHILDREN * 4
bytes - where
CHILDREN=4
for a quadtree andCHILDREN=8
for an octree
- level 0:
License: MIT OR Apache-2.0