Home / Forums / Writing an Octree in C++ for Fast 3D Spatial Partitioning and Entity Queries

UnreliableCode Community

Developer Research, Reverse Engineering & Coding Community

Tutorial

Writing an Octree in C++ for Fast 3D Spatial Partitioning and Entity Queries

MatrixRecon
3D Math & Vectors
MEMBER
Rep: 225
Join Date: Jan 2025
Posts: 33
Thanks: 55
4y ago · Jan 4, 2022 4:42 PM
#1
Hierarchical 3D spatial partitioning using Octrees reduces entity proximity checks from O(N^2) down to O(N log N).
MatrixRecon · 3D Mathematics & View Matrix Calculations
The following users thanked MatrixRecon for this post:
DirectXRay
DirectX 12 / Vulkan Dev
MEMBER
Rep: 240
Join Date: Feb 2023
Posts: 31
Thanks: 60
4y ago · Jan 4, 2022 6:01 PM
#2
Only subdividing nodes when entity count exceeds a threshold (e.g. 8 objects) keeps memory depth optimal.
DirectXRay · DirectX 12 & Vulkan Command Lists
RenderMaster
ImGui UI Designer
VIP
Rep: 310
Join Date: Sep 2023
Posts: 32
Thanks: 82
4y ago · Jan 5, 2022 12:01 AM
#3
Frustum-octree intersection allows skipping entire bounding box branches that are outside the camera view.
RenderMaster | Clean UI Design & Dear ImGui widgets