VF-BlenderSegmentMesh

This add-on was designed for Blender version 2.8-4.1 (though not all previous versions may be fully supported). For Blender 4.2 and onwards, please see the new Mesh Kit extension.

Divides a mesh (such as OpenStreetMap 3D meshes) into XY grid segments for more efficient view culling in realtime rendering engines like Unity, Unreal Engine, and Godot.

Installation and Usage

• Download VF_segmentMesh.py
• Open Blender Preferences and navigate to the "Add-ons" tab
• Install and enable the add-on
• It will show up in the 3D view VF Tools tab
• Select a single mesh object to segment
  • WARNING: segmenting large meshes can take a long time (measured in minutes, not seconds!)

Settings

• Size Sets the X and Y dimensions of a single tile
• Count Sets the number of tiles in X and Y
• Include Determines handling of geometry located outside of the total tiled area (tile size × tile count)
  • Only Inside - Limits each tile to just the elements that fall within the boundaries of that tile
  • Extend Edges - Includes geometry outside the boundaries of the total area in the nearest edge tile
• Segment The type of geometry location used to segment meshes between tiles
  • Per Polygon - Divides meshes at the polygon level using the average vertex position
    • This is particularly helpful for large objects that span multiple tiles (which would otherwise defeat the purpose of viewpoint culling)
  • Island Average - Iterates over every polygon to find connected mesh islands and uses the average vertex locations to determine if the group falls within the tile boundary
  • Island Weighted - Iterates over every polygon to find connected mesh islands and uses the average of weighted polygon locations to determine if the group falls within the tile boundary
• Origin Sets the origin type for the final tile objects
  • Tile - The centre point of each tile range
    • This can be ideal for predictable tile placement, but if the segmented geometry is entirely in one corner, may not be suitable for transparency sorting in some situations
  • Bounding Box - The bounding box of the segmented geometry
  • Median - The median point of the segmented geometry positions
  • Mass - The mass of the segmented geometry
  • Volume - The volume of the segmented geometry
• Preview creates a temporary mesh object to show the resulting grid based on the tile size and count

Notes

• Geometry Nodes are used to store island location information as face attributes. Any other modifiers on the source mesh will not be applied during this process; the base mesh is what will be segmented, and any modifiers will still be present for each of the segments.
• This software is provided without guarantee of usability or safety, use at your own risk