Meshlets - Samples and tutorial
Posted: Thu Jul 31, 2025 10:14 pm
Meshlets
(available from version 2026.1 Alpha3 - 26.01)
References:
Octane 2026.1 Alpha 1: viewtopic.php?t=84311
2026.1 Alpha 3: viewtopic.php?t=84831
"This feature allows Octane to render very detailed geometry while not using a lot of device memory. It works similar to "Nanite" in Unreal Engine by adaptively choosing a not too fine and not too coarse level of detail for different parts of a mesh - depending on what is visible in the render.
In its current form it needs to be enabled explicitly in the geometry preferences as it requires a fairly expensive preprocessing step. During the preprocessing, Octane clusters a mesh into "meshlets" and then reduces the amount of geometry iteratively into multiple levels of detail. The preprocessed data is stored in a cache file in the OctaneRender cache directory to avoid having to redo the preprocessing every time the mesh is used.
During rendering, Octane chooses a selection of "meshlets" that results in a watertight mesh while making sure that the triangles are not too small or too large in image space and compared to the pixel size. This automatically limits the amount of data that is actually loaded into VRAM without showing a visible difference to the original high resolution geometry. Since Octane needs to render the scene to determine the meshlet selection, we introduced the concept of a "settling phase" where Octane determines a fitting meshlet and virtual texture selection by iteratively rendering the current scene, and only starts progressive rendering after meshlets and virtual textures (see below) have settled.
This feature is very well suited for 3D scans and/or vertex displaced, subdivided geometry."
Meshlets in 3dsMax plugin:
Meshlet can be enabled by adding an Octane Geometry Properties modifier, and checking the 'Convert to Meshlets' box in the Misc rollup:
Enter a unique string as Meshet ID, to ensure that Octane engine can load the correct cache file.
The object also need to be set as a Movable proxy (Octane object properties).
Meshlet cache size:
Use Octane Preferences: Material tab:
Select the size with the parameter 'Meshlet cache size (GB)'
Meshlet cache location:
Use Octane Preferences: menu Tools/Explore Octane Virtual textures cache Folder to open Windows explorer.
This should be a folder like C:\Users\xxxxx\AppData\Local\OctaneRender\cache\vtex
You can delete those cache files, but you may need to close 3dsMax when files have been used.
Note: While rendering, you should notice that the first few frames are rendered with a lower resolution mesh.
'LOD selection bias' has been added to influence the LOD data selection. (Render settings, Kernel tab, render Kernel rollup (eg Direct Light))
Decreasing its value, will make the loaded LOD data cruder, increasing its value will make the loaded LOD data finer. The default is 0.
Here are some results with values 0, -5, -8
Sample:
meshlet_Sample01_King_mx18.max
(available from version 2026.1 Alpha3 - 26.01)
References:
Octane 2026.1 Alpha 1: viewtopic.php?t=84311
2026.1 Alpha 3: viewtopic.php?t=84831
"This feature allows Octane to render very detailed geometry while not using a lot of device memory. It works similar to "Nanite" in Unreal Engine by adaptively choosing a not too fine and not too coarse level of detail for different parts of a mesh - depending on what is visible in the render.
In its current form it needs to be enabled explicitly in the geometry preferences as it requires a fairly expensive preprocessing step. During the preprocessing, Octane clusters a mesh into "meshlets" and then reduces the amount of geometry iteratively into multiple levels of detail. The preprocessed data is stored in a cache file in the OctaneRender cache directory to avoid having to redo the preprocessing every time the mesh is used.
During rendering, Octane chooses a selection of "meshlets" that results in a watertight mesh while making sure that the triangles are not too small or too large in image space and compared to the pixel size. This automatically limits the amount of data that is actually loaded into VRAM without showing a visible difference to the original high resolution geometry. Since Octane needs to render the scene to determine the meshlet selection, we introduced the concept of a "settling phase" where Octane determines a fitting meshlet and virtual texture selection by iteratively rendering the current scene, and only starts progressive rendering after meshlets and virtual textures (see below) have settled.
This feature is very well suited for 3D scans and/or vertex displaced, subdivided geometry."
Meshlets in 3dsMax plugin:
Meshlet can be enabled by adding an Octane Geometry Properties modifier, and checking the 'Convert to Meshlets' box in the Misc rollup:
Enter a unique string as Meshet ID, to ensure that Octane engine can load the correct cache file.
The object also need to be set as a Movable proxy (Octane object properties).
Meshlet cache size:
Use Octane Preferences: Material tab:
Select the size with the parameter 'Meshlet cache size (GB)'
Meshlet cache location:
Use Octane Preferences: menu Tools/Explore Octane Virtual textures cache Folder to open Windows explorer.
This should be a folder like C:\Users\xxxxx\AppData\Local\OctaneRender\cache\vtex
You can delete those cache files, but you may need to close 3dsMax when files have been used.
Note: While rendering, you should notice that the first few frames are rendered with a lower resolution mesh.
'LOD selection bias' has been added to influence the LOD data selection. (Render settings, Kernel tab, render Kernel rollup (eg Direct Light))
Decreasing its value, will make the loaded LOD data cruder, increasing its value will make the loaded LOD data finer. The default is 0.
Here are some results with values 0, -5, -8
Sample:
meshlet_Sample01_King_mx18.max