<p>This would not be perfect but should probably work well enough for your use case - you could render the objects from lots of different angles with a different solid color for each mesh component (without lighting) then remove any meshes that didn't appear in the final image by counting the pixel colours.
If the objects aren't split up into separate meshes then do this by repeatedly merging groups of triangles which share a vertex into the same group, starting with one group per triangle or polygon.</p>

CC BY-SA 4.0
2018-05-14T20:10:18.150Z
It does work. ive used this in a job nack in 2000 for removing extra geometry of cad models.
joojaa
CC BY-SA 3.0
2018-04-14T10:23:22.133Z
2018-04-14T10:23:22.133Z
Graham
<p>I have an .OBJ 3D model with many complex meshes shape.</p>

<p>The meshes are complex because each of them have multiple internal mesh located in it.</p>

<p>Meshes with internal geometry is defined as a mesh, which consists of many nested geometry.
For example: a tank in .OBJ file is represented by 1 outer geometry with several nested small geometry in it. Total number of geometry to represent that tank would be 5-7.</p>

<p>I want to simplify the tank mesh object above to be represented by 1 geometry instead of multiple geometries.</p>

<p>What tool and what programming language can I use to iterate all the meshes object, remove all internal geometry in .OBJ file?</p>

<p>Please ask if you need clarification.</p>

<p>Thank you.</p>

CC BY-SA 3.0
2018-04-10T18:28:02.083Z
Hi, can you clarify what you want to do—merge the 5–7 geometries down to 1, keeping all the verts and faces from all of them? Or do you mean the tank has modeled interior spaces like the cabin, seats, controls etc and you want to remove these, keeping only the exterior surface?
Nathan Reed
CC BY-SA 3.0
2018-04-10T21:39:26.803Z
I want to remove interior spaces. There are some interior item overlapping/intersecting with the exterior surface; for those items, I want to do boolean union to merge them.
user2150279
CC BY-SA 3.0
2018-04-10T22:10:43.243Z
Look into csg (constructive solid geometry) for the boolean operations you are looking for. Most 3d programs have them (Mesh lab, Maya, etc)
Andrew Wilson
<3d><mesh>
How to remove internal geometry programmatically in all meshes in .OBJ file?
user2150279
# How to remove internal geometry programmatically in all meshes in .OBJ file?

(Asked by: username_0 on 2018-04-10)

I have an .OBJ 3D model with many complex meshes shape.

The meshes are complex because each of them have multiple internal mesh located in it.

Meshes with internal geometry is defined as a mesh, which consists of many nested geometry.
For example: a tank in .OBJ file is represented by 1 outer geometry with several nested small geometry in it. Total number of geometry to represent that tank would be 5-7.

I want to simplify the tank mesh object above to be represented by 1 geometry instead of multiple geometries.

What tool and what programming language can I use to iterate all the meshes object, remove all internal geometry in .OBJ file?

Please ask if you need clarification.

Thank you.

**Tags:** 3d, mesh

> **Comments:**
> **username_1**: Hi, can you clarify what you want to do—merge the 5–7 geometries down to 1, keeping all the verts and faces from all of them? Or do you mean the tank has modeled interior spaces like the cabin, seats, controls etc and you want to remove these, keeping only the exterior surface?  
> **username_0**: I want to remove interior spaces. There are some interior item overlapping/intersecting with the exterior surface; for those items, I want to do boolean union to merge them.  
> **username_2**: Look into csg (constructive solid geometry) for the boolean operations you are looking for. Most 3d programs have them (Mesh lab, Maya, etc)  

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## 1 answers

### Answer by username_3 on 2018-04-14. Score: 1

This would not be perfect but should probably work well enough for your use case - you could render the objects from lots of different angles with a different solid color for each mesh component (without lighting) then remove any meshes that didn't appear in the final image by counting the pixel colours.
If the objects aren't split up into separate meshes then do this by repeatedly merging groups of triangles which share a vertex into the same group, starting with one group per triangle or polygon.

> **Comments:**
> **username_4**: It does work. ive used this in a job nack in 2000 for removing extra geometry of cad models.  

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