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C# fot JT files - Int32CDP arithmetic decoding




I'm writting a 3D player in C#, and i'm trying to add JT format to this application.


So far, i've been able to get the full product structure from JT files, but i'm encountering issues for Tri Strip Set Shape LOD Element. Here and there, i've to read Int32CDP compressed through arithmectic method. But now way for me to achieve it.


Could it be possible to get the sources from your C++ tool kit to convert it in C#? Or to get some help?






Re: C# fot JT files - Int32CDP arithmetic decoding

Siemens Legend Siemens Legend
Siemens Legend

Hi, we are not able to provide source but I would like to help you work from the spec. Can you provide specific details on the issues you are seeing? I assume you are working from the spec we post on

Mike Z

Re: C# fot JT files - Int32CDP arithmetic decoding


Well I have downloaded from your site documentation about JT versions 9 and 10, and trying to implement a decoder in C#.Net. I have achieved to do the tree structure, and now I'm trying with solids, but it's a bit hard now.

I am at the "Topologically Compressed Rep Data" level now, and arithmetic decompression algorithms are quite hard to implement. Could you help?

Now, my player is able to load 300Mo 3DXML in less than 80s and can display it at 10 FPS with full details...


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