How to render the quadrilateral？

[SunnyXJ]

Hello, I want to render the quadrilateral, but there is no feasible method. Can anyone give me some suggestions?

[ponchio]

Hi,
just open the model in Meshlab and use the filter Turn into a pure triangular mesh.
(you could do the same thing using blender).

Motivation:
Multiresolution requires a fast, robust simplification algorithm; we opted for quadric based edge collapse, which wont
work on quad meshes. Quad meshes are not usually big enough to warrant use of a multiresolution approach,
so we didn't bother to implement a pipeline just for quads.
Moreover, when you render a quad, the graphic card just splits the quad into 2 triangles anyway.

[SunnyXJ]

Thanks ponchio,
I think my statement may not be clear enough, I need to display quadrilaterals or triangles, or a mixture of both, depending on the actual document. I need to see the actual gridlines, not just display objects.

[ponchio]

Hi,
I am afraid nexus is the wrong tool.
This library is designed for large datasets where the individual triangles are very small (a few pixels).

If your dataset is small, nexus is definitely not the right tool.

If your dataset is big and created using a CAD, the major obstacle is the simplification algorithm.
In theory it would be possible to adapt nexus to quads/mixed provided an open source simplification algorithm exists, 
with some modifications to the code and some shaders in ThreeJS.
I would need to have a look at the models to get an Idea of how suitable your use case is.

[SunnyXJ]

Hi, The file in the attachment is just a small demo. This is my custom data format. First, convert the file into a xxx.ply file (because I don’t know how the quadrilateral should be output in ply, I temporarily output the json file xxx.mesh). Then use nexus to convert ply into nxz, and the page reads the nxz file for execution render. Looking forward to your reply, thank you very much. Federico Ponchio ***@***.***> 于2023年2月22日周三 20:28写道：

…

Hi, I am afraid nexus is the wrong tool. This library is designed for large datasets where the individual triangles are very small (a few pixels). If your dataset is small, nexus is definitely not the right tool. If your dataset is big and created using a CAD, the major obstacle is the simplification algorithm. In theory it would be possible to adapt nexus to quads/mixed provided an open source simplification algorithm exists, with some modifications to the code and some shaders in ThreeJS. I would need to have a look at the models to get an Idea of how suitable your use case is. — Reply to this email directly, view it on GitHub <#149 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AJKMOWJBDZWKHXT7PVIFKBDWYYA5HANCNFSM6AAAAAAVCO22CU> . You are receiving this because you authored the thread.Message ID: ***@***.***>

[ponchio]

Which attachment? Maybe write directly to ***@***.***

…

On Thu, Feb 23, 2023 at 3:25 AM SunnyXJ ***@***.***> wrote: Hi, The file in the attachment is just a small demo. This is my custom data format. First, convert the file into a xxx.ply file (because I don’t know how the quadrilateral should be output in ply, I temporarily output the json file xxx.mesh). Then use nexus to convert ply into nxz, and the page reads the nxz file for execution render. Looking forward to your reply, thank you very much. Federico Ponchio ***@***.***> 于2023年2月22日周三 20:28写道： > Hi, > I am afraid nexus is the wrong tool. > This library is designed for large datasets where the individual triangles > are very small (a few pixels). > > If your dataset is small, nexus is definitely not the right tool. > > If your dataset is big and created using a CAD, the major obstacle is the simplification algorithm. > In theory it would be possible to adapt nexus to quads/mixed provided an open source simplification algorithm exists, > with some modifications to the code and some shaders in ThreeJS. > I would need to have a look at the models to get an Idea of how suitable your use case is. > > — > Reply to this email directly, view it on GitHub > < #149 (comment) >, > or unsubscribe > < https://github.com/notifications/unsubscribe-auth/AJKMOWJBDZWKHXT7PVIFKBDWYYA5HANCNFSM6AAAAAAVCO22CU > > . > You are receiving this because you authored the thread.Message ID: > ***@***.***> > — Reply to this email directly, view it on GitHub <#149 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAUDV27MWCHSHFRJPYJROILWY3DB5ANCNFSM6AAAAAAVCO22CU> . You are receiving this because you commented.Message ID: ***@***.***>

[SunnyXJ]

ponchio@gmail.com,I sent to. Is this yours.

[ponchio]

I got no email from you to ponchio@gmail.com, could you send it again?

[SunnyXJ]

yes, I sended it again.

[ponchio]

I had a look at the model and nexus is really a bad fit for such a model: I do not know any simplification algorithm that could do a decent job on such a model (mixed triangle and quads, cad model, nasty spirals!).

Wireframe on mixed content is hard already on the web, without the multiresolution stuff, implementing it in nexus would be a nightmare...

I think you should work more on splitting the dataset in object and apply LOD techniques.

[SunnyXJ]

thanks, I need more try.