Export OBJ vs Upload to Sketchfab Directly

Development Asset Creation
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1

Hi,

I´m a new user for RC. I have been using ***** for a lot of time and i think RC is fastest and the mesh have more detail. But, the question is:

I have a model with 244 cams (photos). The model show very good in the RC software but it´s have small wrong triangles in the corners and i would like to repair its.

If i upload directly the model to Sketchfab, it´s show fine, but i cannot edit the obj.
If i export the model as OBJ (for edit in Meshmixer or Upload directly to Sketchfab), it´s show terrible (the texture show low quality and over contrasted). I would like export the model, edit it in Meshmixer and then upload to Sketchfab. In ps, i export the model as obj it´s show fine in Sketchfab.

What i´m doing wrong?

Plase, see attached screen captures of the issue.

 

  • Screenshot of the RC screen. The texture shows very good.

 

  • Two scrrenshots of the model exported as OBj and uploaded manually to SketchFab. The texture is wrong, is dark, overcontrasted ¿?

  • Scrren capture of the model uploaded directly to SketchFabb via RC. It´s shows fine

  • Scrrenshot of the model created in PS (exported as OBJ)

 

What i´m doing worng?

 

Thanks a lot!

 

2

Hi Fernando,

you are doing nothing wrong! The large triangles are a result of the way RC generates the mesh. I think they are working on a way to avoid those artifacts, but for now we have to live with it. You can reduce the size of the bounding box slightly and use the filter “mark triangles outside box” to delete them.

Can’t help you with the texture problem though…

3

Thanks a lot of Götz!

I have repaired the artifacts as you said.

However, is important know why the OBj exported is not working propertly (probably some config ?).  Is very different the exported obj and the uploaded directly. I need work the models porccessed in meshmixer. If not.

For example,  not only the textures are wrong, mapcats shows diferent too.

For the exported OBJ and uploaded manually:

 

And here an screenshot for the model uploaded directly:

Anyone knows why?

Thanks!

4

Hi Fernando,

have you looked at the obj locally with another software before uploading to sketchfab? The look reminds me a bit of meshlab, where by standard texture and vertex color is switched on simultaneously which results in too dark a look - switching one of them off will fix that.

I did not understand the differences in geometry - the first screenshot shows a completely different part of the model and is also textured…

If it works fine directly from RC, why do you need to do it manually?

5

Hi Götz,

Yes, i have imported the model in meshmixer and the look is similar than sketchfab.

My workflow is export the model and import it  in meshmixer for postproduction purposes, and then upload to sketchfab or 3DPrint.

I don´t have control for model uploaded directly with the “upload to sketchfab” option. For example, control the number of the tiles and the size, control the size of the model, etc and via “upload” i don´t know what i´m uploading.

I have uploaded several models with diferents options in the export mesh window, but similar results

Thanks!

 

6

Sorry, I don’t know what it could be out of the top of my head. Does that happen with other projects too? It might help if you post a screenshot of your texturing settings and maybe some export settings as well.

7

Yes. I tried some diferent options but nothing

 

8

And the obj export settings? Did you try to set Export Vertex Colors to False?

Do you observe the same behavior with other project?

9

Settings:

vertex colors off:

 

vertex color on:

 

Is my first model with this program. 

I don´t know how to solve this.

 

 

 

 

 

10

Hmm, I use Number Format: Double - no idea why, it’s always been like that.

Also, I don’t export normals.

Have you tried using a larger Maximal Texture Resolution?

I don’t have any experience with Sketchfab (although I should). Could it be that it wants one texture file only?

 

11

HI

I have compared two mtl files, the generated with RC vs Others

#
# Wavefront material file
# Created in RealityCapture v1.0.2
# www.capturingreality.com
#

newmtl Monsalud_cuarto_Material
Ka 1 1 1
Kd 1 1 1
d 1
Ns 0
illum 1

 

Where said Kd  i replace for  Ks and now is viewing fine in Meshmixer. Now  i´m uploading to sketchfab, i´ll reply when uploaded.

Best

Fernando

 

12

Hey Fernando,

wow, nice idea!

Did it work?

Anybody any idea what’s going on here?

If not, I think you should report it as a bug.

13

Hi Götz,

Work, but texture shows terrible. Very low quality. I don´t know what’s hapening :(.

If i export the texture with only one file, the model shows propertly as you said (locally in Meshmixer and remotely in Sketchfab).

If I export the texture of the model in parts, the model and the texture don´t show propertly (locally and remote).

I don´t know if there are one forum about bugs, i think so. If so, i will post this issue.

Oh, here is the model: https://sketchfab.com/models/d35e6c55a8f74507811b6b43b1d71de0

 

Thanks a lot!

Fernando

 

14

Could it be that you are, in that case, viewing the model with vertex colors only ?

For “low” resolution meshes that can result in looking like the texture is of a terribly low resolution.

15

Hi Shadow

I don´t think so.  

As said, the diference is if export texture as only one jpg file, it’s show fine. But if export texture as parts, it´s show terrible.

 

16

I don’t think its vertex colors, the mesh has a much lower poly count.

Fernando, did you try the texture resolution 16k x 16k?

17

Hi Götz,

No, i don´t try 16kx16k because i choose 42 jpg parts textures, and 16x16x42 is huge. 42 parts in 2x2k

In this moment i´m rendering another model for testing. 

18

Hi Fernando,

the thing is that you would need only ONE 16k because 2k fits in there 64 times (8x8) !  :slight_smile:

So I would try 16k or at least 8k - that should give you a better resolution if you force it to put everything on one texture file.

19

Hi

Just render another model, and verified the issue:

Here, an screenshot of the model just generated the obj, without change anything int the MTL file.

Here, an screenshot of the obj file opened in Meshmixer. Left side, with single JPG texture, and right side, exported with multipart jpg texture and replaced in the MTL file the Kd word for Ks word.

 please, see 100% size: https://support.capturingreality.com/hc/user_images/fQ3oTzQcObGCj9wpEEGNKA.jpeg

 

 

20

The bottom left one looks ok to me. So is that the 16k version?