MSFS20 gltf vertex color

[tsgucci]

Hi Arno!

When importing a gltf model to MCX the vertex color information gets lost. Is it possible to keep it somehow?
The MFSF material is still applied on the object, the polys have different vertex color, just no base color texture.


Thanks a lot!

 

[arno]

Hi,

Do you mean that this object has no color for the material that is applied and only a vertex color? MCX does not use vertex colors indeed, it only supports to set the color at the triangle level.

 

[tsgucci]

Hi Arno!


MSFS Material is applied on the object with white base color. But the different vertices - in my case different polygons - are "painted" with different vertex color. That pin what you see on the first picture is one object. Some polygons have yellow, others green and some red color.
If this object is inserted into MSFS it looks exactly as in 3DS Max.

Moreover MSFS encourages us to use vertex colors on lower LOD's.
From SDK:

• Low poly LoDs often do not need a texture at all, and you can simply use the vertex colour (this is essentially a "free" way to colour a model because of the single-vertex format.

 

[arno]

OK, sounds like I have to extend MCX to use the vertex color as well. Quick work around might be to at least read the vertex color and use it to set the triangle material right. But that would not give the benefits the SDK describes. Would you have a simple test object that uses some vertex colors? Might be just a few boxes.

 

[tsgucci]

OK, sounds like I have to extend MCX to use the vertex color as well. Quick work around might be to at least read the vertex color and use it to set the triangle material right. But that would not give the benefits the SDK describes. Would you have a simple test object that uses some vertex colors? Might be just a few boxes.

Yes of course!

Please give me a day.

 

[tsgucci]

Hi Arno!

I have exported the cone example for you.

The object looks exactly like in MSFS.

Thanks really a lot!

 

[GaryGB]

Hello:

IIUC, if MCX added the ability to process Vertex Colors, that 'could' potentially make other enhanced features possible.

Burn material colors into textures

Hi Arno: Regarding the following ModelConverterX (aka "MCX") feature as documented in the MCX wiki: "Burn material colors into textures When importing models from certain models it might be that a material has both a texture and a colour. Some systems mix those two on rendering, others don't...

www.fsdeveloper.com

SketchUp to a 3D object software for Texture Mapping

Hello I am just wondering, is there any 3D object software that can easily do a texture map by importing sketchup file? Long time ago, I did it with GMAX but the problem on the model in wire frame after import, there are plenty of vertices or triangles in one side of a box for example.

www.fsdeveloper.com

This may allow users of Sketchup and MeshLab to generate Ambient Occlusion via Vertex Colors ...and burn that into mapped Materials via MCX.

That could open up possibilities for another FS content creation work-flow via Sketchup without post-processing by 3DSMAX or Blender.


PS: It is interesting to see the processing functions ASSIMP is already able to work with:

Releases · assimp/assimp

The official Open-Asset-Importer-Library Repository. Loads 40+ 3D-file-formats into one unified and clean data structure. - assimp/assimp

github.com

GitHub - assimp/assimp: The official Open-Asset-Importer-Library Repository. Loads 40+ 3D-file-formats into one unified and clean data structure.

The official Open-Asset-Importer-Library Repository. Loads 40+ 3D-file-formats into one unified and clean data structure. - assimp/assimp

github.com

Assimp: postprocess.h File Reference

load different textures type using assimp

By default I load everything like this for(int g = 0; g < faces.size(); g++) { glMaterialfv(GL_FRONT, GL_SPECULAR, materials[g].Ks); glMaterialfv(GL_FRONT, GL_DIFFUSE, materials[g].Kd)...

stackoverflow.com

Thanks in advance for considering further extending this functionality in MCX.

GaryGB

 

[tsgucci]

Hi Arno!

Sorry I do not want you stress you on this one, I can imagine how busy you are. Is the vertex coloring planned to be implemented in MCX?

Thanks a lot!

 

[arno]

Hi,

Yes, it is planned to be implemented, but too be honest it also had slipped my mind as I was working on other features.

I have added it to the todo list now in the bug tracker:

Support glTF vertex colours (#5603) · Issues · SceneryDesign.org / ASToFra · GitLab

Support reading and writing vertex colours for the glTF format. MSFS can use this for models. https://www.fsdeveloper.com/forum/threads/gltf-vertex-color.452352/

gitlab.com

But it might take a while to finish it, as the summer holiday is about to start.

 

[arno]

I finally found the time to start with this feature. I am not sure how long it will take, as I will have to update the glTF reader, glTF writer, the internal data model and the MCX preview for this.

 

[tsgucci]

I finally found the time to start with this feature. I am not sure how long it will take, as I will have to update the glTF reader, glTF writer, the internal data model and the MCX preview for this.

Thanks Arno, it is great news. If you need any help like sample or testing just let me know.

 

[arno]

I think the sample you uploaded before the summer should be enough to get me started.

 

[arno]

Making progress, the reading and rendering is working now. Only the exporting I need to work on.

 

[arno]

Hi,

I have finished implementing this now. The vertex colors are now exported to glTF, COLLADA and FBX as well. So that means they won't be lost anymore when you work with your model in MCX. A new development release will be online later this morning.