Merge mesh and multimaterial

[Dad72]

I found run bug when we merge two objects that are a multimaterial.

The object is well merged. Once I serialize it to record it and reload my scene. Some of the textures are missing.

On the first image, these are my two objects that I want to merge. There is a metal ring around.

But once merge, and serialize the object merge, the metal has disappeared.

[MarianG]

Hi Dad72. I think you have to set a materialIndex foreach  merged mesh. line41.

[Dad72]

Ok, I did not know that we had to use that.

Thank you MarianG.

I wonder if this can not be automated directly into the engine when the merge?

[Guest]

Nope as this could be a unwanted option

[Dad72]

@MarianG,

No, it did not work. this solution took the iron texture on the first model and texture 2 on the second model.

Why does not this merge correctly?

Compare with the first image of the barrel :

In your PG example, each model has its textures or colors.

In my case the barrel each model has 2 textures, but the gold of the fusion I lose the second textures.

[Dad72]

In fact the fusion does not seem to take into account when there are several textures. Or I do not know how to do it.

When I merge an object having only one texture is perfect, but with two, it's not right.

[trevordev]

Would it be possible to repro what you are seeing a playground I can take a look at?

Why is the merge required as apposed to creating a new mesh with the objects as children? Or is this for performance reasons?

[Dad72]

It's not necessary. It is to offer this possibility to the users of my editor.

My editor is for creating MMORPGs. Performance is therefore important for future users. I would like him to be able to merge objects if he wishes, just like the possibilities to create instances of objects, of group (parent/children) and many other useful things.

It's not for my own needs, but I'm sure it will be useful to my editor.

I will try to make a PG. Thanks for your help.

[Dad72]

I made you a PG here.  I struggled to load the model, the playground does not want more external file. So I used 'data:' and same thing I could not load the textures remotely. So I took texture from the playground.

Before, I could load remote models with http instead of https, but now it will be difficult to make PGs with our own model if it works more. 

http://playground.babylonjs.com/#1I4KHI#4

[Guest]

"I have galérer to load the model" ==> I struggled to load the model

 

[Dad72]

Oops 

[Dad72]

@trevordev,

Hello, 

I do not know if you saw the PG that you asked me. I have the impression that the subMaterials are erased by mergers. Because each submeshes to create one took into account the first subMaterial, but not the second one.

Can be a bug here ?

http://playground.babylonjs.com/#1I4KHI#4

[trevordev]

Thanks for the PG,

from the implementation of mergeMeshes it doesnt look like merging meshes the way you expect is supported right now.

Created github issue to track this: https://github.com/BabylonJS/Babylon.js/issues/5197

In your playground you are merging 2 barrels that have the same material on both of them, is merging 2 different objects with different materials also a scenario to you?

[Dad72]

When I test with two different objects, I have the same problem, it is the first sub-material that is taken into account on all the merge objects.

This only works if the object has only one texture, but not several sub-material.

Thank you Trevor