Question: choose material/material file when loading scene about assimp HOT 3 CLOSED

What rendering implementation are you using (OpenGL etc)? For example in OpenGL, assimp would parse the .mtl file for texture paths, and the paths would be in the aiScene object -- you would need to load those textures separately in OpenGL (bind to texture objects etc as usual) -- so you could override texture paths there and leave the .obj/.mtl files alone.

Would expect there'd be similar seams in other rendering flows (WebGL, vulkan etc) where you'd be able to replace the requested textures, and could bubble all the way up to the UI so the user could select from available options (if that was in scope for your project and under your control)

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I am using OpenGL.

assimp would parse the .mtl file for texture paths, and the paths would be in the aiScene object

So instead of doing scene->mMaterials[mesh->mMaterialIndex] to get the material I loop through all materials in scene->mMaterials and load the textures from all materials in the scene? And then pick one of the materials when rendering a mesh? I guess this would work, but if I understood correctly, I would have to modify the .obj file for every new material added. Is there any way to process material files separately from the .obj (maybe there's a problem not knowing which faces to apply the material to, but I would be fine with all faces by default) so I don't have to change the model file constantly?

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There are two supported ways to change the materials. In code you just can select a different material by changing the material index of the mesh. And you can create a new mtl-file and reference this in your obj-model. There is a statement which describes the materiallib to load: mtllib .

But you must guarantee that all textures are there.

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