Is there any way to get the Texture from a PngImageFile object? #145

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1. fishbotics commented on Mar 3, 2024

   

   fishbotics

   on Mar 3, 2024

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   After some more reading, it seems like the easiest thing to do might be to dump the trimesh object into a BytesIO stream and then load it as an ObjFile, but there is no current support for loading textures from obj files (see #27)

   Another strategy I tried was to take the PIL texture object, dump it into a BytesIO buffer, gran the whole buffer, and then try to instantiate a meshcat.geometry.PngImage object directly, but this also didn't seem to work. Maybe the way I'm converting between objects wrong.

   Basically I did the following:

   im = mesh.visual.material.image
   if im is not None:
       buffer = BytesIO()
       im.save(buffer, format="PNG")
       binary_image_data = buffer.getvalue()
       image = meshcat.geometry.PngImage(binary_image_data)
       material = meshcat.geometry.MeshPhongMaterial(
           map=meshcat.geometry.ImageTexture(image=image)
       )
   

   But this doesn't seem to work with my PNG. In the original OBJ file, I think there are UV coordinates specified to map the texture to the file. Is there something I need to do to make that mapping work?
2. kielnino commented on Mar 22, 2024

   

   kielnino

   on Mar 22, 2024

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   Your approach looks right to me. Have you tried to save the png to an file and load it with

   material = g.MeshLambertMaterial(map=g.ImageTexture(image=g.PngImage.from_file(path_to_texture_file)))

   Another problem may be a missing MTL-File. I often see a combination of a .obj file containing the mesh, a .mtl file containing the mapping, and finally the texture itself.