This is a repository that contains a simple tool to convert Alembic files to Vertex Animation textures.
It's working for the simple cases I've tested, you may find cases with issues ... I'm aware of that, but that project is provided AS IS, I will not provide any support for this, you have the code, you have some samples and it's provided for free.
Be sure to have the Alembic and Editor coroutine package installed in your project
Once done, all your resources are created and imported in your project automatically. You can drop the xxx_prefab object created and drop it in your scene. To animate the VAT, just change the Time position in the material.
The tool have generated 2 textures :
The provided shader has been made with Amplify shader editor and you can easily modify it to match your needs. If you want to create an HLSL shader or HDRP/URP shader, it's pretty straight forward. You need : A texture property called _VAT_positions where you'll have your vertex positions texture A texture property called _VAT_normals where you'll have your vertex normals texture A float property called _Framecount that will contain the number of frames in your animation (NOT the duration, the frame count)
In your vertex shader : The RGB of the VAT_normals texture will be the XYZ of the local vertex normal - it's already in a half format texture, you DON'T need to multiply by 2 subtract 1 like you do on a normal The RGB of the VAT_positions texture will be added to your vertex local position (or set as your Local vertex offset) The texture coordinates to access those 2 textures are in the SECOND UV SET, not the first one. So you can keep the texturing on your object To this UV2 you have to add to the X component the offset to go to the wanted frame. So it will be something like frameNumber*1/Texture width.
You can use freely the provided Alembic files, it's just simple tests, feel free to do whatever you want with them
I may or may not update that project again, I have no plans for the moment ... it was just a 2-3 days quick project made to help my students use more efficiently their Alembic files, on any platform, for a very cheap cost.
Feel free to use the tool in your projects, improve it, modify it ... Just don't sell it and make profit out of it please, it is free on purpose.