VAT - Vertex Animation Textures

Animating vertex animation textures for plants

🗏 View page source ✐ Edit this page ✎ Create child page

Quickstart

  • Install “Game Tools” under get extensions in blender. Should be able to search it. (Make sure you have newest version of Blender)

  • Make your animation with morphs, geo nodes , modifiers, whatever. Animation can live in NLA tracks but doesn’t have to. As long as things move when scrubbing the timeline, it will work.

  • Select your mesh (or meshes! The tool will auto merge) and check out the game tools tab. Open up “VAT Baker”

    {{0xc000cbaf00 0xc000cbaf00 image.png alt text alt text 0xc00075cd80} 0 false}

  • Change the frames setting to scene if you aren’t using NLA, and manually set the frame range

  • You can rename the resulting mesh under “Mesh”

    {{0xc000cbaf00 0xc000cbaf00 image-1.png alt text alt text 0xc00075cfc0} 1 false}

  • Hit bake up at the top. In the same folder as your blender file, there should be an FBX and 2 .EXR texture files

    {{0xc000cbaf00 0xc000cbaf00 image-2.png alt text alt text 0xc0009b2fc0} 2 false}

(Remember to check normals, face orientation, and remove any custom nrml data before baking)

  • Import all three files into UE
  • Run the plant import script
    {{0xc000cbaf00 0xc000cbaf00 image-3.png alt text alt text 0xc0007e01e0} 3 false}
  • Select “Use Animation Texture” to auto setup the anim
  • It might look a bit funky (spiky, anim not quite right) - if that is the case, double click the static mesh and set “Use Full Precision UVs” to true, then click apply changes
    {{0xc000cbaf00 0xc000cbaf00 image-4.png alt text alt text 0xc0007e04e0} 4 false}
  • By default the anim plays as a loop. There’s an option to change it to be directly driven by an alpha that we can trigger in a BP
  • I can add traditional looping in ez, or any other anim options
    • Add speed control

Official documentation