Rig BakeRig Bake › Features › Advanced real-time exports: VAT, impostors & sprite stacks
Advanced real-time exports: VAT, impostors & sprite stacks
Three specialist bakes for performance-hungry games: vertex animation textures, octahedral impostors and layered sprite stacks.
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Beyond standard spritesheets, Rig Bake bakes three advanced representations used in high-performance and stylized rendering — normally the domain of custom in-house tooling.
Vertex Animation Textures (VAT)
Bakes skeletal animation into a texture so the mesh can play it back in a vertex shader — no skeleton, no animator, just one draw call per instance. Configure 2 to 256 frames and optionally bake normals. Ideal for GPU-instanced crowds, swarms and background characters in Unity, Unreal or custom engines.
Octahedral impostors
Renders the model from up to 32×32 viewpoints into an atlas (upper-hemisphere or full-sphere mapping), with optional normal and depth atlases. At distance you swap the real mesh for a single billboard that looks correct from every angle — the classic AAA vegetation/LOD trick, generated in your browser.
Sprite stacks
Slices the model into 2 to 128 horizontal layers for the "sprite stacking" fake-3D style popular in GameMaker and PICO-8 games — draw the layers with a vertical offset and the object appears 3D as it rotates.
Frequently asked questions
What is a Vertex Animation Texture good for?
Rendering hundreds or thousands of animated characters cheaply: the animation lives in a texture sampled by the vertex shader, so instances need no skeleton or CPU animation work.
Do impostors include normals and depth?
Optionally, yes — enable the normal and depth atlases for correct lighting and depth blending on the billboard.
How do I use a sprite stack in GameMaker?
Import the zip of slice images and draw them bottom-to-top with a 1px (or scaled) vertical offset, rotating each layer with the object angle.