How to warp images on a deformable mesh using only Canvas 2D API

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A developer built a browser-based tool called Paper Animator that maps photos onto animated, paper cut-out style meshes without relying on WebGL. Since Canvas 2D lacks native texture-mapping for arbitrary quadrilaterals, the author solved this by splitting each mesh cell into triangles and applying a computed affine transform with a clip region per triangle. The animation system models rendering as a pure function of time, meaning identical inputs always produce identical frames, which enables deterministic video export. A WebGL2 fast path is layered on top of the Canvas 2D fallback, with both backends sharing the same vertex data so a seamless switch occurs if the WebGL context is lost. Caching static layers separately from per-frame mesh deformation keeps the pipeline efficient across both rendering backends.

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