Comparing static mesh cube, plane, and a paper2d sprite with a lit material it appears that we've changed how we calculate the vertex normals for paper 2d sprites, see below:

[Image Removed]

Steps to Reproduce

Using the attached project:

  1. Open the attached project, Paper2DWSN, as version 4.23.1
  2. Observe the Paper2d sprite's normals
  3. Switch the project's version to 4.24 and open it
  4. Observe the normal direction of the Paper2d sprite has changed

From Scratch:

  1. Create a new, blank project with vanilla 4.23.1
  2. Create a new, default lit material as below called SpriteMaterial
    [Image Removed]
  3. Create a new Paper2d Sprite asset, using any engine texture as the Source texture
  4. Apply your SpriteMaterial as the default material for this new sprite asset
  5. Drag the sprite into the mapo
  6. Change your view mode to Buffer Visualization -> World Normal
  7. Observe the sprite's normals
  8. Save your map as "TestMap"
  9. Close the editor, and change the project's version to 4.24
  10. Open the project with 4.24, and open TestMap
  11. Observe the sprite's normals do not match the normals from 4.23

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Fix Commit11560206
Release Commit11560207
CreatedDec 12, 2019
ResolvedFeb 20, 2020
UpdatedJan 9, 2023
Pull Requests
6493 - heavybullets