Developer Notes

Not a Bug - use Full Precision UVs with large offsets


When a user sets up an unwrap using a space outside the original 0 to 1 space the unwrap will increasingly show errors of positioning. For Example, in the following images the lower left vertex of the plane is +0.0001 units, lower right vertex is at -0.0001 units. As the Unwrap moves away from the original 0 to 1 space, the small texture wrap increasing grows.


[Image Removed]

Also Reproduced in Main Promotable-CL-2564509 & Releases/4.8/Promoted-CL-2560772

Steps to Reproduce

(Instructions specific for Maya but was also reproduced in 3DS Max)

  1. Create a Plane in Maya
  2. Open the Texture View Window
  3. Select the Lower Left UV vertex
  4. Execute "polyEditUV -v 0.0001"
  5. Select the Lower Right UV Vertex
  6. Execute "polyEditUV -v -0.0001"
  7. Export All as an FBX named UVTest_Original.fbx
  8. Select all UV vertexs
  9. Execute "polyEditUV -u 20 -v 20"
  10. Export All as an FBX named UV_Test_UV20.fbx
  11. Import Both created FBXs into the level

RESULTS: UV_Test_Original.fbx and UV_Test_UV20.fbx despite being in the same 1 to 1 environment there is a huge difference in that 0.0001 vertex movement.

EXPECTED: There should be no difference in the unwraps.

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Affects Versions4.
CreatedMay 27, 2015
ResolvedMay 27, 2015
UpdatedJul 14, 2021
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