Windows 10, NVIDIA Quadro P4000
Broken: official 2.79b (f4dc9f9d68b)
Broken: blender-2.79.0-git.de3f9303eb9-windows64 (de3f9303eb9 - 2018-10-18 18:21) (the latest I could find in builder.blender.org this day)
Short description of error
- Mesh in Blender ready to be exported as FBX (unwrapped UVs for one arrow, then Mirror modifier applied):
- As a result of the applied Mirror modifier, both arrows have the perfectly ovelapping UVs on top of each other (very commonly used technique in game development to save texture space):
- That FBX imported into Maya (thick white lines show the other arrow's UVs broken into several islands of single polygons, in other words, its UV polygons are not attached to each other anymore):
- To visualize the issue, here are all the UV islands separated individually with margins in Maya 2018:
Note 1 (Breaks): even that didn't get rid of the issue if I made a new cube, joined the mesh of the 2 arrows to the cube object and then deleted the cube mesh and after that exported the new arrows object as FBX. Same issue continued to happen.
Note 2 (Works, no issue): if I fully separate or even incredibly slightly offset the UV islands in Blender after applying the Mirror modifier and then export that object as FBX, they will appear perfectly as just 2 separate identical UV islands when the FBX is imported to Maya 2018, as is expected to happen in any case - this works as a workaround for now
Note 3 (breaks): in Blender, if I separate one of the UV islands by 1 unit in X-axis and after that move it back -1 unit in X-axis so that they once again align and overlap with each other perfectly, the same issue happens when exported as FBX and imported into Maya 2018.
Exact steps for others to reproduce the error
- Open the .blend
- Apply the Mirror modifier of the arrows object
- Export as FBX
- Import the FBX in Maya 2018