Another little ditty…
As you can see on the image, some weird things is going on with the curtains. It seems like inverted normals, but if you zoom in close, the gap seems to be non-aligned vertices. They are merged though and very much aligned. All normals face outwards. History is deleted. Triangulated before export. Exporting through another file (format). Neither correct this.
Any thoughts?
This could be the old Z-buffer problem. Please check whether the gaps in the curtain have the same coordinates as your wall. If thats the case try to change you curtain coordinates in way that the curtain is as bit more in front of the wall.
Check for duplicate polys and 2 point polys along edges. Those will consistently cause that type of error. (I get it all the time if I don’t check my models before export)
Jeff
We also have had several objects (bookcases, whiteboards, countertops) that when viewed up close in the Unity engine look fine, but when backed away from start to show whatever objects are behind them through the edges where two polygon quads join. In each case, the objects are completely closed and all vertices are welded, there has been a complete exterior to the object and the interior face that shows forward has not been coplanar with the back of the object (the objects exterior has thickness), and it only occurs on surfaces that are concave to the hull of the object (parts cut into, extruded into, or attached into the exterior surface angling away from the camera view).
Also, the distance between the objects exterior and another object behind it has no impact on the outcome, so an object placed 1m away from a wall surface will show the exact same seaming issue as one placed with it’s back face coplanar to the wall.
It also appears that this issue always shows up on the nVidia graphics cards we use, and always shows up in the Macintosh OS when viewed in the Unity engine, but does not always show up in the Windows OS on ATI cards in the Unity engine Windows executable build. For example, three Windows OS only systems one desktop system with an integrated Intel video chipset, one laptop system with an nVidia 7800, and one desktop system with an nVidia 7900 always show the seaming issue. Also a laptop system with the Macintosh OS and an ATI x1600 with 256 meg of RAM video card also shows the seaming issue. The system that I am using is a Mac Pro 2-processor dual-core Intel Xeon with an ATI X1900 XT graphics card with 512 meg of RAM, using Boot Camp to dual boot operating systems on separate drives. Running the Unity executable build for the Windows OS under Windows XP with service pack 2 and the most recent ATI drivers and Catalyst 7.5 hotfix software I do NOT see the seaming issue on any of the objects, however when I boot into the Macintosh OS (10.4.9) and run the Unity build I DO see the seaming issue.
I’ve attached an example image of our invisible seams. Everything I’ve seen of this shows me that it is not an issue with the models, but something else (I have used other real-time engines and not seen this kind of problem with similarly modeled assets). What I’ve found that does seem to fix the issue for the moment is either detaching and scaling up any interior face where the seaming occurs, or to duplicate the exterior faces, flip their normals, and scale them in slightly. I’m hoping to submit our test files through the formal bug report process to hopefully determine a root cause and solution that doesn’t involve having to incorrectly model assets.
