I have been trying to make a space flight simulator in Unreal Engine, but I have an issue with the Starfury 3D model I borrowed - and when I say “borrowed” I don’t mean I stole it; I’m using it with the permission of the author. Anyway, the model was created in Blender for a different engine. I imported it in UE4, but it appears incorrectly textured.
What I get after the importing are all parts of the model (main hull, cockit, flaps, etc.) as separate skeletal meshes, each with its own physics material and a skeleton. Then, I also get one fully constructed skeletal mesh of the entire Starfury. My problem here is that all of the separate skeletal meshes are correctly textured, as seen on the screenshot below:
This is what the complete model actually looks like.
As you can see, the main hull and the greebles/guns almost look like they’re liquid. I’ve already tried modifying the materials and textures to no avail. There’s only one LOD, too, so that can’t be a problem either. What I can’t do (because I’m a complete bonobo at this) is getting the textures to show up in Blender. Maybe the problem comes from there, but I don’t know how to fix it even if it does come from there.
I’m not sure. Could it be retaining settings from the other engine it was created for previously? Some engines use X and Z horizontal axes and a vertical Y axis, which could mess up how it’s rendered or how it’s UV mapped and such in Unreal.
When I took a closer look at the model in Blender I noticed that the shading is very unclear there as well. I couldn’t get the actual textures to show up, though, so I can’t say for sure.
“SkeletalMesh compute tangents [built in]: Build result data contain 0 or NAN tangent value. Bad tangent value will impact shading.” - this is what I get as a warning
Is that warning in Blender or Unreal? I was looking at the exporter settings in Blender, and the importer settings in Unreal. In Unreal, the Import Options has an option to either “Import Normals Only”, “Import Normals and Tangents”, or “Compute Normals”. What did you choose for that? Import Normals Only and Import Normals and Tangents is for keeping what was done in Blender. Calculate Normals re-computes the normals and tangents within Unreal.
There’s three models in this package; I also tried to set up the Starfury’s materials. Main hull and guns/greebles are pitch black when rendered in Blender.
Well, the UVs looks fine and the material is compatible with them to tell you the truth I am not best with meshes, but I played a little bit here and there and all that I can say is something wrong with the mesh what exactly I don’t know but the group meshes that comes with it works quite fine(not as good as in the first pic you placed tough).
Anyway if you import that group to blender mirror the engines, move the group to the correct axis and export them as one mesh everything should work more or less fine. Sorry that I couldn’t help you completely but I am best at finding alternatives than fixing the problem, I hope that maybe @preston42382 can find a better solution.
I was using Blender last night, and there’s a number of display settings that need changing or enabling / disabling to get the render to display how you intend. I was having trouble with a simple model I made, in which I went to render it and it appeared completely white with hardly any shadowing or detail at all. When opening the model in Blender, at the right is a bunch of sidebar tabs (similar to details panel in Unreal but way more stuff). Try changing the settings in there, then go up to the top bar (File, Edit…etc) and select Render Image under the Render dropdown. It’s a refresh of the image / model with current settings. It may also be the Viewport Shading method (upper right just inside viewport, so may need to drag the sidebar border to the left for it to be visible) is set to the wrong type. I have “Display in Solid Mode” selected, whereas if I change it to “Look Dev” or “Render Preview”, it doesn’t apply all the settings I have set (such as Metallic).
When exporting from Blender, the forward axis and up axis need to be changed from the Blender defaults. I think Unreal is x-axis forward (or y-axis forward if it’s not that), and z-axis up, but not any of the negative xyz axes in the list of the export options. If it’s exported with the defaults, then it’s probably going to appear with the UV texturing and such in the wrong positions, and normals in the wrong axes. That’s how it appears the model is rendering in Unreal in the photo where it is messed up, with UVs flipped / mirrored / rotated oddly. I couldn’t unzip that .rar file yet because I need to download a free unzipping program and then be able to open it in Unreal 4.23.1.
Have you tried contacting the original designer of the model about this problem?
Indeed, it’s +X Forward and +Z Up in Unreal Engine. I’ve exported with those settings instead of the original (Blender) axises, still the same. The solid white issue also came up at one point, but I managed to fix it. Also, where I live, WinRAR has an infinite trial period (no joke), so you can use that to zip/unzip.
I haven’t contacted JSM, because he has long since stopped working on the project those models were meant for.
As my helpers stated before, this indeed is an issue with the UVs. It has nothing to do with UE4.
Today I decided to play around with the model in Blender. I tried to merge the different parts into one mesh and import that into the engine. While doing so, I also poked around the material slots and the UVs. What I discovered is, that the complete model (figure 2) was merged while the separate parts had different named UV maps (some even two or three different maps). After a very brief Google Search it turned out, that when merging many meshes into one, you have to match UV map names and make sure there’s only one UV map on each mesh - which wasn’t the case, as I already stated.
What you see on figure 2 is the result of Blender being set to render only one of the two UV maps present on the mesh; the other one is set to not be rendered, which is why it appears the way it does in both Blender and UE4. So by merging the UV maps, the problem was fixed.
TL;DR: UV maps were not merged; merge them into one map and the issue will be fixed.
Interesting that the UVs weren’t merged in the original mesh. How did it initially work in the author’s use? Maybe Blender unmerged the UV map, or all its UV maps if there were 2 or more merged maps to start. It may a setting that auto-unmerges UV maps, or an internal default. It might be important to note for working with other meshes in Blender, especially for import to Unreal.
Unfortunately, he was creating the models for a custom engine, which was never finished, so I have absolutely no idea. However, you may see the final result here:
