Unwrapping the UVs
This doc goes over how to unwrap UVs for 3D assets using Tileable Textures...
Last updated
This doc goes over how to unwrap UVs for 3D assets using Tileable Textures...
Last updated
With the main texture imported, even if it is just the Diffuse texture, we can start unwrapping the UVs in order to tell the scale and application of the tileable texture.
The UV Editing layout has two main windows. The UV Editor on the left, and the standard 3D Viewport on the right.
Select the 'UV Editing' tab at the top of Blender.
Go into 'Edit' Mode on the asset and select some of the polygons. Notice how shapes will appear in the UV Editor.
The shapes in the UV Editor represent the polygons of your 3D asset. The goal is to get these shapes into their respective colors on the Diffuse texture.
Select the polygons you would like to be one color in the 3D Viewport.
Left click, Left drag, and/or [Shift] to multiselect.
Use X-Ray mode or [Alt + Z] to select through objects.
As tileable textures are usually used for large flat surfaces, the best UV tool is Smart UV Project.
Smart UV Project will take all the polygons and flatten them to the UV as best as it can. You can adjust some of the setting to do so before applying it, but the default settings are usually pretty good to get started.
Select all the Polygons you would like to flatten.
Select 'UV > Smart UV Project' in order to flatten your asset UVs.
Adjust the parameters as needed such as the angle in order to keep polygons connected.
Select 'Unwrap' on the popup.
Note that due to the texture being a 2:1 ratio the unwrap may be warped to align. Most tileable textures are 1:1 and will not require a similar fix.
Make sure that your asset Scale has been applied so that it will be Unwrapped at teh right scale.
Select the Asset.
[Ctrl + A] to pull up the Transforms to be applied.
Select 'Scale' to reset the Scale to 1.0.
You will notice that all the selected polygons will be placed within the UVMap according to the properties you set. You could then take these UVs and move them around the texture as needed with the standard Position, Rotation, and Scale tools.
Depending on the type of asset you are unwrapping you may need to get into the details and make sure some of the UVs are facing the right way etc.
The main thing you would need to do is scale and rotate the UVs so that the texture looks how you want. The UVs can go bigger than the UV Map texture size, as the texture is tiled. So you can adjust the scale of the UVs as you need.
It is a good idea to adjust the angle so that the environment doesn't look so square or right angled to the texture for things such as rocks, grass, dirt etc.
There are ways to reduce the appearance of tiling such as using terrains or custom shaders, but that will be covered in a future tutorial due to its complexity.
With more organic objects the smart UV Project approach may not work as well, although you could try and adjust the angle in the Smart UV Project parameters in order to have it break the edges, or Seams at higher angles.
If you want complete control over the seams, we can do exactly that. Set the Seams as you like, and then unwrap the asset with that in mind.
Select the edges [2] you would like to create a Seam.
Right click > Mark Seam.
Right Click > Clear Seam to remove them.
Once all the edges are marked, select all the polygons you would like to unwrap.
Go to UV > Unwrap.
Edit the UVs with Move, Rotation, and Scale.
You may find that your asset may not unwrap correctly or some seams make the unwrapped result warp when you want as much of the asset to be flat. This may be due to some edges not being marked as a seam when they should be.
Select the 'UV Sync Selection' tool at the top left of the UV Editor window.
Use the 'Edge select' tool to select the edges in the UV you would like to set as a seam.
In the 3D Viewport, right click and select 'Mark Seam'.
Once done, select all the polygons you would like to unwrap.
Go to UV > Unwrap.
Edit the UVs with Move, Rotation, and Scale.
Using the 'UV Sync Selection' tool is excellent for some situations, and annoying in others, so use as needed when unwrapping your UVs.
