I’m using the latest Blender 4.5.4 LTS and am curious if there are faster or more automated ways to do UV mapping that I might not be aware of. Does Blender 4.5.4 have built-in advanced auto-unwrap or UV orientation features that can speed up the process without needing much manual rotation?
I don’t know why he rotates the UVs there, that’s completely unnecessary in this situation. The texture is symmetrical, so the UVs would only need to be scaled and translated here so the texture is aligned with the model.
There are 2 main ways to texture using UVs and the need to rotate islands will depend on which you are using.
The only time you really need to rotate UVs is if you need to map an existing texture onto an object and that texture’s rotation matters. Example: you have found a seamless wood planks texture for a floor. The floor’s UVs are going to have to be rotated so the planks are facing the way you want them. If that’s the way you are using textures, you will have to carefully unwrap parts of your model and place them over the texture so it’s correctly scaled and rotated on your model. However, an advantage of this method is that the UVs can overlap or go out of the square and it will work just fine.
However, if you aren’t adjusting a pre-existing texture to your object and are instead painting or baking a new texture from scratch, the UV’s orientation won’t matter because that new texture will match the UVs no matter their rotation. So if that’s your case, you can just use “smart UV project” as your unwrap method and then use the UV editor’s “pack islands” to fit everything in the square and it will work fine and be as close to an automated solution as possible (just make sure the pack islands tool has a little bit of margin, so the islands don’t touch each other).
Well. Author of tutorial knows because he probably made the mistake once, before recording the video.
Consequence of forgetting rotation would give an obvious result.
Texture would not be repeated horizontally but vertically, during following horizontal scaling of UVs.
He could have made a vertical scaling of UVs.
But he made a rotation to avoid dissonance of a vertical scaling of UVs for an horizontal repetition of texture.
You can allow it to auto rotate islands as needed to pack them tightly.
You can also choose to turn off auto scaling in the case that you want UV islands to have special scale values for certain parts rather than use one unified scale value.
I think there have been improvements in Blender since this addon.
Theoretically he might have some plans to use texcoord for some animations inside shader/vfx and in this case it will matter how its rotated. So if he have such plans and want to keep it in a certain way (keep things oriented towards U or V) - it makes sense.