Blender Stack Exchange is a question and answer site for people who use Blender to create 3D graphics, animations, or games. It only takes a minute to sign up.
Sign up to join this community
This is my building with all of the faces of a wall selected:
When unwrapping the object, it looks like this:
The issue with this kind of unwrap is that, if I wanted to make the entire wall a brick texture, it wouldn't be possible to make a consistent brick texture across the wall.
To show you what I mean, I covered the UV map with a brick texture. This is the result:
So, my question is this: "How do I unwrap my brick wall so that I can easily make it look clean?"
In the 3d viewport use an orthogonal view that shows the wall you want to unwrap.
Select the faces you need. Press U and select Unwrap from view (bounds)
Then set your material so that it uses the texture using the coordinates of the UV map.
While unwrapping from the view in ortho works for most cases, you can end up with texture scale inconsistency due to zoom changes in the Viewport that way. And unwrapping from view bounds will always force the mapping into a 1:1 ratio, causing distortion on any geometry except for perfectly square planes. Also, aligning the view to each plane of structures like roofs can be tedious.
Instead I recommend this great add-on that will make your life easier when doing archiviz...
It was released way back in 2012 by Alexander Milovsky, but is still compatible with Blender 2.79. It only generates the UV data, so it doesn't rely on any specific render engine. And of course the add-on is not needed to open .blends made with it.
After the add-on is installed, these buttons become available in the Mesh context tab:
UVW Box Map creates a UV map that is basically a box projection. It's good for boxy structures.
Best Planar Map attempts to find the optimal planar projection. Similar to Project From View.
Both of these methods have parameters you can tweak in the Operator Panel, so play with those too.
Here's a test I did on a structure with various kinds of angles:
Textures courtesy of Pixabay. 1, 2 .blend available for download here.
The conical part of the roof was not handled well, so I unwrapped with cylindrical projection on that part, which was better but still pretty bad. I think for such shapes careful, manual seam-marking and unwrapping is required.
The semi-cylindrical protrusion on the side of the building also has imperfections - the seam is showing, it just isn't very noticeable with the brick texture.
You can see where the seams are when using a UV test grid:
Conclusions
The Sure UVW Map add-on can help save a lot of time when mapping boxy/planar geometry. It runs up against limitations when used on rounded geometry. Knowing this you can probably figure out where it is appropriate to use. Hopefully it will make your architectural visualization projects go more smoothly. I have found it useful on many occasions.
