Is it possible to give a texture a real-world scale?

Support Materials and Textures
#1

Hi!

Since a few months I’m using Blender for professional purposes. For the city of Amsterdam I make (relatively quick) impressions from the future situation of the urban environment. Sometimes I run into difficulties. For examples if a textures has to be assigned with a certain real world scale.

For the global accurate modeling I use a CAD application, where also the textures with the right scales are assigned. It would be handy if this also could be done in Blender.

I think this possibility would also have an increased value for architectural visualizations.

What I’m trying to achieve (give a texture a real-world scale):

Voorbeeldtexture Blender forum
Voorbeeldtexture Blender forum2661×2661 4.06 MB

Is this possible in Blender?

Thanks!

Louis

#2

Let’s start with the map first:

#3

Yes. If your model is real world scale, then your texture is show real world scale.

Example, your model 1x1 m. Then if you use Texture Scale = 1, your texture show 1 m. if Texture Scale = 0.5, your texture show 0.5 m., etc. etc.

#4

What kind of texture coordinates are you using?

If using object coordinates, keep object scales meaningful, and it’s easy. At scale 1, 1 unit in object coordinates is 1 unit in Blender (is 1m in RL, or whatever scale you’ve adopted.)

If using UV coordinates, consider creating a “standard scale” camera: an orthographic camera, set to orthographic scale 1.0 (in properties/object data/lens.) You can adopt the view of this camera and u->project from view to get real world UV scale (1 UV unit = 1 Blender unit.) You can shift 7 on a dominant face and ctrl alt numpad 0 to get the camera there, then project, if you want. Following projection, you can pin appropriate faces and then do a regular unwrap on the others. But of course, there’s no such thing as a perfect 2D->3D mapping, so be aware that your scales won’t be perfect.

If using generated coords-- well, don’t use generated coords. They’re no good for controlled scale. Anything you can do with generated coords, you can do with project from view UV (although, sometimes, requiring 2 maps.)

1 Like
#5

Thank you Bandages,

I think that’s a good method for many situations.

It should be a good addition to blender if there was a function in the shading- or UV-editor where the real world scala of a texture can be fillend in. In program’s like 3ds Max, Sketchup, or even the cad program I work with there is one.
Is there a place where these kind of wishes can be brought to the attention of the developers?

Regards Louis

#6

Thank you Lehuan5062,

I was following the YouTube movie where this parametrische shader was made. I didn’t had a very good result. The Blend file can be a good starting point for future shaders of paving materials.

1 Like
#7

Using object coords, as mentioned, makes it easy to get a real world scale reference. If you have to use UVs, you can scale the UV output to match the reference output from the object coord based.