Real world scale vs Uvw modifier
I’ve always used the UVW Map modifier for texturing until I got problems when reloading Revit(Cad)-scenes back into Max. When I don’t use the UVW modifier, no problems, which means I have to start using the real-world scale option in the ME.

So my question: In the UVW Map modifier you can set the Length, Width and Height (box mapping) of the texture, but in the ME there is only a Width and Height - what is the workflow..This real-world texturing is a bit new to me!

So my question: In the UVW Map modifier you can set the Length, Width and Height (box mapping) of the texture, but in the ME there is only a Width and Height - what is the workflow..This real-world texturing is a bit new to me!

The map you are applying is two dimensional, so you get two dimensions, Height and Width. This is the size the image would be in real life.
For example, You have a photographic texture of a concrete paving slab, the slab was 40cm square, so you would set the H and W to 40 and 40 cm. If the photo was of 4 slabs (2x2) set the size to 80 x 80, with six slabs (3x2) the size is 120 x 80 cm.
The UVW defines how it is applied to faces, real world takes care of the size.

In the UVW Map modifier you can set the Length, Width and Height (box mapping) of the texture…

To add a little to Samab’s answer: You said it yourself, Box Mapping.  If you chose Planar, there would only be width and height.  Box mapping adds the depth value, but in reality it’s just a reoriented width parameter.

Real World Texturing can be a little confusing at first, but definitely can save some time in the end.  Once you understand how it works, you’ll find it much easier to work with, especially when dealing with imported geometry that already has the mapping set up.

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