[brodie_geers]

I've always eyeballed my textures in SU and used relative mapping in the Maxwell material editor. I'm thinking for consistency and speed that I might switch over to the real world scale option though. Just want to make sure this is the proper workflow.

Insert material in SU and change UV scale to 1mx1m in the SU Material panel.
Adjust Maxwell Material settings so that each map is set to Tile XY / Meters method

That's pretty much all there is to it right?

What if my image map isn't representative of a 1mx1m section? For example I've got a concrete material that's maybe .7mx.7m or I've got a grass material that's probably 3mx3m. How do I accommodate that?

-Brodie

[JDHill]

I don't understand why you would do that -- SketchUp's native texturing system is inherently real-world scale already.

What if my image map isn't representative of a 1mx1m section? For example I've got a concrete material that's maybe .7mx.7m or I've got a grass material that's probably 3mx3m. How do I accommodate that?

That is the point of using real scale in the first place; you would set the first one to 0.7m sq. and the second to 3m sq. All that is really going to happen inside the engine is that instead of squeezing 3 copies of the texture into UV space (i.e. what happens when you use relative scale), the engine is going to squeeze in 1/3 copies. That is, it simply applies the reciprocal of the stated tile value and hopes that the UVs on the object are indeed sized at 1m in the model. There's no magic -- if UV space isn't sized at a meter, the tiles will accordingly be too big or too small.

[brodie_geers]

Hrm, well my issue is that I'm going to be swapping back and forth between SU and 3ds max I think. If I were just in SU it probably wouldn't be a big deal but I'm hoping to find a good solution that will keep me from having to always eyeball things in either program. I see what you're saying about SU being inherently real world scale since you can type in say .7m x .7m and be done with it but since 3ds max seems to work differently I'm trying to find a unified solution. Since the relative/meter mode has to be determined inside the actual material it seems to make sense to do it all the same and it seems like real world will be more reliable for 3ds Max.

So just so I understand, for my image that represents .7m x .7m of concrete I'd set the material up in Meters mode for all the maps, no problem. Then in SU I'd set the size to .7m x .7m?

Perhaps that's not as helpful as I thought. In that case, I'd need to remember that my concrete is .7m x .7m and that my grass is 3m x 3m, etc. for every material. I was hoping I could get around having to remember all of that information or having to keep track of it.

-Brodie

[JDHill]

Personally, I'd stay away from that approach; real scale can be made to work to some degree in applications with loosely defined texturing systems, but it is going to fight with applications like SketchUp. Personally, I'd have removed it from the system long ago. Let's just walk through it:

Say that you have this 3m texture; naturally, you will set its size at 3m in SketchUp. So far so good, because SketchUp will create a 3m texture space, and show you the texture tiled precisely one time in that space, yielding a real tile size of 3m in your model. Perfect, you think, until you export and find your texture rendered 3x larger than expected. Why did that happen? Because your real scale MXM tells Maxwell to render each tile at 3x the size of UV space, which it expects to have been normalized at 1m, rather than the 3m which is required to show it at that size in SketchUp.

How can the plugin help you resolve this conceptual incompatibility? There are really only two ways: (a) it could force all of your MXM tile values to 1.0, so that they fit into SketchUp's UVs the way that SketchUp is showing them, or (b) it could rewrite all your SketchUp UVs during export. The problem with (a) is that maybe you really did want some texture squished down a hundred times to create a directional scratch pattern; the plugin just wrecked your material. The problem with (b) is that you are visually controlling the positioning of your UVs in SketchUp; when the plugin rewrites them, how should they be positioned? With the UVs rewritten, your render will never match your viewport.

So just so I understand, for my image that represents .7m x .7m of concrete I'd set the material up in Meters mode for all the maps, no problem. Then in SU I'd set the size to .7m x .7m?

No, in SketchUp, you'd need to set the size to 1m. If the texture represented 10m and was set up for real scale in your MXM (i.e. meters mode, repeat values of 10.0), you'd still set the size to 1m in SketchUp. Because regardless whether a texture uses real scale or not, it still operates relative to UV space, and that space must be 1m for the real scale math to work as expected.

There exists a purely op-in workflow here which loosely follows option (b) above: you can use the plugin's UV Overrides with a UV Override Size of 1.0 set in plugin Options. You will not have control over how the textures are positioned, but they will work with real scale MXMs, since you'll be telling the plugin to write 1m UVs (naturally, this only makes sense for planar/cubic projections), regardless of what SketchUp is currently using to show you the texture.

That's what I can tell you about SketchUp -- I hope I've written it clearly. Unfortunately, I have no idea how texturing in 3dsmax works, so I can't really say much about what might be a good workflow there.

[brodie_geers]

Thanks for the detailed info JD. I'll have to think through my workflow a bit more. I'm certainly questioning whether it will simplify things at this point or just bring about more headaches.

-Brodie