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Can anyone confirm this? "Real world scale" mapping does not create real UV-coordinates

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Hey all,

After using loft objects for creating roads and tunnels in 3DSMax, I discovered the sweep modifier. What I liked in it, was that I could create multiple roads within a single object (on multiple path splines), which is something the loft object type doesn't support. The problem with this, though, is that if the roads are of different length, adjusting the V-tiling for one road, results in a stretched/shrunk mapping for the other roads that differ in length.

At which point, I discovered the "real world scale" texture mapping. Using it, I found out that I'm now able to apply an even mapping for a certain distance traveled, which works nicely on roads of any length.

Now the problem is, that upon importing my little test into the level editor of the game, I noticed that the texture tiling is multiplied by at least 100x compared to what is seen in Max viewports. I returned to Max, used the UVW Unwrap modifier to examine the UV coordinates, and sure enough, the coordinates are showing some real wacky numbers for even the smallest vertex distance traveled in the edit window, even though everything seems to be fine in the viewport. Basically, even though my road texture seems like it is tiled only once on a polygon, the U and V-coordinates in the UVW Unwrap edit window are showing 200,200!

This leads me to believe that any setting regarding UV coordinates in the material editor, including the "real world scale" map width/height measurements, does not really affect the UV coordinates, and this doesn't export well. Am I correct?

I could have learned to like this approach to texture mapping, but it seems that if I continue this way, it won't be WYSIWYG anymore.

Unless, maybe, if...

1) ... I work with a smaller unit scale right from the beginning and adjust the "real world scale" bitmap width/height values accordingly (since metric units are oversized for the game), or
2) ... there is a tool to easily downscale all scene UV-coordinates by a custom value, whenever I want to export the scene for testing in-game?

I'd like to hear your thoughts and suggestions on this.

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Um, my guess:
real world scale means texels (the "resolution"), not normalized units (0....1). Try using a different texture with different resolution and look at the output. Or better, scale the image with an image editor. The roads in Max will look the same, but I bet the output will be different.

To solve this, you could try to use UVW Map modifier to each road object somehow...

Maybe I'm wrong, long time since using 3ds MAX...

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I'm exporting the scene as .ASE-files, which is simple but sufficient. I've never heard the term "baking modifiers" before though, so I can't tell if .ASE-export supports it. I suppose it's something like that which I need, or a tool which truly processes the UV-coordinates based on the settings in the material editor coordinates dialog.

[quote]Try using a different texture with different resolution and look at the output. Or better, scale the image with an image editor.[/quote]
I'm fairly sure this isn't it. When using real world scale mapping, you are expected to enter the measurements for each image. For example, if you have an image of the side of a car, you would enter something like 4.5 meters x 1.5 meters. These measurements should of course remain the same even if the image resolution changed, from 512x256 to 2048x1024, for example. After all, even though the image is now of a higher resolution with more details, it is still representing something that is 4.5 meters wide and 1.5 meters tall.

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Baking modifiers can mean "convert to poly" or "convert to mesh" (right click quad menu) for example. This means you cannot edit the modifiers any more, but the mesh should be exported perfectly (well, normals cannot be baked for some strange reason I can't understand. 3ds (it's own format...) doesn't even export normals at all....)

Something I would try before exporting...

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Ah yes, I often simplify my meshes into editable meshes, just didn't realize that was what the term meant.

Unfortunately, it doesn't make any difference... the ASE export already takes the 'end result' of the effects of any modifier stack, upon exporting. Besides, I don't think the material editor settings are technically considered a modifier anyway.

The problem remains...

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