Mapping Guide

Now that you have your mesh done you’re going to texture it or maybe  bake some maps and texture, in any case you’ll need to map it first.

First of all we’ll have to decide how we want to map our mesh.

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For that we’ll have to consider such things as how much texture space we’ve got and for what view we’re mapping. As this is horns for Outworld Demovourer, this means we’ll see them a lot in the portrait view. We’ll have to use as much of the texture space as possible, for that we’ll use a lot of mirroring. This means that different parts of our mesh will use the same texture space.

If we had 256×128 texture space we would probably mapped only this part of the mesh (1/4 of the mesh).

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Using this same texture space for the rest of the mesh, but because we’ve got whooping 256×256 texture space, we’re going to map half of the mesh.

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Now this is the reason why we need to build our geometry symmetrical as much as we can, this will allow us to practically double the size of our texture.

As the Dota 2 design guide says: “Texture seams are better kept to a minimum as they break up the vertices and add to an item’s vertex count.”, so it’s better to map in big chunks, but don’t sweat it.

We;re going to use Max for this, 3Dmotive got some awesome Maya unwrapping tutorials, as well as some great hand-painting texture tutorials.

So after you’ve decided how and what you’re going to map, let’s go to the Unwrap UVW.

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As you can see, after some optimizing our map looks like the projection, but this is not suitable for us. Just select everything and press Projection -> Planar Map

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Keep in mind that there’s bunch of mapping tools and techniques, but for this case we’ll need some simple mapping. If you’re modelling a weapon that’s mostly flat, it’s better to flatten out your map as much as possible, so it’s easier to paint your texture.

For example, see how’s the Valve-made weapon for Naga is mapped:

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Note the use of simple, clean geometry, extensive use of standard, box shapes, and pretty flat projection of the blade.

Now, after you’ve projected your map it’ll look like this

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Notice that green edges are the seams, and we’ve got some wonkynnes on top. To help us even out the map we’ll relax a bit. Or rather, relax our map a bit. Just select everything and press Tools -> Relax

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After some relaxing you’ll see that our map is now evened out

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Now we need to fit it into our texture space. So we’ll rotate and scale it a bit. If you remember geometry, the most line space we can get out of the square is the diagonal so if we rotate it diagonally we’ll get the most of the texture space, right? Well, not really.

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If we position it like that we’ve got A LOT of unused texture space, and the second downside is that we’ll get some unwanted downsizing bugs when mapping diagonally, see the Anti-Mage blades for the example.

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So what we’ll want to do with our map is to fit it into the square as much as possible.

For that we’ll have to scale some parts down and try to fit it. First rotate it for easier scaling.

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Then make sure it’s filling the space horizontally by scaling it

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And we need to fit our horn bits into the box.

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And the top one.

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And some scaling to fit.

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Some lining up of the root part

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Now we’ll check our mapping. Press CheckerPattern to activate checker pattern on your model.

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As you can see, there’s some stretching around, but nothing too extreme. But we still will try to fix it!

Select all.

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Tools -> Relaxhorn027

Check “Keep Boundary Points Fixed” and relax it a bithorn028

And some manual vertex moving will make it pretty good.horn029

And after dropping our bake we see that everything looks lovely!

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From all the angles!

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There’s a lot to consider when unwrapping, bigger things that will be in the camera the most should be allowed more texture space, things that will be obscured like the backsides or handles should use less texture space.

Seams should be placed where they’re most likely to not be seen, like in the natural depressions or hard edges. While with the Dota 2 texture size this is not the issue mostly (hell, some of the official models got some nasty seams, but they’re hidden most of the time) sometimes it could be very important.

Make sure to check out some more unwrapping tutorials, as this is a complex process and with some cunning will allow you to reuse some of the parts of your texture many times on the same mesh. This way you can make the most out of the limited texture size in Dota 2.

Mirror as much as you can and see the results of this tutorial here: