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In this tutorial, Jarlan Perez covers the process of unwrapping a hard-surface model in 3DS Max. Covering the importance of keeping UVs clean and stretch free, Jarlan also looks at how to keep the process as simple as possible, whilst at the same time giving you full control over the results.
In the download you will find a folder named “Max Scene.” Inside the folder are two Max files - the start and end files for this tutorial. You can either follow along with the start file scene, or with a model that you've created yourself.
Let’s get started! Go ahead and launch 3Ds Max and open the “unwrap_Start.max” file. Inside you should see an unshaded wall shelf object. This object is not super complex but it has enough faces and different shapes to allow me to show the different techniques and how to apply them.
Additional Files/ Plugins:
- Download the Reference Materials for this tutorial
We'll begin by setting up a checker pattern. A checker pattern? Why in the world do we need a checker pattern? Well it actually will become a very important part of our unwrapping process. With the checker pattern applied we can visually see where stretching is occurring in our maps, and go on to easily fix the problem.
Go ahead and open the material editor by going to Render > Material Editor in the top menu of Max or by simply hitting the shortcut M.
Once in the material editor, select a material slot (Figure 1 in the picture below) in which to build you checker pattern. Next, under the Blinn Basic Parameters, you’ll see three properties named Ambient, Diffuse, and Specular.
We want to add our checker pattern in the Diffuse property. Click on the little Diffuse square (Figure 2 in the picture below).
Clicking that square will bring up the Material/Map Browser. From that list go ahead and double click on the Checker map.
Now that the map is loaded into our material, we want to setup tiling so that we can see a little more clearly where stretching will occur. Under the Coordinates section locate the U and V Tiling and change the 0 to a higher value like 20.
Click and drag the material you just created over to your model.
Even though we dragged the material over to our model it still shows up grey. To make our checkered material visible we have to toggle on one more setting. With your material selected click the Show Standard Map in Viewport button (shown below). The checkered pattern should now be visible in the viewport.
Looking at our model we can see that there is some very bad stretching going on. We’re going to fix that now!
First and foremost we’re going to have to add an unwrap modifier to our model. To do this, go to the Modifier dropdown menu and select the Unwrap UVW modifier.
Once you’ve added the modifier, we’ll be able to edit our model's UVs. In the Parameters section of the Unwrap modifier there’s a big button called Edit… (shown below) Go ahead and click that button to bring up the Edit UVW window.
This window contains all you UV information for your model. As you can see the UV layout is all over the place and it’s very hard to tell what is what (shown below).
Trying to texture a layout like this will get you terrible results and bring about lot of frustration. So we’re going to be laying them out in a way that allows you to know exactly where everything is, which will make your texturing process a lot simpler.
3Ds Max has a nice little way to automatically flatten every single face in your model and make a perfect starting point for laying out UVs for hard surface models. To begin flat mapping, in your Unwrap modifier select face (shown below) from the drop down or hit 3 on your keyboard.
Once you’ve done that, move over to your Edit UVW window and select everything in there either using click, drag, select, or by simply using the shortcut Ctrl+A.
Next go up to the top toolbar and click on Mapping > Flatten Mapping…
This will bring up the Flatten Mapping window. In this window you’ll find several properties, however I tend to leave these at default when I use this method, as it's only really being used as a starting point. Go ahead and leave the settings as they are and click Ok.
As you can see our UV layout is already much cleaner that it was previously, and you can now identify specific areas of the model. It's still not perfect though, and we'll need to arrange thing a little better so as to take advantage of as much of the UV space as we can.
Before we continue with our unwrapping let go ahead and set up a shortcut for the Stitch Selected command, which will make our lives much easier during this process. In the top menu of Max click on Customize > Customize User Interface…
In the Customize User Interface window locate Stitch Selected from the list (figure 1 in the image below). Once you find it we’re going assign a hotkey shortcut to it. In the Hotkey field you can add whatever shortcut key you want to make it. I personally use the letter S just because it makes sense (figure 2 in the below image). Once you’ve added this in, click the Assign key to make it official (figure 3 in the below image).
To make sure that your shortcut has been assigned, locate Stitch in the list view again. The key combination we just added in should appear next to it.
So what does this Stitch thing do? It’s simple. First select the edge option in your Unwrap modifier. Now if you select any edge in your UV map, it will show you any other edges connected to it on the 3D model, by highlighting them in blue. For instance in the image below, our red selected edge is connected to the top blue edge on our model. The Stitch command re-arranges the UVs so that these two edges sit correctly together in the UV map, and then Stitches them together.
Start selecting edges, remembering to look for the blue highlighted edges on disconnected UV sections. When you find one, hit Stitch to bring them together. Once you've done this several times, you'll see something similar to the image below. In it, the only highlighted edges are already attached to the same UV section, and don't require stitching! That's when you know that you can move on to the next area.
Continue moving from piece to piece, stitching all of the disconnected sections together as explained above.
After going through the entire object and stitching all of the disconnected pieces together, you should end up with something similar to the image below :
Looking at our model now we can see that it looks much better than it did before. However, there is still some stretching going on in our UVs, but this is a simple fix.
In the Edit UVW window toolbar we can find several Scale tools. In the image below, figure 1 scales everything uniformly in all directions, figure 2 scales your object horizontally, and figure 3 scales your object vertically.
Go through your model and find the areas where stretching is happening and correct them with the scale tools, by scaling the connected UV sections. Note : Make sure to select the entire sections, not just individual polygons as that will add even more distortion into your map!
Once you’ve finished scaling all of the sections, your checkers should be as close to perfect squares as you can get them. Having them square is a sign that you have a very minimal amount of stretching in your textures.
We’re almost finished! The only thing left to do now is to organize the individual UVs so that they fill up as much of the UV space as possible. The more space we can get them to fill whilst maintaining square, evenly-sized checkers, the more resolution we will be able to have in our final texture maps, which is only a good thing! Right now however, our pieces are everywhere.
Go back in and use the previously mentioned scale tools to fit all of your pieces inside the UV border as best as you can.
You can scale larger or smaller depending on your needs but make sure that your checker squares stay as close to the same size as possible. This will ensure that you have an even distribution of quality/resolution when you add your final textures to your model. If one area takes up a lot more of the space, it could look a lot sharper than the other sections in the final render.
The thing here is consistency so try to keep the sections as close to each other as possible as you can without overlapping!
Once you lay everything out as suggested above you are all set to start texturing your model!
I hope this demonstration was helpful and if you have any questions feel free to leave a comment below!