Perfect UVs by Pelt Mapping in 3ds Max
UVs are the key to taking full advantage of 3D software. In fact, you can't do much without a good UV set. Many Important functions such as Displacement concept and Texturing are directly depended on an object's UVW mapping. So I've decided to show you how to create qualified UVs inside 3ds Max.
The UVW Unwrap modifier has a function named Pelt Mapping, which is a perfect tool for creating UVs for objects. I think in most cases, you don't need anything else for mapping objects. The Pelt Mapping method gives you sufficient ability to do most of the mapping job without even hand editing UVs. It works well for organic and inorganic objects.
Firstly you should have a clean mesh, meaning that it is better if your mesh has been created with all quadrangular faces, and has no extra vertices or any such cases. When you've got the mesh correct, then you are ready for the next step. So open up your object scene, select your object, navigate to the Modify panel/modifier list and apply a UVW Unwrap modifier from the list. Pelt function needs you to define the Pelt Seams on your mesh, so it can pull out the mesh using those seams. Thus it's very important that you place your seams carefully. In my case I was working on a head mesh and I so defined the seams as shown in Fig.01 & Fig.02.
Notice the blue lines which indicate the pelt seams? To define edges as pelt seams you can select the desired edges in the edge sub object level of the UVW Unwrap modifier and then in the Map parameters rollout click "Edge Sel to Seams". You can also quickly adjust the pelt seams by using the "Edit Seams" and "Point to Point Seams" options. If you select some faces or a part of the mesh and click "Pelt", the borders of the selected region will become pelt seams automatically.
When you have defined the seams then go to the face sub object level of the UVW Unwrap modifier and select part or all of your mesh and hit the Pelt button. As soon as you click, a window will appear and should show something like this (Fig.03).
The circle around the mesh, which is called "Stretcher", will pull out the mesh on the surface. The lines connect the circle's points to the seam's points of the mesh.
In the Pelt map dialog window, in the Pelt options rollout, under the Springs section, you can increase four spinner numbers, which will totally increase the pulling effect. Just make sure that "Lock Open Edges" is checked. Select the entire mesh by checking the "Select Element" check box and scale it down to a little size. This will give the stretcher more space to work. Then click the "Start Pelt" button and let the stretcher do its work. It will flatten out the mesh and in my case it turned to this (Fig.04).
It's something like a ghost! OK, now click "Commit" to apply the operation. In the Edit UVWs window navigate to Tools > Relax. You can also just right click and select the rectangle next to the Relax option from the menu to bring up the Relax Tool dialog window (Fig.05).
From the drop down menu, select "Relax By Face Angles" which is the best option to use if you want to get the correct results. Increase the "Iterations" and "Amount" values and this will increase the pulling effect. The Stretch value is better left at a low number. Now click "Start Relax" and let it get to work. When you feel it has finished, click "Stop Relax". In the Selection Modes section, check the "Select Element" option to select the entire mesh and then use the Scale and Move tools to scale down and place your mesh inside the dark blue rectangle (Fig.06).
Now to indicate the distorted areas, go to the Face sub object level and from the Select menu, click "Select Inverted Faces" and then the "Select Overlapped Faces" option. Each time, depending on the complexity of the mesh, you may see areas shown in red. They are distorted areas and need to be fixed (Fig.07).
To fix the overlapping areas, open up the Relax Tool dialog box again. From the drop down menu, select "Relax By Centers" - its function is to remove any overlapping. Use it carefully to remove the overlapping areas and then use the "Relax By Face Angles" option again to resolve the stretching effect that will appear, this time with a low Iteration and Amount value, something around 14 and 0.1. Remember that the Pelt Mapping method is somewhat depend on your ability to use relax tools to solve distortion and give you qualified results.
Finally, to resolve any inverted faces, you have to use the "Relax By Edge Angles" option. Always use low numbers for Iterations and Amount values and repeatedly click the "Apply" button to resolve problem areas. I'd advise you to add a Checker map to your mesh so that you can discover and inspect any distorted areas.
If there is any distortion remaining that can't be fixed by relaxation, then use the Move tool to manually move vertices and fix the distortion. If you fill some parts like ears and horns, which can't be flattened and fixed anyway, then select the edges of their margins and click "Break" from the Tools menu to part them from the mesh. Make a suitable seam, if needed, by selecting edges and then using "Break". Then use the Relax tool to resolve their distortions too.
If you have a complex UV set, then you may use Tools >Pack UVs. The dialog to easily packing UVs can be seen in Fig.08
Select the "Recursive Packing" option from the drop down menu, which is more accurate, and set the Spacing value as needed (this is the spacing between clusters). Check "Rotate Clusters" and "Fill Holes" on. Click OK and then hold on until it works out. If you don't like the result then you can try the layout manually (Fig.09).
Finally you should have a perfect UV set! Take a look at my head mesh, with fine-tuned UV mapping only using the pelt method (Fig.10)
To render the UV set for further texturing stages navigate to Tools > Render UVW Template and in the dialog box that appear, set a dimension for the image that is going to be rendered and then click the "Render UVW Template" button.
As you saw, the UVW Unwrap Pelt Mapping method is a great tool to easily, quickly and perfectly create UVs. Plus that there is no need to export and import things in and out of 3ds Max because everything happens inside the software. With Pelt Mapping you can also map inorganic objects in the same way as well, like cars, weapons, planes, even buildings and so on.
I hope this tutorial helps! If you have any questions, you can contact me at: email@example.com