# UV mapping - cutting, unfolding, sewing UV mapping is the process of controlling how materials and textures are applied to your geometric mesh. Read the [[UV mapping overview]] to get a sense of the overall workflow. ## cutting Your mesh shapes can get complex in both form and desired materials. In that case, you will want to cut your UV maps into separate pieces, called shells or islands. The idea is to separate out the different sections much like you would different pieces of fabric in a garment. In the UV Toolkit you will find a section called **Cut and Sew** that lets you separate and recombine different sections of your model. ![[Pasted image 20230327122232.png]] In this example, I have a container of some sort and I want to add a different material texture to the liquid in the container. ![[Pasted image 20230327121959.png]] I’ve selected only the faces that represent the bottom of the container. Click on the **Create UV Shell** button to separate that section out into its own separate shell. Then move that shell so it doesn’t overlap or interact with other UV elements. ![[Pasted image 20230327122516.png]] Instead of cutting out by face, you can cut out sections using edges. Simply select the edges you would like to cut and press **UV Toolkit > Cut and Sew > Cut**. ![[Pasted image 20230327141248.png]] --- ## unfolding Unfolding allows you to take 3D sections from the mesh and flatten them out in the UV Editor. In my example, you can’t see the inside ring of the pot edge in the UV Editor. It is there, but not yet unfolded. ![[Pasted image 20230327132453.png]] I’ve selected the faces in my Persp view. Go to **UV Toolkit > Unfold** section and press the **Unfold** button. ![[Pasted image 20230327132853.png]] You can now see those faces in the UV Editor. They are attached to the top of the pot edge in a Planar projection. ![[Pasted image 20230327132958.png]] Instead of using Planar, it makes sense to change the [[UV mapping - projection|projection]] to Cylindrical. With those faces still selected, go to **UV Toolkit > Create > Cylindrical**. Alternatively, can use pull-down menus for **UV > Cylindrical**. ![[Pasted image 20230327133341.png]] You can now see that section as its own UV shell. ![[Pasted image 20230327133519.png]] Repeat this process to separate out your mesh sections as needed. It can be a time consuming project but the effort will be rewarded when you are able to easily apply your painted materials back on the object. --- ## seams and edges Since you are cutting elements into pieces and flattening them out, you are going to have a number of seams where the cuts appear. For example, the inside cylinder I cut above is laid out here in a rectangle. The highlighted red edges at either end of this rectangle are actually the same edge. That’s where the cylinder will be connected back up. ![[Pasted image 20230327134614.png]] Make the connected edges more visible by toggling on the **Shell Borders** icon at the top of the UV Editor (quick-key: 8). ![[Pasted image 20230327134717.png]] Seams are a necessary part of this process, you cannot avoid them. You can, however, make intelligent decisions in where you make your cuts. Changes in material or hard edges between elements. If nothing else, try to create seams that will be hidden away from the camera view so they are not obvious. --- ## sewing You can also recombine your UV shell pieces together when appropriate using the Sewing Tools found in the UI Toolkit. The best approach seems to be simply reattaching separated edges. I have a section cut out of the top edge of my pot and I want to connect it to the inside edge. _(no idea why, but it works for the demo.)_ ![[Pasted image 20230327141627.png]] Select the three edges on the cut out portion of the top rim. The corresponding edges will highlight on the other shell. **UV Toolkit > Cut and Sew > Sew** to stitch those edges back together. ![[Pasted image 20230327141900.png]] --- Learn more… - [Mapping UVs](https://help.autodesk.com/view/MAYAUL/2023/ENU/?guid=GUID-F5882F28-2430-4D17-9C30-77B0390727AE) - [Displaying and Selecting UVs](https://help.autodesk.com/view/MAYAUL/2023/ENU/?guid=GUID-764C4EB5-7050-477B-B866-76FE86758E7D) - [Editing UVs](https://help.autodesk.com/view/MAYAUL/2023/ENU/?guid=GUID-1189210D-218B-4327-8B4B-EB4E3C47A824) --- tags: #3d #maya #resources home: [[! 3d modeling- maya]]