# UV mapping - projection 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. ## projection **Projection** is the first step in the process. It is where you decide how the map should be applied to your mesh. You have a few options… - **Planar** adds a flat plane to your object - **Spherical** is good for rounded objects - **Cylindrical** is good for cylinders - **Automatic** is Maya’s best guess, usually doesn’t work The idea is to find the best approach for each section of your mesh. Rarely will you ever have a single projection method for an entire object. Usually you will use different projection types for different parts of your mesh. For example, the cylinder below has cylindrical projection on the round sides but the top and bottom have planar projection. ![[Pasted image 20230327113943.png]] The idea is to have your checker-board rectangles to be as close as square as you can get them. There should be as little distortion as possible. Sometimes that might mean [[UV mapping - cutting, unfolding, sewing|cutting]] your UV map into even smaller pieces. --- ### back-facing UV In your UV Editor, you want all your sections to be blue. You will sometimes see Red planes. These are planes that have backward normal faces (basically they are facing the wrong way). You can select the individual faces of your UV that are backward, however it can be easier to use the UV Toolkit to automatically select them. Simply click the **Back-Facing** button. ![[Pasted image 20230327115510.png]] Now that you have those faces selection, go to **UV Toolkit > Transform > Tools > Scale** and press the **Flip** button to get them facing the correct way. ![[Pasted image 20230327114133.png]] ### overlap You usually do not want to have overlapping UV shells. This would mean the same image map information would be used in both locations on your mesh. This can lead to weird graphics, especially if the map is applied through different projection methods. Fortunately, it is easy to fix. ![[Pasted image 20230327115733.png]] Select the faces of one of the shells in either the UV Editor or the Model Perp view. For easier selection, first choose the **UV Shell Selection** option in your UV Toolkit. ![[Pasted image 20230327120557.png]] Then move the shell in the UV Editor so there is no overlap. Use your basic **Move Tool** (CTRL/CMD-W). ![[Pasted image 20230327120712.png]] 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 smaller 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. For more information, check out **[[UV mapping - cutting, unfolding, sewing|Cutting, Unfolding, Sewing]]**. --- 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]]