The UV/Image Editor

The UV/Image Editor is the part of the Blender interface where you can see and adjust the UVs. It’s also useful when you want to load an image and use it for reference. Figure 8.2 shows an overview of the UV/Image Editor.

Figure 8.2 The UV/Image Editor and its options

The list that follows explains some of the main options available in the UV/Image Editor.

Interface: This is basically a normal Blender editor. It has its own Tools and Properties regions at the left and right sides, the workspace is in the center, and there is also a header on which you can find buttons for most of the options.

2D cursor: The 2D Editor has a cursor that is similar to the 3D cursor; you can use it to align vertices or other UV elements. Place it with a left click and, with Shift + S, you’ll see the snap options you can use with the 2D cursor.

Display panel: In the Properties Region, you can see the Display panel that lets you customize how you see the UVs; it even has a Stretch option, which shows the distortion based on the angle or area of faces in the UV map compared to the 3D model. It’s quite useful for identifying complicated areas. If the faces are very stretched (a blue face is good and a turquoise face is not bad, but you should avoid green and yellow faces), the texture will probably look distorted or it will be of poor quality when you project on that surface.

The header provides quite a few options.

Header menu: View, Select, Image, and UVs menus are available; the UVs menu is especially important, as it provides most of the unwrapping tools.

Loaded Images List, Create New Image, and Open Existing Image: You can load images, choose some from the drop-down list that have been already loaded, or even create new ones right inside Blender (like a solid-color image or a UV Test Grid, which you’ll see later).

Pin content: If you click on the Pin icon, the current image will be pinned and always shown independently of other objects you have selected. However, this tool doesn’t work with UV editing, only with the image you display in the UV/Image editor because the editor shows only the UV layout from the object you’re working on in Edit Mode. This option comes in handy when you want to display a reference image in the UV/Image Editor.

Work Mode: In the Work Mode menu, you can choose between View, Paint, or Mask modes. View is the usual mode you’ll use to adjust UVs and view images. Paint Mode allows you to paint directly in the 2D image when you’re in Texture Painting Interaction Mode in 3D View as well (see Chapter 9). Mask is a special mode in which you can create masks that you can use later in the Node Compositor to isolate parts of an image.

Pivot Point selection: The Pivot Point works exactly the same as in the 3D View; you can select the pivot point from which to rotate or scale objects and, for example, that’s how you can use the 2D cursor as a pivot point. As with 3D View, you can press . (period) and , (comma) on your keyboard to switch between the 2D cursor and the center of the selection for the pivot point.

Sync UVs and 3D View selection: The tool that synchronizes the UVs selection with the 3D model can be useful in complex modeling to find out where a specific vertex or face in the model is located on the UVs. Keep in mind that using this mode all the time may not be a good idea, as it limits some options for unwrapping.

Selection Mode: In the UV/Image Editor, you can switch between Vertices, Edges, Faces, and Islands selection modes. (An island is a group of connected faces.) You can also select an island, similarly to the 3D View, by pressing L.

Shared Vertex selection options: Shared Vertex options are interesting. Let’s say that on the UVs, Blender treats each one of the faces separately, but it allows you to select vertices depending on certain conditions, such as if the vertices share their X, Y, and Z position, in the actual 3D model. When this option is disabled and you select a vertex or a face, it will move alone and the connected vertices or faces will stay in their current places. If they are overlapped in the UV/Image Editor, the Shared Location option will treat them as if they were welded on the UVs, but only if they share the same location in the 3D model. The Shared Vertex option will select the vertices that share the position in the 3D model, even if they’re separated on the UVs. The best way to understand this is to try it out.

Proportional Editing and Snapping options: You also have Proportional Editing and Snapping tools in the UV/Image Editor to help you manipulate UVs.

Current UV Map: The UV Map name is pretty important because in Blender, a single object can have different UV maps that can be used independently when building complex materials, so you can use two textures that are differently distributed depending on the UV map they use. UVMap is the default name and, most of the time, you’ll only be using a single map. If at some point you want to create other UV maps, you can go to the Properties Editor and look for the UV Maps panel on the Mesh tab.

Update other views automatically: The last icon you’ll see on the header is a lock. This option, when enabled, will make other views in Blender show real-time updates while you adjust UVs. If you’re using an old or slow computer, you may prefer to turn this feature off and save resources.