Editing
After unwrap, you will likely need to arrange the UV maps, so that they can be used in texturing or painting. Your goals for editing are:
Stitch pieces (of UV maps) back together.
Minimize wasted space in the image.
Enlarge the faces where you want more detail.
Re-size/enlarge the faces that are stretched.
Shrink the faces that are too grainy and have too much detail.
With a minimum of dead space, the most pixels can be dedicated to giving the maximum detail and fineness to the UV texture. A UV face can be as small as a pixel (the little dots that make up an image) or as large as an entire image. You probably want to make major adjustments first, and then tweak the layout.
Transform
Reference
- Editor
UV Editor
- Mode
Edit Mode
- Tool
- Menu
Move G
Rotate R
Scale S
Shear Shift-Ctrl-Alt-S
Axis Locking
Transformations can be locked to an axis by pressing X or Y after one of the transform tools. Also, holding the MMB will constrain movement to the X or Y axis.
Mirror
Reference
- Editor
UV Editor
- Mode
Edit Mode
- Menu
- Shortcut
Ctrl-M
UVs can be mirrored on the Y axis or the X axis:
Mirror X
Mirror Y
You can also use the hotkeys X or Y, or hold the MMB and drag in the mirror direction.
Copy Mirrored UV Coordinates
Reference
- Editor
UV Editor
- Mode
Edit Mode
- Menu
Copies UVs from one side of the mirrored mesh to the other. Affects only selected vertices (on both sides).
- Axis Direction
Positive/Negative
- Precision
Tolerance for finding vertex duplicates.
Snap
Reference
- Editor
UV Editor
- Mode
Edit Mode
- Menu
- Shortcut
Shift-S
Snapping in the UV Editor is similar to Snapping in 3D. For the snap to pixel options to work an image has to be loaded.
- Selected to Pixels
Moves selection to nearest pixel. See also Snap to pixel above.
- Selected to Cursor
Moves selection to 2D cursor location.
- Selected to Cursor (Offset)
Moves selection center to 2D cursor location, while preserving the offset of the vertices from the center.
- Selected to Adjacent Unselected
Moves selection to adjacent unselected element.
- Cursor to Pixels
Snaps the cursor to the nearest pixels.
- Cursor to Selected
Moves the Cursor to the center of the selection.
Merge
Reference
- Editor
UV Editor
- Mode
Edit Mode
- Menu
- Shortcut
M
- At Center
Moves selected UVs to their average position.
- At Cursor
Moves selection UVs to 2D cursor location.
- By Distance
Merges selected UVs within the specified Merge Distance.
Split
Reference
- Editor
UV Editor
- Mode
Edit Mode
- Menu
- Shortcut
Alt-M
- Selection Y
Splits (disconnects) the selection from the rest of the UV. The border edge to any non-selected elements are duplicated.
Note that the ”copy” is left exactly at the same position as the original, so you must move it to see it clearly.
Unwrap
Reference
- Editor
UV Editor
- Mode
Edit Mode
- Menu
- Shortcut
U
Blender offers several ways of mapping UVs. The simpler projection methods use formulas that map 3D space onto 2D space, by interpolating the position of points toward a point, axis or plane through a surface. The more advanced methods can be used with more complex models, and have more specific uses.
Pin & Unpin
Reference
- Editor
UV Editor
- Mode
Edit Mode
- Menu
- Shortcut
P, Alt-P
You can pin UVs so they do not move between multiple unwrap operations. When Unwrapping a model it is sometimes useful to ”Lock” certain UVs, so that parts of a UV layout stay the same shape, and/or in the same place. Pinning is done by selecting a UV, then selecting Pin from the UVs menu, or the shortcut P. You can Unpin a UV with the shortcut Alt-P.
Pinning is most effective when using the Unwrap method of UV mapping, for organic objects. An example is when you are modeling a symmetrical object using the Mirror Modifier. Some of the UVs on the mirror axis may be shared across the mirrored counterparts. You could pin the UVs that correspond to the midline, then align them on the X axis, and they will stay in that location.
Pinning also work great with the Live Unwrap tool. If you pin two or more UVs, with Live Unwrap on, dragging pinned UVs will interactively unwrap the model. This helps with fitting a UV island to a certain shape or region.
Mark/Clear Seams
Reference
- Editor
UV Editor
- Mode
Edit Mode
- Menu
See Seams.
Seams from Islands
Reference
- Mode
View mode
- Menu
Adds seams at the boundaries of existing UV islands. This is useful when modifying the UVs of already unwrapped meshes.
Pack Islands
Reference
- Editor
UV Editor
- Mode
Edit Mode
- Menu
- Shortcut
Ctrl-P
The Pack Islands tool generates an optimized UV layout with non-overlapping islands that tries to efficiently fill the Texture Space.
First it will uniformly scale the selected island, then individually transform each island so that they fill up the UV space as much as possible.
- Pack To
The UDIM grid to pack UV islands into.
- Closest UDIM
Pack islands to closest UDIM.
- Active UDIM
Pack islands to active UDIM image tile or UDIM grid tile where 2D cursor is located.
- Rotate
Allow islands to be rotated to possible get a tighter fit.
- Margin
The target empty space between islands.
Average Island Scale
Reference
- Editor
UV Editor
- Mode
Edit Mode
- Menu
- Shortcut
Ctrl-A
Using the Average Island Scale tool, will scale each UV island so that they are all approximately the same scale.
Minimize Stretch
Reference
- Editor
UV Editor
- Mode
Edit Mode
- Menu
- Shortcut
Ctrl-V
The Minimize Stretch tool, reduces UV stretch by minimizing angles. This essentially relaxes the UVs.
Stitch
Reference
- Editor
UV Editor
- Mode
Edit Mode
- Menu
- Shortcut
Alt-V
The Stitch tool, will join selected UVs that share vertices. You set the tool to limit stitching by distance in the Adjust Last Operation panel, by activating Use Limit and adjusting the Limit Distance.
Align
Reference
- Editor
UV Editor
- Mode
Edit Mode
- Menu
- Shortcut
Shift-W
- Straighten
Auto, X, Y
- Align
Will line up the selected UVs on the X axis, Y axis, or automatically chosen axis.
Auto, X, Y
Show/Hide Faces
Reference
- Editor
UV Editor
- Mode
Edit Mode
- Menu
Reveal Hidden Alt-H
Hide Select H
Hide Unselect Shift-H
Export UV Layout
Reference
- Editor
UV Editor
- Mode
Edit Mode
- Menu
If you are using an external application, you need to know where on the mesh you are painting.
Muista
This is an add-on activated by default.
Proportional Editing
Reference
- Editor
UV Editor
- Mode
Edit Mode
- Header
- Menu
- Shortcut
O
Proportional Editing is available in UV editing. The controls are the same as in the 3D Viewport. See Proportional Editing in 3D for a full reference.
UV Options
Reference
- Editor
UV Editor
- Mode
Edit Mode
- Menu
- Live Unwrap
Continuously unwraps the selected UV islands while transforming pinned vertices. Note, this is different than the Live Unwrap option in the 3D Viewport.
- Snap to Pixels
- Disabled
UVs will not be snapped.
- Corner
Will force the UVs to snap to the corners of the nearest pixels of an image if loaded.
- Center
Will force the UVs to snap to the center of the nearest pixels of an image if loaded.
- Constraining to Image Bounds
For standard textures, this option prevents UVs from being moved outside the 0 to 1 UV range. For UDIMs textures, this option prevents UVs from being moved outside the nearest UDIM tile.
3D Viewport
Rotate UVs
Reference
- Editor
3D Viewport
- Mode
Edit Mode
- Menu
The orientation of the UV texture is defined by each face. If the image is, for example, upside down or laying on its side, use the (in the 3D Viewport in Face Select mode) menu to rotate the UVs per face in 90-degree turns.
Reverse UVs
Reference
- Editor
3D Viewport
- Mode
Edit Mode
- Menu
The tool mirrors the UVs per face, which flips the image over, showing you the image reversed.