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

Toolbar ‣ Move, Rotate, Scale, Transform

Menu

UV ‣ Transform

  • 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

UV ‣ Mirror

Hotkey

Ctrl-M

UVs can be mirrored on the Y axis or the X axis:

  • Mirror X

  • Mirror Y

You can also use the hotkey Ctrl-M, then enter 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

UV ‣ Copy Mirrored UV Coordinates

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

UV ‣ Snap

Hotkey

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

UV ‣ Merge

Hotkey

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

UV ‣ Split

Hotkey

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

UV ‣ Unwrap

Hotkey

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

UV ‣ Pin/Unpin

Hotkey

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

UV ‣ Mark/Clear Seam

See Seams.

Seams from Islands

Reference

Mode

View mode

Menu

UV ‣ Seams from Islands

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

UV ‣ Pack Islands

Hotkey

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.

Average Island Scale

Reference

Editor

UV Editor

Mode

Edit Mode

Menu

UV ‣ Average Island Scale

Hotkey

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

UV ‣ Minimize Stretch

Hotkey

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

UV ‣ Stitch

Hotkey

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

UV ‣ Align

Hotkey

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

UV ‣ Show/Hide Faces

  • Reveal Hidden Alt-H

  • Hide Select H

  • Hide Unselect Shift-H

Export UV Layout

Reference

Editor

UV Editor

Mode

Edit Mode

Menu

UV ‣ Export UV Layout

If you are using an external application, you need to know where on the mesh you are painting.

Note

This is an add-on activated by default.

Proportional Editing

Reference

Editor

UV Editor

Mode

Edit Mode

Header

Proportional Editing

Menu

UV ‣ Proportional Editing

Hotkey

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

UVs

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

Turning on Constrain to Image Bounds will prevent UVs from being moved outside the 0 to 1 UV range.

3D Viewport

Rotate UVs & Reverse UVs

Reference

Editor

3D View

Mode

Edit Mode

Menu

Face ‣ Face Data ‣ Rotate UVs/Reverse UVs

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 Face ‣ Rotate UVs (in the 3D Viewport in Face Select mode) menu to rotate the UVs per face in 90-degree turns.

The Face ‣ Reverse UVs tool mirrors the UVs per face, which flips the image over, showing you the image reversed.