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: 編輯模式
Tool: Toolbar ‣ Move, Rotate, Scale, Transform
選單: 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.

Randomize

Reference

Editor: UV Editor
Mode: 編輯模式
選單: UV ‣ Transform ‣ Randomize

Randomize the scale, rotation and offset of selected UV islands. The Randomize Transform tool in the UV editor works similar to Randomize Transform tool in the 3d view.

Random Seed: Changes the random seed used by the pseudo-random number generator, producing a different transform result for each seed value.
Location: Amount to randomize location.
Rotation: Amount to randomize rotation.
Scale Even: Apply the same scale to the U coordinate and V coordinate.
Scale: Amount to randomize scale in U and V coordinates.

Mirror

Reference

Editor: UV Editor
Mode: 編輯模式
選單: UV ‣ Mirror
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: 編輯模式
選單: 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: 編輯模式
選單: UV ‣ Snap
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 Round to Pixels below.
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.
Cursor to Origin: Places the cursor to the location (0, 0, 0).

Merge

Reference

Editor: UV Editor
Mode: 編輯模式
選單: UV ‣ Merge
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: 編輯模式
選單: UV ‣ Split
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: 編輯模式
選單: UV ‣ Unwrap
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: 編輯模式
選單: UV ‣ Pin/Unpin
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: 編輯模式
選單: UV ‣ Mark/Clear Seam

See Seams.

Seams from Islands

Reference

Mode: View mode
選單: 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: 編輯模式
選單: UV ‣ Pack Islands

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 islands, then individually translate each island so that they maximize the usage of the UV space.

Pack To
The UDIM grid to pack UV islands into.

Closest UDIM

Pack islands to the UDIM closest to the center of the selection.

Active UDIM

Pack islands to active UDIM image tile or, if no image is available, the UDIM grid tile where the 2D cursor is located.

Rotate
Allow islands to be rotated as well as translated to maximize texture usage.

Margin Method
The method to use when calculating the empty space between islands.

Scaled

Use scale of existing UVs to multiply margin. (The default from Blender 3.3 and later.)

Add

Simple method, just add the margin. (This is the default margin scale from Blender 2.8 and earlier.)

Fraction

Precisely specify the fraction of the UV unit square for margin. (Slower than other two methods.)

Margin
The scale for the empty space between islands.

Average Island Scale

Reference

Editor: UV Editor
Mode: 編輯模式
選單: UV ‣ Average Island Scale

Using the Average Island Scale tool, will scale each UV island so that they are all approximately the same scale.

Non-Uniform: Reduces average texture stretching within islands by scaling the U and V axes independently.
Shear: Reduces average texture shearing within islands by shearing the U axis.

Minimize Stretch

Reference

Editor: UV Editor
Mode: 編輯模式
選單: UV ‣ Minimize Stretch

The Minimize Stretch tool, reduces UV stretch by minimizing angles. This essentially relaxes the UVs.

Stitch

Reference

Editor: UV Editor
Mode: 編輯模式
選單: UV ‣ Stitch
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: 編輯模式
選單: UV ‣ Align
Shortcut: Shift-W

The Align tool will move the selected UVs to a line, where that line is specified in different ways by Axis.

The Straighten option will calculate a line segment between two endpoints and move all selected UVs onto that line.

The Align X and Align Y options will axis-align all selected UVs to the midpoint of the current selection.

Axis

Straighten: Move UV to closest point on line segment.
Straighten X: Move U co-ordinates onto the line.
Straighten Y: Move V co-ordinates onto the line.
Align X: Move U co-ordinates to the midpoint of the selection.
Align Y: Move V co-ordinates to the midpoint of the selection.
Align Auto: Choose between Align X or Align Y automatically.

Align Rotation

Reference

Editor: UV Editor
Mode: 編輯模式
選單: UV ‣ Align Rotation

The Align Rotation tool aligns entire islands to either the U or V axis.

The tool has three different methods of operation. The different methods specify the source for the alignment, and also whether to align with both the U and V axes, or just the V axis alone.

When using the Auto method, islands are aligned so that UV edges are aligned to either the U axis or the V axis. This method works best with quads and meshes representing organic subjects.

When using the Edge method, only the selected edges are considered, and the islands will be aligned such that the selected edges are aligned with the V axis. This method works with the selection, so it works best when a particular edge, or edge loop, needs to be aligned in UV coordinates.

When using the Geometry method, the geometry is taken into consideration. Either the X axis, the Y axis, or the Z axis can be used. Suppose the X axis is chosen. Using this method, edges which have a positive extent in the X axis will be rotated in the UV map so that the edge extends upwards in the V axis. This method works best to align multiple islands which share some common geometric property, either in the X, Y or Z axis.

Note that in the Auto method, edges can end up aligned either up or down or left or right depending on the orientation of the island prior to activating the tool. In the Edge method, the alignment of selected edges can be either up or down in the V axis, whatever is closest to the current orientation of the UV island. By comparison, in the Geometry method, the alignment will always be pointing up in the V axis, ignoring any previous orientation.

Show/Hide Faces

Reference

Editor: UV Editor
Mode: 編輯模式
選單: UV ‣ Show/Hide Faces

Reveal Hidden Alt-H
Hide Selected H
Hide Unselected Shift-H

Export UV Layout

Reference

Editor: UV Editor
Mode: 編輯模式
選單: 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: 編輯模式
Header: Proportional Editing
選單: UV ‣ Proportional Editing
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: 編輯模式
選單: 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.

Round to Pixels

During UV transforms, you can use Round to Pixels to help with matching features in the image or ensure your UVs have precise horizontal, vertical or diagonal alignment.

Note that Round to Pixels is applied after any snapping modes.

Disabled: UVs will not be rounded.
Corner: Will force the UVs to round to the corner of the nearest pixel of an image if loaded.
Center: Will force the UVs to round to the center of the nearest pixel 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: 編輯模式
選單: Face ‣ Face Data ‣ Rotate 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.

Reverse UVs

Reference

Editor: 3D Viewport
Mode: 編輯模式
選單: Face ‣ Face Data ‣ Reverse UVs

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