UV Tools

The UV Room works with Paint Objects. If you wish to UV Map a Retopo Object, you can do so from the Retopo Room. A Retopo Object  must have a UV Map before Baking to a Paint Object. That said, note that the UV tools in both rooms are exactly the same, and this page contains all of the UV Unwrapping information.

To unwrap an Object (Paint or Retopo), it first must have UV Seams. By marking and having UV Seams, 3DCoat will know where to cut the mesh and lay it flat for texture application, via 3D and 2D means (3DCoat’s Paint Room, Photoshop, etc.).

When altering an existing UV Map, small changes to model topology are sometimes desirable. These adjustments being made in the Retopo Room, first, followed by Unwrapping the modified mesh and bringing the new Map into the UV Room for final island positioning and packing. At any time in the UV Mapping process, new seams can be placed and new maps created, which vary from those layouts made in the Retopo Room.

You can specify which unwrapping algorithm you wish to use. There is LSCM unwrapping, ABF++ unwrapping and 3DCoat’s proprietary GUUV unwrapping method (Globally Uniform). Further, you can also perform projection unwrapping. When you mark a new seam, 3DCoat unwraps islands in real-time and shows you the preview of the unwrapped clusters immediately so that you can see the degree of distortion for every polygon on every island. Having this convenient function helps to keep you from forgetting the location of any seam or cluster.

3DCoat also supports the creation and editing of multiple UV maps on a single mesh, but note that polygons cannot be shared across UV Maps.

Let’s take a look at the tools.

UV Tools


Add Clusters

Use the LMB to add a cluster center directly on a polygon face. Clicking again on the same face will remove it. This tool lets you mark local selections of polygons, or clusters, and marks the bordering edges of these clusters as UV Seams, allowing for a whole UV island to be split into parts with little work.

Mark Seams

When you are ready to unwrap your mesh to create a UV Map, you must first of course select your seams. That is where this tool comes in. You can select edges with the LMB, edge loops with SHIFT+LMB, deselect with CTRL+LMB and CTRL+SHIFT+LMB to deselect edge loops.

Edge loops

This tool is the same as holding down SHIFT+LMB with the Mark Seams tool. It is available as a stand alone tool for convenience.

UV Path

Allows the selection of vertices which are interpreted by 3DCoat to provide the path for a connected series of edges, which are marked as unwrapping seams.


UV Pack Area

Allows you to define the packing area of the current UV Map.

Clear clusters

Clears all UV clusters (also called UV islands) and seams.

Clear Seams

Clears only the seams of the current mesh.

Auto Seams

Mark UV Seams automatically with a “best guess” on what edges to select as the seams.

Sharp Seams

Specify a a surface angle between polygons to determine UV Seams. Useful for hard surface UV Mapping.


Fits all islands into the UV space.

Pack UV

This will pack all unwrapped UV clusters onto the UV map, according to a guide rectangle which you define. When this operation is complete, you can then edit the islands on the UV map. At this point you can perform many essential functions which require a UV map.


Pack the current UV Islands in the UV Map, overlapping islands will be moved, but not scaled or rotated. No unwrapping performed, only packing.

Pack UV2

Pack UV Islands without rotation or flipping. They will be scaled and moved for efficient packing.

Auto Scale

Scale all UV Islands to have equal proportions between World Space and UV Space.

Update Islands

When you have an existing island, and further mark a seam on that island causing it to become two, you will need to perform the Update Islands command to carry that information to the UV Preview Panel so that you will then have those two UV islands selectable, in the UV Preview Panel.

Restore UV

Restores UVs from the Paint Object in the Paint Room. Note that if you Apply UV-Set, it will be too late to use this function because any changed made have already been applied to the Paint Object.

Apply UV-Set

Applies the current Unwrap to the Paint Objects and/or Retopo Objects.


You can also save and load seam and cluster information of the current scene so it can be edited later. Note that this does NOT export or import a UV map.



Clears the selection.


Inverts the selection.

Rotate CW

This will rotate the selected island clock-wise.

Rotate CCW

This will rotate the selected island counter clock-wise.

Flip U

This will flip the U of the UV map.

Flip V

This will flip the V of the UV map.


Applies a light smoothing across the selected cluster (or island) to relieve stretching or pinching.

Cloth Relax

Relax UV Islands so that opposite edges on UV Seams will get almost the same length and relation between edge length in space, and edge length in UV Space. This is useful for making real items for patterns, such as clothing and stuffed animals.


Unwraps the mesh with the ABF++ algorithm.


Unwraps with 3DCoat’s proprietary unwrapping algorithm, Globally Uniform. Great for all types of meshes, be they organic or hard surface.


Unwraps the mesh with the LSMC algorithm.

To Planar

Uses Planar projection for Unwrapping selected UV Islands.


Hides your current selection.

Inv. Hidden

Inverts hidden parts to be visible, and visible parts to be hidden.


Unhides only selected faces.

Unhide All

Unhides all faces.


(To be documented)


(To be documented)

Copy UV

Copies the selected UV elements to the clipboard for later use. Copying another selection will override the previous.

Paste UV

Pastes UV elements to the current UV Map, that was previously copied to the clipboard. When using copying/pasting symmetrical or near identical islands, 3DCoat will automatically snap similar vertices to one another, allowing you to stack multiple UV Islands atop one another for texture space sharing.

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