Straighten a selected Blender quad UV strip. Select one continuous strip of quad faces and straighten its UVs into a rectangular grid while leaving the mesh geometry in place.
You have one open strip of quad faces (a road, belt, ribbon, trim or pipe section) whose UV island is curved or uneven, and you want its UVs laid out as a straight, evenly spaced rectangle without changing the mesh.
Buy the Skadira bundle at /store/skadira/ and extract skadira-0.1.1-guide-bundle.zip. Keep program/skadira-0.1.0.zip zipped: Blender installs that inner ZIP. Open GUIDE.html for this manual and PRACTICE.txt for the worked exercise.
In Blender 4.5 open Edit › Preferences › Add-ons. Click the ▾ menu at the top right of the list, choose Install from Disk…, and select skadira-0.1.0.zip. Make sure Skadira UV Strip Straighten is ticked. To remove it later, use the same list: the add-on's ▾ menu › Uninstall.
Click one mesh object, press Tab for Edit Mode and switch to face select (press 3). Select one continuous strip of quads: no triangles, no branches, not a closed ring. Only one object may be in Edit Mode.
In the 3D Viewport or the UV Editor press N to open the sidebar and click the Skadira tab. The Straighten UV Strip panel shows what it needs next (for example “Select one quad strip”) and how many faces are selected. The same two commands are also at the end of the UV menu (U in Edit Mode) as Validate UV Strip and Straighten UV Strip.
Click Validate Selection. It only checks the strip and changes nothing. On success the panel says “Strip is valid”; a refusal names the next step, for example “Deselect tris and ngons” or “Deselect one face to open it”.
Shape: Spacing (Uniform or Edge Length), Strip Axis (Auto, U or V) and Size (Keep UV Scale or Unit). Input: Selection (Auto, Mesh or UV) and Pinned UVs (Cancel or Move). The defaults suit most strips; Edge Length keeps long quads long, Unit makes the longer side exactly 1.0.
Click Straighten Strip. The strip's UVs become an axis-aligned rectangle; other islands, other UV maps, pin flags and the mesh itself stay as they were. The panel says “Strip straightened”. The Straighten UV Strip redo panel at the bottom left lets you change Spacing or Strip Axis without selecting again.
Ctrl+Z undoes the whole straighten in one step. Nothing is saved automatically: to keep the new UVs, save your .blend file (File › Save). The panel settings are stored in that .blend file too; the add-on writes nothing else to disk and uses no network.
Input: examples/skadira/curved-ribbon.blend: a fictional ribbon of 4 quads bent through 90 degrees, whose UVs follow the curve. All four faces are already selected.
Expected: Validate reports a valid strip: 4 quads, 5 cross-sections, uniform spacing, rectangle 0.7023 x 0.1000 UV, and nothing changes. Straighten Strip turns the curved UV arc into a straight rectangle of the same size with five evenly spaced cross-sections, inside the 0 to 1 UV square. The mesh does not move. Ctrl+Z brings the curve back.
The commands work only in Edit Mode on one mesh object; the tooltip then says “Enter Edit Mode on a mesh object first”. Also check that Skadira UV Strip Straighten is ticked in Preferences › Add-ons and that you are running Blender 4.5.x.
Nothing was changed. Select one open, connected strip of quads: deselect one face to open a ring, remove side branches, and deselect triangles and ngons. The panel's second line names the next step.
The strip contains pinned UVs and Pinned UVs is set to Cancel. Unpin them, or set Pinned UVs to Move: pinned UVs then move but keep their pin flag.
With Size set to Keep UV Scale, a strip that is longer than one UV unit extends past the 0 to 1 square. Set Size to Unit to make the longer side exactly 1.0, or move and scale the island yourself.
With UV sync selection off, Selection: Auto reads the UV Editor's selection. Select the same faces in the UV Editor, or set Selection to Mesh.
Neighbouring quads face opposite ways. Use Mesh › Normals › Recalculate Outside, then validate again.
Guide and examples: 30 September 2026. Examples are fictional or synthetic. Online guide · Support