Island tools
The Island Tools panel lets you transform UV islands directly — stack, flip, straighten and select — without running a full pack. Every action is undo-safe.
Transform tools
- Stack / Unstack selected — stack identical or mirrored islands on top of each other right where they are (sharing texels), and spread them back out when you need to edit them.
- Flip X / Flip Y — mirror each selected island around its own center, so multiple islands flip in place rather than around a shared pivot.
- Straighten — snap tilted islands to their minimal bounding-box angle without moving them, so they sit axis-aligned.
- Rectify — flatten a curved quad-grid island (tube, pipe, strap, lathe/vase surface) into a straight rectangle, removing the curvature. It works on the island's open UV topology, so closed meshes like cylinders rectify cleanly. Islands that aren't a clean quad grid (round caps, triangulated parts) are skipped, not broken.
Smart selection
The Select section helps you build a selection quickly before transforming or packing:
- Select Similar — select islands that match the active one in shape.
- Select Flipped — find islands with negative (mirrored) UV winding.
- Select Border — select islands touching the UV space border.
- Invert — invert the current island selection.
You can then Pack Selected Islands to pack only the chosen subset, leaving the rest in place.
World-aligned UVs
These tools map UVs from the object's position in the 3D world — ideal for hard-surface and environment art:
- Project from World — box / triplanar projection from world space at your target texel density. Because the UVs come only from world position and density, the checker stays continuous across the whole model and any new geometry continues the existing islands when you reproject it. Works on the selected faces, or the whole object if none are selected.
- Orient to World — rotate each island so world up (+Z) points up (+V) in the UV, keeping directional textures (wood grain, gradients, trims) consistent across faces. Islands with no world-up direction in their plane (floors, ceilings) are skipped.
Checker map
Toggle a UV checker texture on the selected objects to inspect distortion and orientation, then toggle it off to restore your original materials. Choose the checker style:
- UV Grid — black-and-white checker for density and distortion.
- Color Grid — colored, numbered grid that reveals island orientation and mirrored (flipped) UVs — pair it with Orient to World.
When you enable it, the 3D viewports switch to show the texture (Solid shading → Color: Texture) so the checker is visible even when your material isn't set up for it. Turning it off restores your previous shading.
How selection works across Blender versions
The tools act on the island(s) you select in the UV Editor. On Blender 4.5 and earlier this reads your UV selection directly. On Blender 5.0+, per-UV selection isn't exposed to Python while editing, so TexelPack reads it on the fly — it works both with UV/mesh sync on (the 5.0 default, where the mesh selection drives) and with sync off (where your UV Editor selection drives). Either way the workflow is the same: select the island(s), then apply.
See Troubleshooting for more on Blender 5.0 selection behavior.