Protect Areas

Some parts of a mesh matter more than the rest: a face, hands, text on a label. Protect Area keeps their detail while the rest gets crushed. It is in the Preserve box inside Advanced.

How to use it

  1. Select the object and press Tab for Edit Mode.
  2. Select the faces, edges or vertices you want to keep.
  3. Under Protect Area, click Add. The selection goes into a vertex group named Protected, and the field under the buttons shows it.
  4. Set Strength and Blur if the defaults don't suit you.
  5. Turn on Show Heatmap to check the result in the viewport.
  6. Click Crush.

To take parts back out, select them in Edit Mode and click Remove. Add and Remove only work in Edit Mode. Until an area is set, the panel shows a hint: "Edit Mode: select faces, then Add".

Using your own vertex group

You can also paint a vertex group yourself (Weight Paint mode, or assign weights in Edit Mode) and pick it in the field. When the active object is a mesh, the field lists its vertex groups. Higher weights keep more detail. With a group picked, Add puts the selection into that group.

Strength

Strength Effect
0% No protection
50% (default) Protected areas keep noticeably more detail
100% Protected areas are nearly frozen

The slider is not linear. The protection grows faster as you move towards 100%.

Blur

Protection fades out softly from the marked area instead of stopping at a hard line. Blur sets how far, as a share of the object's size. The default is 5%. 0% makes a hard edge.

Show Heatmap

Colors the selected objects in the viewport by how strongly each part is protected, with the Blur fade included: blue is free to crush, red is fully protected. It updates as you add, remove or change Blur, including in Edit Mode. It is only a viewport overlay; nothing is added to your scene.

Strength and Blur are greyed out until a Protect Area is set.

Good to know

  • The group is read after modifiers, so it matches the mesh you see in the viewport.
  • The group name is matched on every selected object. Objects that do not have a group with that name are crushed normally.
  • If the group exists but has no weights, the object is crushed without protection and Blender shows a warning.
  • Protect Area works with all three target modes.
  • Strong protection on large areas can leave the result above the target triangle count. Check the after count in the report. See Limits.