Overview
An advanced boundary node that extracts RegionMap boundaries as line data
(PixelLine). Unlike region_border, which produces a quick line image, this node
can precisely select which IDs define a boundary and clean protrusions to improve
the quality of the resulting pixel lines.
- Category: Generate / Region / Render
- Uses: processing boundaries downstream, extracting only a specific region pair's boundary, and cleaning boundaries as pixel lines
Usage tips
- Use
region_borderto quickly overlay lines. Use this node when you need only the boundary between particular regions or plan to process the lines downstream. Pairselection is its unique strength. It can isolate the water/sand boundary, for example, to create a white wave line.- Corner cleanup with
SafeorStrongproduces cleaner one-pixel lines for pixel art.
Related nodes
region_border— convenient image versionregion_fill— base image beneath the linesregion_remap— stabilizes ID selection beforehand
Target
| Value | Description |
|---|---|
All |
Extract all region boundaries |
RegionId |
Extract only boundaries touching the specified ID |
IdRange |
Extract only boundaries touching the specified ID range |
Pair |
Extract only the boundary between the specified two regions |
ID range condition
| Value | Description |
|---|---|
BothInside |
Extract only boundaries where both region IDs are in range |
Touching |
Extract boundaries where either region ID is in range |
Crossing |
Extract only boundaries between an in-range and out-of-range region |
Placement
| Value | Description |
|---|---|
BothSides |
Extract both sides of the boundary |
ForwardSide |
Extract only one side, based on the right/down direction |
LowerIdSide |
Extract only the side belonging to the lower region ID |
HigherIdSide |
Extract only the side belonging to the higher region ID |
Corner cleanup modes
| Value | Description |
|---|---|
Safe |
Protects 2x2-or-larger blocks and branches, conservatively removing only short protrusions attached to thick boundaries |
Strong |
Uses Protrusion Length to remove somewhat longer short protrusions; protects blocks, branches, and centers connected in all four directions |
Horizontal |
Follows the behavior of RemoveHorizontal in Path Stroke |
Vertical |
Follows the behavior of RemoveVertical in Path Stroke |
How to use
Connect Region Cells.regions -> Region Boundary Trace.regions.
Use Region Border when you need an image immediately. Use this node when you want line data for further processing or need to isolate a specific region pair.
When the input RegionMap has horizontal or vertical wrapping, contacts across the left/right or top/bottom edges are also extracted as boundaries. Boundaries at the seams of a tile asset remain part of the same PixelLine data.
cleanup_corners does not force blocks two or more pixels wide into thin lines. It
is an aid for removing short protrusions and isolated-looking noise that stand out
in pixel art. Turn it off to preserve thick boundaries, use Safe to remove only
fine whiskers, and use Strong for more aggressive cleanup.