Region Neighbor Select

• type_id: region_neighbor_select
• category: Generate/Region/Select

Uses RegionMap adjacency to select regions that touch a specified ID, outside pixels, or an image edge. Region Adjacency outputs information, while this node outputs a RegionMap and mask that can flow into downstream processing.

Usage tips

• It excels at effects around a source. Select regions adjacent to a water ID to obtain a shoreline, or those next to lava to obtain scorched ground.
• Increasing depth expands the selection like ripples. Use it for concentric coloring such as two levels outward from a center.
• Use region_filter for simple conditions such as area or ID; use this node when the condition depends on what a region touches.

Related nodes

• region_filter — condition-based selection
• region_adjacency — numeric view of adjacency data
• region_fill — fills the selected result
• region_distance — surrounding effects based on distance rather than adjacency

Key parameters

TouchesOutside selects regions that actually touch OUTSIDE_ID. Use TouchesEdge when you specifically need regions touching the image edge.

How to use

To process only the area around a specified ID, start with mode = NeighborsOfId and depth = 1. Increase depth to expand through two or more levels of neighbors. Enable include_source only when the starting ID should also be selected.

The regions output is a RegionMap containing only the selected regions. Use mask as a regular image mask, or regions to continue Region processing.

When the input RegionMap wraps horizontally or vertically, adjacency also accounts for connections across those edges. This is useful for selecting neighbors across the seams of a tile asset.

Preview Seed changes only the region colors in the inspector preview. It does not affect the selected regions or mask.