Authoring Custom Layouts

Custom layouts are experimental. Prefer the built-in layouts when they match your atlas, and subclass only for a genuinely missing convention.

A layout subclasses PentaTileLayout and implements three core methods:

@tool
class_name MyAlwaysFillLayout
extends PentaTileLayout

func is_dual_grid() -> bool:
    return false

func compute_mask(_coord: Vector2i, _sample_fn: Callable) -> int:
    return 1

func mask_to_atlas(_mask: int, _strip_index: int = 0) -> PentaTileAtlasSlot:
    var slot := PentaTileAtlasSlot.new()
    slot.atlas_coords = Vector2i(0, 0)
    return slot

Guidelines:

• Use _pack_alternative() when combining alternative tile ids with Godot transform flags.
• For single-grid layouts, mask=0 should usually render an atlas slot rather than erase the cell.
• Co-locate a bitmask_template PNG next to the layout script when you want inspector preview and fallback TileSet support.
• Keep custom layout logic small and table-driven where possible.