Dungeon graphics PNG interchange

A dungeon background sheet has eight raw color indices, 0–7. Its visible colors depend on the room palette, the entrance's main graphics group, and the slot where it is loaded. Some slots use colors 1–7 of a palette row; others use 9–15. Raw index 0 stays transparent in both cases.

Reorder source colors without changing selected artwork

1. Use Edit Graphics on a dungeon object or Overworld Tile16. The source supplies its actual palette row, half, graphics sheets, and entrance context.
2. Beside the Pixel Editor's color swatches, choose Reorder. Choose Current tile (the initial scope) or Source pattern (the source's resolved tiles). Click two colors in the After row to exchange slots.
3. Review the tile/color counts, then Apply. Cancel changes nothing. Slot 0 stays transparent. One Graphics Undo restores both colors and pixels.
4. Use Return to source to review the room/map, then File Save As. Palette and graphics saving must both be enabled in the project's save policy.

This changes the real palette slots and selected indexed pixels together; it is not a preview-palette adjustment. Other artwork sharing those palette slots or physical tiles can change. The operation does not clone resources or claim a complete game-wide usage census.

The operation supports loader-addressed, static 3bpp targets in dungeon and Overworld sources. Missing mappings, animated/HUD sources, conflicting selected mappings, stale entrance/sheet assignments, and foreign sessions are refused. Changing the source while the popup is open requires closing and reopening it. An older Palette-editor Undo/Redo that conflicts with this edit stays retained but unavailable until its expected colors are restored; undo the paired edit in Graphics first.

Headless product checks cover the actual control, one-step Undo/Redo, failed-save retention, and Save As/fresh reopen on disposable Oracle copies, including the custom wall-corner pattern in room $089. This is not whole-game visual or runtime qualification.

Export one sheet with its room colors

In Graphics → Sheet Browser → PNG export and import, select Room background slot, the room, and the palette row. The Loaded slot menu lists the slots that use the selected sheet. Choose the intended slot when it appears more than once. Export sheet PNG includes the sheet's unsaved pixel edits. Imports continue through preview, Apply import, undo, and the normal graphics save path.

When arriving through Edit Graphics from a source tile, Selected source tile reuses that target's supplied colors and entrance context directly. The manual room-slot mode resolves the saved room header and default entrance.

The corresponding CLI workflow is:

z3ed gfx-export --rom /path/to/base.sfc --sheet 0x12 \
  --palette room-slot:0xE6:2:2 --png /path/to/wall.png \
  --json /path/to/wall.json
z3ed gfx-import --rom /path/to/base.sfc --sheet 0x12 \
  --palette room-slot:0xE6:2:2 --png /path/to/wall.png --dry-run
z3ed gfx-import --rom /path/to/base.sfc --sheet 0x12 \
  --palette room-slot:0xE6:2:2 --png /path/to/wall.png \
  --write --out /path/to/edited.sfc

room-slot:<room>:<slot>:<row> uses destination slots 0–7 (tile ID / 64), not the reversed runtime upload counter. The command refuses a sheet that the requested slot does not load. Numbers are decimal unless prefixed with 0x or $. These example IDs describe Oracle's cave sheet; inspect another ROM's context instead of assuming it uses the same sheet.

The JSON records the physical sheet, roomset override, main group, entrance provenance, palette row and half, exact RGB colors, and raw-index-to-CGRAM mapping. An inferred default entrance describes the editor's reconstruction, not a proven gameplay route. The source sheet excludes animation overlays.

Keep PNGs indexed with values 0–7 for lossless interchange. RGB/RGBA import requires exact palette colors and does not quantize. When palette entries have identical RGB values, RGB pixels cannot distinguish those indices; indexed PNG retains that information. Pass --project-context /path/to/project.yaze on imports to apply the project's protected regions and graphics allocation policy. Writes use the existing sheet writer and refuse unsupported growth or protection conflicts.

Export the room's sheets

z3ed gfx-room-export --rom /path/to/base.sfc --room 0xE6 --row 2 \
  --out-dir /path/to/new-room-bundle

The parent folder must exist and the output directory must be new. Each supported slot gets its own PNG with raw indices 0–7 and the appropriate palette. manifest.json identifies each file and its matching gfx-import palette spec. Import an edited sheet with gfx-import; there is no bulk bundle import. Repeated sheet IDs are shared data, not independent assets. Unsupported 2bpp slots are explicitly marked and are not exported.

Existing room-bg:<room>:<row> explicitly selects the left half. The legacy 128×256 gfx-room-export --png and the panel's room PNG buttons apply one uniform palette to all slots. They remain compatible with earlier indexed files but do not represent every slot's displayed room colors. room-slot applies only to single-sheet interchange; use the bundle for per-slot colors across a room.