backend-infra-engineer: Post v0.3.9-hotfix7 snapshot (build cleanup)

docs/internal/archive/handoffs/handoff-dungeon-rendering-session.md

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+# Handoff: Dungeon Object Rendering Investigation
+
+**Date**: 2025-11-26
+**Status**: Fixes applied, awaiting user testing verification
+**Plan File**: `/Users/scawful/.claude/plans/lexical-painting-tulip.md`
+
+---
+
+## Context
+
+User reported that dungeon object rendering "still doesn't look right" after previous fixes. Investigation revealed a palette index out-of-bounds bug and UI accessibility issues with the emulator preview.
+
+## Fixes Applied This Session
+
+### 1. Palette Index Clamping (`src/zelda3/dungeon/object_drawer.cc:1091-1099`)
+
+**Problem**: Tiles using palette indices 6-7 caused out-of-bounds color access.
+- Dungeon palettes have 90 colors = 6 sub-palettes × 15 colors each (indices 0-5)
+- SNES tilemaps allow palette 0-7, but palette 7 → offset 105 > 90 colors
+
+**Fix**:
+```cpp
+uint8_t pal = tile_info.palette_ & 0x07;
+if (pal > 5) {
+  pal = pal % 6;  // Wrap palettes 6,7 to 0,1
+}
+uint8_t palette_offset = pal * 15;
+```
+
+### 2. Emulator Preview UI Accessibility
+
+**Problem**: User said "emulator object render preview is difficult to access in the UI" - was buried in Object Editor → Preview tab → Enable checkbox.
+
+**Fix**: Added standalone card registration:
+- `src/app/editor/dungeon/dungeon_editor_v2.h`: Added `show_emulator_preview_` flag
+- `src/app/editor/dungeon/dungeon_editor_v2.cc`: Registered "SNES Object Preview" card (priority 65, shortcut Ctrl+Shift+V)
+- `src/app/gui/widgets/dungeon_object_emulator_preview.h`: Added `set_visible()` / `is_visible()` methods
+
+## Previous Fixes (Same Investigation)
+
+1. **Dirty flag bug** (`room.cc`): `graphics_dirty_` was cleared before use for floor/bg draw logic. Fixed with `was_graphics_dirty` capture pattern.
+
+2. **Incorrect floor mappings** (`object_drawer.cc`): Removed mappings for objects 0x0C3-0x0CA, 0x0DF to routine 19 (tile count mismatch).
+
+3. **BothBG routines** (`object_drawer.cc`): Routines 3, 9, 17, 18 now draw to both bg1 and bg2.
+
+## Files Modified
+
+```
+src/zelda3/dungeon/object_drawer.cc      # Palette clamping, BothBG fix, floor mappings
+src/zelda3/dungeon/room.cc               # Dirty flag bug fix
+src/app/editor/dungeon/dungeon_editor_v2.cc  # Emulator preview card registration
+src/app/editor/dungeon/dungeon_editor_v2.h   # show_emulator_preview_ flag
+src/app/gui/widgets/dungeon_object_emulator_preview.h  # Visibility methods
+```
+
+## Awaiting User Verification
+
+User explicitly stated: "Let's look deeper into this and not claim these phases are complete without me saying so"
+
+**Testing needed**:
+1. Do objects with palette 6-7 now render correctly?
+2. Is the "SNES Object Preview" card accessible from View menu?
+3. Does dungeon rendering look correct overall?
+
+## Related Documentation
+
+- Master plan: `docs/internal/plans/dungeon-object-rendering-master-plan.md`
+- Handler analysis: `docs/internal/alttp-object-handlers.md`
+- Phase plan: `/Users/scawful/.claude/plans/lexical-painting-tulip.md`
+
+## If Issues Persist
+
+Investigate these areas:
+1. **Graphics sheet loading** - Verify 8BPP data is being read correctly
+2. **Tile ID calculation** - Check if tile IDs are being parsed correctly from ROM
+3. **Object-to-routine mapping** - Many objects still unmapped (only ~24% coverage)
+4. **Draw routine implementations** - Some routines may have incorrect tile patterns
+
+## Build Status
+
+Build successful: `cmake --build build --target yaze -j8`