v1.2.1-rp2040 \u2014 castling visual hint
Pre-release
Patch release
Adds a clear visual walkthrough for the castle move that previously required the user to know FIDE rules ("now move the rook too"). Also bundles in some source code that was only on my workspace machine and missing from the previous v1.0..v1.2 git tags.
What's new
When you complete a kingside (king to g-file) or queenside (king to c-file) castle in Human-vs-Human mode, the board now:
- Flashes the rook source square in blinking blue (4x) — tells you which rook to lift.
- Lights the rook destination square in solid blue — tells you where to put it.
- Holds both lit for 2 seconds so a slow user catches the hint.
- Logs
Castling: move the rook from h1 to f1(or appropriate squares) to serial.
Known limitation
Castling visual hint is Human-vs-Human only for now. AI mode (chess_bot::executeBotMove) still does direct board mutation instead of going through ChessEngine::applyMove, so:
- The hint isn't drawn in AI mode
- The bot's castles also leave the rook on its original square (king moves but rook stays put — invalid state)
Both will be fixed in v1.3 by refactoring chess_bot.cpp to use applyMove (which will also fix the row-axis serial print mirror in one pass).
Verified
Sketch uses 148801 bytes (0%) of program storage space.
Global variables use 44640 bytes (16%) of dynamic memory.
=== Self-tests complete: 10/10 passed ===
How to flash
Drag-and-drop OpenChess-v1.2.1-rp2040.uf2 onto the RPI-RP2 USB drive after double-tapping the white reset button.