refactored to multiple games implementation

CMakeLists.txt

@@ -41,6 +41,8 @@ pico_sdk_init()
 
 add_executable(basic1 
     basic1.cpp 
+    lib/input_manager.cpp
+    games/tic_tac_toe.cpp
     lib/st7796/st7796.c 
     lib/ft6336u/ft6336u.c 
     lib/sd_card/sd_card.c 
@@ -75,6 +77,8 @@ target_link_libraries(basic1
 # Add the standard include files to the build
 target_include_directories(basic1 PRIVATE
     ${CMAKE_CURRENT_LIST_DIR}
+    ${CMAKE_CURRENT_LIST_DIR}/games
+    ${CMAKE_CURRENT_LIST_DIR}/lib
     ${CMAKE_CURRENT_LIST_DIR}/lib/fatfs/source
     ${CMAKE_CURRENT_LIST_DIR}/lib/st7796
     ${CMAKE_CURRENT_LIST_DIR}/lib/ft6336u

MultigameRefactorPlan.md

@@ -0,0 +1,155 @@
+Multigame Migration Plan
+Overview
+Refactor the existing monolithic tic-tac-toe implementation into a modular game architecture that allows multiple games to run on the RP2350 platform while preserving the interrupt-driven, dual-core reactive architecture.
+
+Goals
+Abstract game logic from hardware/display management
+Create reusable input processing system
+Enable multiple games to coexist in the codebase
+Maintain the efficient reactive architecture (event-driven, dual-core)
+Keep hardware-specific code isolated in basic1.cpp
+Architecture Components
+1. Input Event System
+Files: lib/input_event.h
+
+Defines shared input event structures used by both InputManager and Game classes:
+
+InputType enum (NONE, TOUCH_DOWN, TOUCH_MOVE, TOUCH_UP, BUTTON_0, BUTTON_1, GESTURE)
+InputEvent struct with coordinates, gesture codes, button IDs, pressure, validity flag
+2. Input Manager
+Files: lib/input_manager.h, lib/input_manager.cpp
+
+Handles all input processing and debouncing:
+
+Constructor: InputManager(LowLevelTouch* touch, GameConfig* config)
+Methods: process_touch_input(uint32_t* last_time), process_button_input()
+Returns InputEvent objects to be passed to games
+Manages touch debouncing and gesture recognition
+Does NOT handle button GPIO setup (stays in basic1.cpp)
+3. Abstract Game Base Class
+Files: lib/game.h
+
+Defines the interface all games must implement:
+
+Constructor: Game(uint16_t width, uint16_t height, LowLevelRenderer* renderer, LowLevelGUI* gui)
+Protected members: width, height, renderer, gui
+Pure virtual methods:
+virtual void init() = 0 - Initialize game state
+virtual bool update(const InputEvent& event) = 0 - Process input, return true if redraw needed
+virtual void draw() = 0 - Render game to buffer
+Virtual destructor: virtual ~Game() {}
+4. Tic-Tac-Toe Game Implementation
+Files: games/tic_tac_toe.h, games/tic_tac_toe.cpp
+
+Concrete implementation of the Game interface:
+
+Private GameState struct with board, current player, winner, statistics
+Private method: check_winner()
+Private constants: BOARD_SIZE, CELL_SIZE, BOARD_Y, LINE_WIDTH
+Overrides: init(), update(const InputEvent& event), draw()
+Encapsulates all tic-tac-toe logic extracted from basic1.cpp lines 162-770
+5. Main Loop Refactor
+File: basic1.cpp
+
+Simplified main program focusing on hardware management:
+
+Keep: Display initialization, dual-core setup, interrupt handlers, GPIO configuration
+Remove: Game-specific logic (moves to TicTacToeGame)
+Add: InputManager instantiation, Game* pointer instantiation
+Modify main loop:
+Migration Steps
+Step 1: Create Input Event Header
+Extract input structures from basic1.cpp (lines 134-156) to new file lib/input_event.h.
+
+Validation:
+
+Compile successfully
+No duplicate definitions
+Both basic1.cpp and new files include this header
+Step 2: Create Input Manager
+Move input processing functions (lines 313-442) to new InputManager class.
+
+Validation:
+
+Constructor properly stores touch pointer and config
+process_touch_input() returns valid InputEvent on touch
+process_button_input() returns valid InputEvent on button press
+Debouncing still works correctly
+Compile and run - verify touch/button detection unchanged
+Step 3: Create Abstract Game Class
+Create lib/game.h with base class definition.
+
+Validation:
+
+Header compiles successfully
+Pure virtual methods defined correctly
+Protected members accessible to derived classes
+Step 4: Extract Tic-Tac-Toe Game
+Create TicTacToeGame class inheriting from Game.
+
+Validation:
+
+Move GameState struct (lines 162-176) - verify all members present
+Move check_winner() (lines 447-495) - verify logic identical
+Move game_init() to init() override (lines 505-522)
+Move game_update() to update() override (lines 536-668)
+Move game_draw() to draw() override (lines 671-770)
+Move constants: BOARD_SIZE, CELL_SIZE, BOARD_Y
+Compile successfully
+Step 5: Refactor Main Loop
+Update basic1.cpp to use new architecture.
+
+Validation:
+
+Remove old GameState state variable
+Remove old game functions
+Instantiate InputManager after hardware init
+Instantiate TicTacToeGame as Game*
+Update main loop to use polymorphic calls
+Compile successfully
+Run and verify: Touch input works, buttons work, game plays correctly
+Verify dual-core refresh still works (Core 1 handles display)
+Test full game: place pieces, win conditions, restart
+Step 6: Update Build System
+Modify CMakeLists.txt to include new source files.
+
+Validation:
+
+Add lib/input_manager.cpp
+Add games/tic_tac_toe.cpp
+Clean build succeeds
+Binary size reasonable (no major bloat)
+Step 7: Final Testing
+Comprehensive system test.
+
+Validation:
+
+Touch detection works (tap cells)
+Button navigation works (KEY0/KEY1)
+Game logic correct (wins, ties, restart)
+Display refreshes properly (no artifacts)
+Statistics persist across games
+Debug output shows correct events
+System remains responsive during e-ink refresh
+Future Extensions
+Adding New Games
+To add a new game (e.g., Snake, Pong):
+
+Create games/snake.h and games/snake.cpp
+Inherit from Game base class
+Implement init(), update(), draw()
+Define game-specific state as private members
+Add to CMakeLists.txt
+Change game selection in basic1.cpp: Game* current_game = new SnakeGame(...)
+Game Launcher (Future)
+Create GameLauncher class to display menu
+Allow runtime game switching
+Handle cleanup: delete current_game; current_game = new SnakeGame(...)
+Store game selection preference in flash
+Key Design Principles
+Hardware Isolation: All GPIO, interrupts, hardware config stay in basic1.cpp
+State Encapsulation: Each game owns its state completely
+Polymorphism: Use Game* pointer for runtime flexibility
+Event-Driven: Games respond to InputEvent objects only
+Reactive Rendering: Only redraw when update() returns true
+Dual-Core Efficiency: Core 0 handles logic, Core 1 handles display refresh

TESTING_CHECKLIST.md

@@ -0,0 +1,321 @@
+# Step 7: Final Testing Checklist
+## Refactored Tic-Tac-Toe Game - Hardware Validation
+
+**Date:** January 30, 2026  
+**Status:** Compilation successful ✓
+
+---
+
+## Pre-Test Verification
+
+### Build Artifacts
+- [x] Compiles without errors
+- [x] Compiles without warnings
+- [x] basic1.uf2 generated successfully
+- [x] All new modules included in build
+
+### Architecture Components
+- [x] InputManager class (lib/input_manager.cpp)
+- [x] Game base class (lib/game.h)
+- [x] TicTacToeGame class (games/tic_tac_toe.cpp)
+- [x] Input events (lib/input_event.h)
+- [x] Main loop refactored (basic1.cpp)
+
+---
+
+## Hardware Testing Plan
+
+### Test 1: Basic System Startup
+**Expected Behavior:**
+- USB serial connection establishes
+- Debug messages appear:
+  - "=== [BOARD_NAME] Demo ==="
+  - "Core 1 started - handling display refreshes"
+  - "Touch initialized successfully"
+  - Initial game board renders
+
+**Validation:**
+- [ ] Serial output shows startup messages
+- [ ] Both cores start successfully
+- [ ] Display shows Tic-Tac-Toe board
+- [ ] No system hangs or crashes
+
+---
+
+### Test 2: Touch Input Detection
+**Test Steps:**
+1. Tap empty cell in top-left corner
+2. Tap empty cell in center
+3. Tap empty cell in bottom-right corner
+4. Tap already occupied cell
+5. Tap outside board area
+
+**Expected Behavior:**
+- Debug output: "Processing touch: flag=1"
+- Debug output: "Touch DOWN at (x,y)"
+- X or O appears in tapped cell
+- Occupied cells reject new pieces
+- Touches outside board are ignored
+- Turn indicator updates on left side
+
+**Validation:**
+- [ ] Touch interrupts fire correctly
+- [ ] Coordinates map to correct cells
+- [ ] Pieces appear in touched cells
+- [ ] Turn switches between X and O
+- [ ] Invalid moves rejected
+- [ ] Debug messages show correct coordinates
+
+---
+
+### Test 3: Button Navigation (e-ink boards)
+**Test Steps:**
+1. Press KEY0 to move selection
+2. Press KEY0 multiple times to cycle cells
+3. Press KEY1 to place piece in selected cell
+4. Verify selection skips occupied cells
+
+**Expected Behavior:**
+- KEY0: Selection highlight moves to next cell
+- KEY1: Piece placed at highlighted cell
+- Selection automatically skips occupied cells
+- Debug output: "Selection moved to [row,col]"
+
+**Validation:**
+- [ ] KEY0 moves selection correctly
+- [ ] KEY1 places piece at selection
+- [ ] Selection visual feedback works
+- [ ] Button debouncing functions
+- [ ] Debug messages show correct events
+
+---
+
+### Test 4: Win Condition Detection
+**Test Scenarios:**
+
+#### Row Win (X)
+- Tap cells: [0,0], [1,0], [0,1], [1,1], [0,2]
+- Expected: "X WINS!" message
+
+#### Column Win (O)
+- Tap cells: [0,0], [0,1], [1,0], [0,2], [2,1], [0,3]
+- Expected: "O WINS!" message (after X's move)
+
+#### Diagonal Win (X)
+- Tap cells: [0,0], [0,1], [1,1], [0,2], [2,2]
+- Expected: "X WINS!" message
+
+#### Tie Game
+- Fill all cells with no winner
+- Expected: "TIE GAME!" message
+
+**Validation:**
+- [ ] Row wins detected correctly
+- [ ] Column wins detected correctly
+- [ ] Diagonal wins detected correctly
+- [ ] Tie games detected correctly
+- [ ] Game over message displays
+- [ ] No further moves accepted after win
+
+---
+
+### Test 5: Game Restart
+**Test Steps:**
+1. Complete a game (win or tie)
+2. Touch screen or press KEY0
+3. Verify board clears
+4. Verify X starts first
+5. Play another game
+
+**Expected Behavior:**
+- Board clears to empty state
+- X always starts after restart
+- Turn indicator resets
+- Previous game statistics preserved
+- New game begins immediately
+
+**Validation:**
+- [ ] Touch restarts game
+- [ ] KEY0 restarts game
+- [ ] Board completely clears
+- [ ] X starts correctly
+- [ ] Game flows normally after restart
+
+---
+
+### Test 6: Statistics Tracking
+**Test Steps:**
+1. Play game where X wins
+2. Check statistics: "X:1 O:0 Tie:0"
+3. Restart and let O win
+4. Check statistics: "X:1 O:1 Tie:0"
+5. Play to tie
+6. Check statistics: "X:1 O:1 Tie:1"
+7. Verify move counter increments
+
+**Expected Behavior:**
+- Win counts persist across restarts
+- Tie count tracks correctly
+- Move counter shows total moves
+- Statistics display at bottom
+
+**Validation:**
+- [ ] X wins increment correctly
+- [ ] O wins increment correctly
+- [ ] Ties increment correctly
+- [ ] Move counter accurate
+- [ ] Stats persist across restarts
+- [ ] Display shows current stats
+
+---
+
+### Test 7: Display Refresh (Dual-Core)
+**Test Steps:**
+1. Make move and observe refresh
+2. Make rapid successive moves
+3. During e-ink refresh, attempt another move
+4. Verify Core 0 stays responsive
+
+**Expected Behavior:**
+- Display refreshes after each move
+- Core 1 handles refresh asynchronously
+- Core 0 processes inputs during refresh
+- Pending refresh queues if Core 1 busy
+- Debug message: "Refresh pending - Core 1 still busy" (if applicable)
+
+**Validation:**
+- [ ] Display updates after moves
+- [ ] No screen artifacts
+- [ ] System responsive during refresh
+- [ ] E-ink refresh completes fully
+- [ ] Dual-core architecture working
+- [ ] No refresh race conditions
+
+---
+
+### Test 8: Edge Cases & Error Handling
+**Test Scenarios:**
+
+#### Rapid Touch Events
+- Tap multiple cells rapidly
+- Expected: All valid moves registered
+
+#### Touch During Transition
+- Touch during display refresh
+- Expected: Input queued, processed after refresh
+
+#### Multiple Button Presses
+- Press both KEY0 and KEY1 simultaneously
+- Expected: One action processed (KEY0 priority)
+
+#### Touch Release Events
+- Touch and hold, then release
+- Expected: Debug shows "Touch UP"
+
+**Validation:**
+- [ ] Rapid touches handled correctly
+- [ ] No missed inputs
+- [ ] No duplicate moves
+- [ ] Touch up events processed
+- [ ] System remains stable
+
+---
+
+### Test 9: Memory & Performance
+**Observations:**
+- Monitor for memory leaks (play 10+ games)
+- Check for display artifacts over time
+- Verify system doesn't slow down
+- Confirm no crashes after extended use
+
+**Validation:**
+- [ ] No memory leaks observed
+- [ ] Consistent performance over time
+- [ ] No progressive slowdown
+- [ ] Display quality maintained
+- [ ] System stable after 10+ games
+
+---
+
+### Test 10: Code Architecture Validation
+**Verification:**
+- InputManager handles all input processing
+- TicTacToeGame encapsulates game logic
+- basic1.cpp only handles hardware/main loop
+- Polymorphic Game pointer works correctly
+- All extern variables resolve correctly
+
+**Validation:**
+- [ ] InputManager processes touch correctly
+- [ ] InputManager processes buttons correctly
+- [ ] Game class polymorphism works
+- [ ] Clean separation of concerns
+- [ ] No tight coupling between modules
+
+---
+
+## Success Criteria
+
+### Must Pass (Critical)
+1. System boots and initializes
+2. Touch input registers moves
+3. Win conditions detect correctly
+4. Game restarts properly
+5. Display refreshes without artifacts
+
+### Should Pass (Important)
+1. Button navigation works (if board has buttons)
+2. Statistics track accurately
+3. Debug output shows correct events
+4. Dual-core refresh is non-blocking
+5. Edge cases handled gracefully
+
+### Nice to Have (Enhancement)
+1. Gesture recognition works
+2. No performance degradation over time
+3. Clean debug output formatting
+4. Smooth user experience
+
+---
+
+## Issue Tracking
+
+### Found Issues
+| Issue | Severity | Description | Status |
+|-------|----------|-------------|--------|
+|       |          |             |        |
+
+### Notes
+- 
+-
+-
+
+---
+
+## Test Results Summary
+
+**Date Tested:** _________________  
+**Tester:** _________________  
+**Hardware:** _________________  
+
+**Overall Status:** ⬜ PASS / ⬜ FAIL / ⬜ PARTIAL
+
+**Critical Issues:** _________________
+
+**Recommendations:** _________________
+
+---
+
+## Next Steps
+
+If all tests pass:
+- ✅ Architecture successfully refactored
+- ✅ Ready to add new games (Snake, Pong, etc.)
+- ✅ Can implement GameLauncher for game selection
+
+If issues found:
+1. Document specific failing test
+2. Check relevant module (InputManager, TicTacToeGame, or main loop)
+3. Verify hardware connections (touch INT pin, button pins)
+4. Review debug serial output for clues
+5. Test with minimal configuration first

basic1.cpp

@@ -44,10 +44,12 @@
 #include <stdio.h>
 #include <string.h>
 #include "display/low_level_render.h"
-#include "display/low_level_gui.h"
 #include "display/low_level_display.h"
 #include "display/low_level_display_epaper.h"
 #include "display/low_level_touch.h"
+#include "input_manager.h"
+#include "game.h"
+#include "tic_tac_toe.h"
 
 
 // Binary info for RP2350 - ensures proper boot image structure
@@ -130,52 +132,9 @@ bool is_refresh_in_progress() {
 }
 
 // ============================================================================
-// INPUT EVENT STRUCTURES
+// GAME CONFIGURATION
 // ============================================================================
 
-// Input event types
-enum InputType {
-    INPUT_NONE = 0,
-    INPUT_TOUCH_DOWN,
-    INPUT_TOUCH_MOVE,
-    INPUT_TOUCH_UP,
-    INPUT_BUTTON_0,
-    INPUT_BUTTON_1,
-    INPUT_GESTURE
-};
-
-// Unified input event structure
-struct InputEvent {
-    InputType type;
-    int16_t x;
-    int16_t y;
-    uint8_t gesture_code;  // For gesture events
-    uint8_t button_id;     // For button events
-    uint8_t pressure;      // Touch pressure/weight
-    bool valid;            // Set to true if event is valid
-};
-
-// ============================================================================
-// GAME STATE AND CONFIGURATION
-// ============================================================================
-
-// Game state - customize this for your game
-struct GameState {
-    // Tic-Tac-Toe game state
-    uint8_t board[3][3];     // 0=empty, 1=X, 2=O
-    uint8_t current_player;  // 1=X, 2=O
-    uint8_t winner;          // 0=none, 1=X wins, 2=O wins, 3=tie
-    uint8_t selected_row;    // Currently selected cell
-    uint8_t selected_col;
-    bool game_over;
-    
-    // Game statistics
-    uint32_t x_wins;
-    uint32_t o_wins;
-    uint32_t ties;
-    uint32_t total_moves;
-};
-
 // Game configuration - adjust these for your game
 struct GameConfig {
     uint32_t touch_debounce_ms;    // Touch polling rate
@@ -282,488 +241,9 @@ void refresh_screen(const uint8_t *buffer, LowLevelDisplay* display) {
 // INPUT PROCESSING
 // ============================================================================
 
-/**
- * @brief Get human-readable gesture name
- * 
- * @param gesture_code Gesture code from touch controller
- * @return Constant string with gesture name
- */
-const char* get_gesture_name(uint8_t gesture_code) {
-    switch(gesture_code) {
-        case 0x10: return "Move Up";
-        case 0x14: return "Move Right";
-        case 0x18: return "Move Down";
-        case 0x1C: return "Move Left";
-        case 0x48: return "Zoom In";
-        case 0x49: return "Zoom Out";
-        default: return "Unknown";
-    }
-}
 
-/**
- * @brief Process touch input and convert to InputEvent
- * 
- * Reads touch data from controller and creates appropriate InputEvent.
- * Handles debouncing and filtering internally.
- * 
- * @param config Game configuration
- * @param last_time Pointer to last touch time for debouncing
- * @return InputEvent structure (valid=false if no valid input)
- */
-InputEvent process_touch_input(const GameConfig& config, uint32_t* last_time) {
-    InputEvent event = {INPUT_NONE, 0, 0, 0, 0, 0, false};
-    
-    // Check if touch interrupt flag is set
-    if (!touch_interrupt_flag) {
-        return event;  // No touch event
-    }
-    
-    printf("Processing touch: flag=%d, event_down=%d\n", touch_interrupt_flag, touch_event_down);
-    
-    // Don't clear the flag yet - we may still be processing continuous touch
-    
-    // Check if touch is active
-    if (!touch_event_down) {
-        // Touch released - reset timing for next touch
-        touch_interrupt_flag = false;
-        *last_time = 0;  // Reset so next touch is treated as new touch-down
-        event.type = INPUT_TOUCH_UP;
-        event.valid = true;
-        printf("Touch UP\n");
-        return event;
-    }
-    
-    // Touch is down - check debounce timing
-    uint32_t now = to_ms_since_boot(get_absolute_time());
-    if (now - *last_time < config.touch_debounce_ms) {
-        return event;  // Too soon, skip
-    }
-    
-    // Read touch data
-    TouchData touch_data;
-    if (!touch || !touch->read_touch(&touch_data)) {
-        // Clear flag even if read failed to prevent getting stuck
-        touch_interrupt_flag = false;
-        printf("Touch read FAILED\n");
-        return event;  // Read failed
-    }
-    
-    // Clear the interrupt flag after successfully reading touch data
-    // This allows the next touch interrupt to be detected
-    touch_interrupt_flag = false;
-    
-    printf("Touch DOWN at (%d,%d)\n", touch_data.points[0].x, touch_data.points[0].y);
-    
-    // Populate event structure
-    event.x = touch_data.points[0].x;
-    event.y = touch_data.points[0].y;
-    event.pressure = touch_data.points[0].pressure;
-    event.gesture_code = touch_data.gesture;
-    event.valid = true;
-    
-    // Determine event type
-    if (*last_time == 0) {
-        event.type = INPUT_TOUCH_DOWN;
-    } else {
-        event.type = INPUT_TOUCH_MOVE;
-    }
-    
-    // Handle gesture events
-    if (config.enable_gestures && touch_data.gesture != 0) {
-        event.type = INPUT_GESTURE;
-        if (config.debug_verbose) {
-            printf("Gesture: 0x%02X (%s)\n", event.gesture_code, get_gesture_name(event.gesture_code));
-        }
-    }
-    
-    *last_time = now;
-    return event;
-}
 
-/**
- * @brief Process button input and convert to InputEvent
- * 
- * Checks button flags and verifies button state with debouncing.
- * Clears flags after processing.
- * 
- * @param config Game configuration
- * @return InputEvent structure (valid=false if no valid input)
- */
-InputEvent process_button_input(const GameConfig& config) {
-    InputEvent event = {INPUT_NONE, 0, 0, 0, 0, 0, false};
-    
-#ifdef BUTTON_KEY0_PIN
-    // Check KEY0
-    if (button_key0_pressed) {
-        button_key0_pressed = false;
-        sleep_ms(config.button_debounce_ms);
-        
-        if (gpio_get(BUTTON_KEY0_PIN) == 0) {  // Verify still pressed
-            event.type = INPUT_BUTTON_0;
-            event.button_id = 0;
-            event.valid = true;
-            
-            if (config.debug_verbose) {
-                printf("Button KEY0 action triggered\n");
-            }
-            return event;
-        }
-    }
-    
-#ifdef BUTTON_KEY1_PIN
-    // Check KEY1
-    if (button_key1_pressed) {
-        button_key1_pressed = false;
-        sleep_ms(config.button_debounce_ms);
-        
-        if (gpio_get(BUTTON_KEY1_PIN) == 0) {  // Verify still pressed
-            event.type = INPUT_BUTTON_1;
-            event.button_id = 1;
-            event.valid = true;
-            
-            if (config.debug_verbose) {
-                printf("Button KEY1 action triggered\n");
-            }
-            return event;
-        }
-    }
-#endif
-#endif
-    
-    return event;
-}
 
-// ============================================================================
-// GAME LOGIC (Customize this section for your game!)
-// ============================================================================
-
-// Game board dimensions (used for both drawing and touch detection)
-const int BOARD_SIZE = 200;
-const int CELL_SIZE = BOARD_SIZE / 3;
-const int BOARD_Y = 80;  // Y position below title
-
-/**
- * @brief Check if there's a winner on the board
- * @return 0=no winner, 1=X wins, 2=O wins, 3=tie
- */
-uint8_t check_winner(const GameState* state) {
-    // Check rows
-    for (int row = 0; row < 3; row++) {
-        if (state->board[row][0] != 0 && 
-            state->board[row][0] == state->board[row][1] && 
-            state->board[row][1] == state->board[row][2]) {
-            return state->board[row][0];
-        }
-    }
-    
-    // Check columns
-    for (int col = 0; col < 3; col++) {
-        if (state->board[0][col] != 0 && 
-            state->board[0][col] == state->board[1][col] && 
-            state->board[1][col] == state->board[2][col]) {
-            return state->board[0][col];
-        }
-    }
-    
-    // Check diagonals
-    if (state->board[0][0] != 0 && 
-        state->board[0][0] == state->board[1][1] && 
-        state->board[1][1] == state->board[2][2]) {
-        return state->board[0][0];
-    }
-    
-    if (state->board[0][2] != 0 && 
-        state->board[0][2] == state->board[1][1] && 
-        state->board[1][1] == state->board[2][0]) {
-        return state->board[0][2];
-    }
-    
-    // Check for tie (board full)
-    bool board_full = true;
-    for (int row = 0; row < 3; row++) {
-        for (int col = 0; col < 3; col++) {
-            if (state->board[row][col] == 0) {
-                board_full = false;
-                break;
-            }
-        }
-        if (!board_full) break;
-    }
-    
-    if (board_full) return 3; // Tie
-    return 0; // No winner yet
-}
-
-/**
- * @brief Initialize game state
- * 
- * Called once at startup to set initial game values.
- * Customize this for your game.
- * 
- * @param state Pointer to GameState to initialize
- */
-void game_init(GameState* state) {
-    // Clear the board
-    for (int row = 0; row < 3; row++) {
-        for (int col = 0; col < 3; col++) {
-            state->board[row][col] = 0;
-        }
-    }
-    
-    state->current_player = 1;  // X starts
-    state->winner = 0;
-    state->selected_row = 1;    // Start in center
-    state->selected_col = 1;
-    state->game_over = false;
-    state->total_moves = 0;
-    
-    // Keep win statistics across games
-    // state->x_wins, state->o_wins, state->ties remain unchanged
-}
-
-/**
- * @brief Update game state based on input event
- * 
- * This is where your game logic goes.
- * Called whenever an input event occurs.
- * 
- * @param state Pointer to GameState to update
- * @param input Input event to process
- * @param config Game configuration
- * @param renderer Renderer for drawing operations
- * @return true if screen needs refresh (drawing occurred)
- */
-bool game_update(GameState* state, const InputEvent& input, const GameConfig& config, LowLevelRenderer* renderer) {
-    bool needs_refresh = false;
-    
-    switch (input.type) {
-        case INPUT_TOUCH_DOWN: {
-            // If game is over, restart on touch
-            if (state->game_over) {
-                game_init(state);
-                needs_refresh = true;
-                break;
-            }
-
-            printf("Touch down at (%d,%d)\n", input.x, input.y);
-            
-            // Calculate board position (must match game_draw!)
-            int board_x = V_WIDTH - BOARD_SIZE - 20;
-            
-            // Check if touch is within board
-            if (input.x >= board_x && input.x < board_x + BOARD_SIZE &&
-                input.y >= BOARD_Y && input.y < BOARD_Y + BOARD_SIZE) {
-                
-                int touched_col = (input.x - board_x) / CELL_SIZE;
-                int touched_row = (input.y - BOARD_Y) / CELL_SIZE;
-                
-                // Clamp to valid range (safety check)
-                if (touched_row >= 0 && touched_row < 3 && touched_col >= 0 && touched_col < 3) {
-                    // Place piece if cell is empty
-                    if (state->board[touched_row][touched_col] == 0) {
-                        state->board[touched_row][touched_col] = state->current_player;
-                        state->total_moves++;
-                        
-                        // Check for winner
-                        state->winner = check_winner(state);
-                        if (state->winner != 0) {
-                            state->game_over = true;
-                            if (state->winner == 1) state->x_wins++;
-                            else if (state->winner == 2) state->o_wins++;
-                            else if (state->winner == 3) state->ties++;
-                        } else {
-                            // Switch player
-                            state->current_player = (state->current_player == 1) ? 2 : 1;
-                        }
-                        
-                        needs_refresh = true;
-                        
-                        if (config.debug_verbose) {
-                            printf("Touch at [%d,%d] (pixel %d,%d) by player %d\n", 
-                                   touched_row, touched_col, input.x, input.y,
-                                   state->current_player == 1 ? 2 : 1);
-                        }
-                    } else if (config.debug_verbose) {
-                        printf("Cell [%d,%d] already occupied\n", touched_row, touched_col);
-                    }
-                }
-            } else if (config.debug_verbose) {
-                printf("Touch outside board: %d,%d\n", input.x, input.y);
-            }
-            break;
-        }
-            
-        case INPUT_BUTTON_0:
-            // KEY0: Move selection (for button-only boards)
-            if (!state->game_over) {
-                // Move to next cell, skipping occupied ones
-                int attempts = 0;
-                do {
-                    state->selected_col++;
-                    if (state->selected_col > 2) {
-                        state->selected_col = 0;
-                        state->selected_row++;
-                        if (state->selected_row > 2) {
-                            state->selected_row = 0;
-                        }
-                    }
-                    attempts++;
-                    // If we've tried all 9 cells, stop (game might be full)
-                    if (attempts >= 9) break;
-                } while (state->board[state->selected_row][state->selected_col] != 0);
-                
-                needs_refresh = true;
-                if (config.debug_verbose) {
-                    printf("Selection moved to [%d,%d]\n", state->selected_row, state->selected_col);
-                }
-            } else {
-                // Restart game
-                game_init(state);
-                needs_refresh = true;
-            }
-            break;
-            
-        case INPUT_BUTTON_1:
-            // KEY1: Place piece at selected position
-            if (!state->game_over) {
-                if (state->board[state->selected_row][state->selected_col] == 0) {
-                    state->board[state->selected_row][state->selected_col] = state->current_player;
-                    state->total_moves++;
-                    
-                    // Check for winner
-                    state->winner = check_winner(state);
-                    if (state->winner != 0) {
-                        state->game_over = true;
-                        if (state->winner == 1) state->x_wins++;
-                        else if (state->winner == 2) state->o_wins++;
-                        else if (state->winner == 3) state->ties++;
-                    } else {
-                        // Switch player
-                        state->current_player = (state->current_player == 1) ? 2 : 1;
-                    }
-                    
-                    needs_refresh = true;
-                    
-                    if (config.debug_verbose) {
-                        printf("Piece placed at [%d,%d]\n", state->selected_row, state->selected_col);
-                    }
-                }
-            }
-            break;
-            
-        default:
-            break;
-    }
-    
-    return needs_refresh;
-}
-
-/**
- * @brief Draw game graphics to screen buffer
- * 
- * All initial UI drawing operations go here.
- * Called once at startup to create the initial screen.
- * 
- * @param state Pointer to current GameState
- * @param renderer Renderer for drawing primitives
- * @param gui GUI system for widgets (optional)
- */
-void game_draw(const GameState* state, LowLevelRenderer* renderer, LowLevelGUI* gui) {
-    // Draw main window
-    LowLevelWindow *w1 = gui->draw_new_window(10, 10, V_WIDTH - 20, V_HEIGHT - 20, "Tic-Tac-Toe");
-    
-    renderer->set_font(&font_5x5_obj);
-    
-    // Draw current player or game result
-    if (state->game_over) {
-        if (state->winner == 1) {
-            renderer->draw_string(20, 40, "X WINS!", true);
-        } else if (state->winner == 2) {
-            renderer->draw_string(20, 40, "O WINS!", true);
-        } else {
-            renderer->draw_string(20, 40, "TIE GAME!", true);
-        }
-        renderer->draw_string(20, 55, "Touch or KEY0 to restart", true);
-    } else {
-        char turn_text[30];
-        snprintf(turn_text, sizeof(turn_text), "Turn: %s", state->current_player == 1 ? "X" : "O");
-        renderer->draw_string(20, 40, turn_text, true);
-        renderer->draw_string(20, 55, "Touch cell or use keys", true);
-    }
-    
-    // Draw game board (use same layout as touch detection!)
-    int board_x = V_WIDTH - BOARD_SIZE - 20;
-    
-    // Draw current turn indicator (large, on left side)
-    if (!state->game_over) {
-        int indicator_x = 60;
-        int indicator_y = V_HEIGHT / 2;
-        int piece_offset = CELL_SIZE / 4;
-        
-        if (state->current_player == 1) {
-            // Draw large X
-            renderer->draw_line(indicator_x - piece_offset, indicator_y - piece_offset,
-                              indicator_x + piece_offset, indicator_y + piece_offset, true, 4);
-            renderer->draw_line(indicator_x + piece_offset, indicator_y - piece_offset,
-                              indicator_x - piece_offset, indicator_y + piece_offset, true, 4);
-        } else {
-            // Draw large O
-            int piece_radius = CELL_SIZE / 4;
-            renderer->draw_circle(indicator_x, indicator_y, piece_radius, true);
-            renderer->draw_circle(indicator_x, indicator_y, piece_radius - 1, true);
-            renderer->draw_circle(indicator_x, indicator_y, piece_radius - 2, true);
-            renderer->draw_circle(indicator_x, indicator_y, piece_radius - 3, true);
-        }
-    }
-        // Draw grid lines
-    for (int i = 1; i < 3; i++) {
-        // Vertical lines
-        renderer->draw_line(board_x + i * CELL_SIZE, BOARD_Y, 
-                          board_x + i * CELL_SIZE, BOARD_Y + BOARD_SIZE, true, 2);
-        // Horizontal lines
-        renderer->draw_line(board_x, BOARD_Y + i * CELL_SIZE,
-                          board_x + BOARD_SIZE, BOARD_Y + i * CELL_SIZE, true, 2);
-    }
-    
-    // Draw outer border
-    renderer->draw_rectangle(board_x, BOARD_Y, BOARD_SIZE, BOARD_SIZE, true, 3);
-    
-    // Draw X's and O's
-    for (int row = 0; row < 3; row++) {
-        for (int col = 0; col < 3; col++) {
-            int cell_x = board_x + col * CELL_SIZE;
-            int cell_y = BOARD_Y + row * CELL_SIZE;
-            int center_x = cell_x + CELL_SIZE / 2;
-            int center_y = cell_y + CELL_SIZE / 2;
-            
-            // Highlight selected cell (for button navigation)
-            if (!state->game_over && row == state->selected_row && col == state->selected_col) {
-                renderer->draw_rectangle(cell_x + 5, cell_y + 5, CELL_SIZE - 10, CELL_SIZE - 10, true, 1);
-            }
-            
-            if (state->board[row][col] == 1) {
-                // Draw X
-                int offset = CELL_SIZE / 4;
-                renderer->draw_line(center_x - offset, center_y - offset,
-                                  center_x + offset, center_y + offset, true, 3);
-                renderer->draw_line(center_x + offset, center_y - offset,
-                                  center_x - offset, center_y + offset, true, 3);
-            } else if (state->board[row][col] == 2) {
-                // Draw O
-                int radius = CELL_SIZE / 4;
-                renderer->draw_circle(center_x, center_y, radius, true);
-                renderer->draw_circle(center_x, center_y, radius - 1, true);
-                renderer->draw_circle(center_x, center_y, radius - 2, true);
-            }
-        }
-    }
-    
-    // Draw statistics at bottom
-    char stats[60];
-    snprintf(stats, sizeof(stats), "X:%d  O:%d  Tie:%d  Moves:%d", 
-             state->x_wins, state->o_wins, state->ties, state->total_moves);
-    renderer->draw_string(20, V_HEIGHT - 40, stats, true);
-}
 
 // ============================================================================
 // MAIN PROGRAM
@@ -835,16 +315,17 @@ int main()
         .debug_verbose = false
     };
     
-    // Initialize game state
+    // Create InputManager for processing inputs
-    GameState game_state;
+    InputManager input_manager(touch, &config);
-    // Initialize statistics (persists across game restarts)
+    
-    game_state.x_wins = 0;
+    // Create game instance (polymorphic - can swap for other games later)
-    game_state.o_wins = 0;
+    Game* current_game = new TicTacToeGame(V_WIDTH, V_HEIGHT, &renderer, &gui);
-    game_state.ties = 0;
+    
-    game_init(&game_state);
+    // Initialize game
+    current_game->init();
     
     // Draw initial game graphics
-    game_draw(&game_state, &renderer, &gui);
+    current_game->draw();
     
     // Refresh the screen with the rendered GUI (async on Core 1)
     refresh_screen_async(bit_buffer, display);
@@ -935,16 +416,16 @@ int main()
         bool needs_refresh = false;
         
         // 1. Process button input first (higher priority)
-        input = process_button_input(config);
+        input = input_manager.process_button_input();
         if (input.valid) {
-            needs_refresh = game_update(&game_state, input, config, &renderer);
+            needs_refresh = current_game->update(input);
         }
         
         // 2. Process touch input (if no button was pressed)
         if (!input.valid) {
-            input = process_touch_input(config, &last_touch_time);
+            input = input_manager.process_touch_input(&last_touch_time);
             if (input.valid) {
-                needs_refresh = game_update(&game_state, input, config, &renderer);
+                needs_refresh = current_game->update(input);
             }
         }
         
@@ -952,7 +433,7 @@ int main()
         if (needs_refresh || pending_refresh) {
             // Clear buffer and redraw entire UI with updated state
             memset(bit_buffer, 0, V_WIDTH * V_HEIGHT / 8);
-            game_draw(&game_state, &renderer, &gui);
+            current_game->draw();
             
             // Request async refresh (non-blocking - handled by Core 1)
             bool refresh_started = refresh_screen_async(bit_buffer, display);

board_config.h

@@ -16,9 +16,9 @@
 // ============================================================================
 
 // ---- SELECT YOUR BOARD HERE ----
-#define BOARD_FEATHER_TFT      // Feather RP2350 + 4.0" TFT ST7796
+// #define BOARD_FEATHER_TFT      // Feather RP2350 + 4.0" TFT ST7796
 // #define BOARD_PICO2_TFT        // Pico 2 + 4.0" TFT ST7796
-//#define BOARD_PICO2_EINK       // Pico 2 + E-Ink Display
+#define BOARD_PICO2_EINK       // Pico 2 + E-Ink Display
 // --------------------------------
 
 // ============================================================================

games/tic_tac_toe.cpp

@@ -0,0 +1,304 @@
+// ============================================================================
+// TIC-TAC-TOE GAME IMPLEMENTATION
+// ============================================================================
+// Game logic, input handling, and rendering for Tic-Tac-Toe
+
+#include "tic_tac_toe.h"
+#include "board_config.h"
+#include <stdio.h>
+#include <string.h>
+
+// Font reference from display system
+extern Font font_5x5_obj;
+
+TicTacToeGame::TicTacToeGame(uint16_t width, uint16_t height, LowLevelRenderer* renderer, LowLevelGUI* gui)
+    : Game(width, height, renderer, gui) {
+    // Initialize statistics to zero
+    state.x_wins = 0;
+    state.o_wins = 0;
+    state.ties = 0;
+}
+
+void TicTacToeGame::init() {
+    // Clear the board
+    for (int row = 0; row < 3; row++) {
+        for (int col = 0; col < 3; col++) {
+            state.board[row][col] = 0;
+        }
+    }
+    
+    state.current_player = 1;  // X starts
+    state.winner = 0;
+    state.selected_row = 1;    // Start in center
+    state.selected_col = 1;
+    state.game_over = false;
+    state.total_moves = 0;
+    
+    // Keep win statistics across games
+    // state.x_wins, state.o_wins, state.ties remain unchanged
+}
+
+uint8_t TicTacToeGame::check_winner() {
+    // Check rows
+    for (int row = 0; row < 3; row++) {
+        if (state.board[row][0] != 0 && 
+            state.board[row][0] == state.board[row][1] && 
+            state.board[row][1] == state.board[row][2]) {
+            return state.board[row][0];
+        }
+    }
+    
+    // Check columns
+    for (int col = 0; col < 3; col++) {
+        if (state.board[0][col] != 0 && 
+            state.board[0][col] == state.board[1][col] && 
+            state.board[1][col] == state.board[2][col]) {
+            return state.board[0][col];
+        }
+    }
+    
+    // Check diagonals
+    if (state.board[0][0] != 0 && 
+        state.board[0][0] == state.board[1][1] && 
+        state.board[1][1] == state.board[2][2]) {
+        return state.board[0][0];
+    }
+    
+    if (state.board[0][2] != 0 && 
+        state.board[0][2] == state.board[1][1] && 
+        state.board[1][1] == state.board[2][0]) {
+        return state.board[0][2];
+    }
+    
+    // Check for tie (board full)
+    bool board_full = true;
+    for (int row = 0; row < 3; row++) {
+        for (int col = 0; col < 3; col++) {
+            if (state.board[row][col] == 0) {
+                board_full = false;
+                break;
+            }
+        }
+        if (!board_full) break;
+    }
+    
+    if (board_full) return 3; // Tie
+    return 0; // No winner yet
+}
+
+bool TicTacToeGame::update(const InputEvent& event) {
+    bool needs_refresh = false;
+    
+    switch (event.type) {
+        case INPUT_TOUCH_DOWN: {
+            // If game is over, restart on touch
+            if (state.game_over) {
+                init();
+                needs_refresh = true;
+                break;
+            }
+
+            printf("Touch down at (%d,%d)\n", event.x, event.y);
+            
+            // Calculate board position (must match draw()!)
+            int board_x = width - BOARD_SIZE - 20;
+            
+            // Check if touch is within board
+            if (event.x >= board_x && event.x < board_x + BOARD_SIZE &&
+                event.y >= BOARD_Y && event.y < BOARD_Y + BOARD_SIZE) {
+                
+                int touched_col = (event.x - board_x) / CELL_SIZE;
+                int touched_row = (event.y - BOARD_Y) / CELL_SIZE;
+                
+                // Clamp to valid range (safety check)
+                if (touched_row >= 0 && touched_row < 3 && touched_col >= 0 && touched_col < 3) {
+                    // Place piece if cell is empty
+                    if (state.board[touched_row][touched_col] == 0) {
+                        state.board[touched_row][touched_col] = state.current_player;
+                        state.total_moves++;
+                        
+                        // Check for winner
+                        state.winner = check_winner();
+                        if (state.winner != 0) {
+                            state.game_over = true;
+                            if (state.winner == 1) state.x_wins++;
+                            else if (state.winner == 2) state.o_wins++;
+                            else if (state.winner == 3) state.ties++;
+                        } else {
+                            // Switch player
+                            state.current_player = (state.current_player == 1) ? 2 : 1;
+                        }
+                        
+                        needs_refresh = true;
+                        
+                        printf("Touch at [%d,%d] (pixel %d,%d) by player %d\n", 
+                               touched_row, touched_col, event.x, event.y,
+                               state.current_player == 1 ? 2 : 1);
+                    } else {
+                        printf("Cell [%d,%d] already occupied\n", touched_row, touched_col);
+                    }
+                }
+            } else {
+                printf("Touch outside board: %d,%d\n", event.x, event.y);
+            }
+            break;
+        }
+            
+        case INPUT_BUTTON_0:
+            // KEY0: Move selection (for button-only boards)
+            if (!state.game_over) {
+                // Move to next cell, skipping occupied ones
+                int attempts = 0;
+                do {
+                    state.selected_col++;
+                    if (state.selected_col > 2) {
+                        state.selected_col = 0;
+                        state.selected_row++;
+                        if (state.selected_row > 2) {
+                            state.selected_row = 0;
+                        }
+                    }
+                    attempts++;
+                    // If we've tried all 9 cells, stop (game might be full)
+                    if (attempts >= 9) break;
+                } while (state.board[state.selected_row][state.selected_col] != 0);
+                
+                needs_refresh = true;
+                printf("Selection moved to [%d,%d]\n", state.selected_row, state.selected_col);
+            } else {
+                // Restart game
+                init();
+                needs_refresh = true;
+            }
+            break;
+            
+        case INPUT_BUTTON_1:
+            // KEY1: Place piece at selected position
+            if (!state.game_over) {
+                if (state.board[state.selected_row][state.selected_col] == 0) {
+                    state.board[state.selected_row][state.selected_col] = state.current_player;
+                    state.total_moves++;
+                    
+                    // Check for winner
+                    state.winner = check_winner();
+                    if (state.winner != 0) {
+                        state.game_over = true;
+                        if (state.winner == 1) state.x_wins++;
+                        else if (state.winner == 2) state.o_wins++;
+                        else if (state.winner == 3) state.ties++;
+                    } else {
+                        // Switch player
+                        state.current_player = (state.current_player == 1) ? 2 : 1;
+                    }
+                    
+                    needs_refresh = true;
+                    
+                    printf("Piece placed at [%d,%d]\n", state.selected_row, state.selected_col);
+                }
+            }
+            break;
+            
+        default:
+            break;
+    }
+    
+    return needs_refresh;
+}
+
+void TicTacToeGame::draw() {
+    // Draw main window
+    LowLevelWindow *w1 = gui->draw_new_window(10, 10, width - 20, height - 20, "Tic-Tac-Toe");
+    
+    renderer->set_font(&font_5x5_obj);
+    
+    // Draw current player or game result
+    if (state.game_over) {
+        if (state.winner == 1) {
+            renderer->draw_string(20, 40, "X WINS!", true);
+        } else if (state.winner == 2) {
+            renderer->draw_string(20, 40, "O WINS!", true);
+        } else {
+            renderer->draw_string(20, 40, "TIE GAME!", true);
+        }
+        renderer->draw_string(20, 55, "Touch or KEY0 to restart", true);
+    } else {
+        char turn_text[30];
+        snprintf(turn_text, sizeof(turn_text), "Turn: %s", state.current_player == 1 ? "X" : "O");
+        renderer->draw_string(20, 40, turn_text, true);
+        renderer->draw_string(20, 55, "Touch cell or use keys", true);
+    }
+    
+    // Draw game board (use same layout as touch detection!)
+    int board_x = width - BOARD_SIZE - 20;
+    
+    // Draw current turn indicator (large, on left side)
+    if (!state.game_over) {
+        int indicator_x = 60;
+        int indicator_y = height / 2;
+        int piece_offset = CELL_SIZE / 4;
+        
+        if (state.current_player == 1) {
+            // Draw large X
+            renderer->draw_line(indicator_x - piece_offset, indicator_y - piece_offset,
+                              indicator_x + piece_offset, indicator_y + piece_offset, true, 4);
+            renderer->draw_line(indicator_x + piece_offset, indicator_y - piece_offset,
+                              indicator_x - piece_offset, indicator_y + piece_offset, true, 4);
+        } else {
+            // Draw large O
+            int piece_radius = CELL_SIZE / 4;
+            renderer->draw_circle(indicator_x, indicator_y, piece_radius, true);
+            renderer->draw_circle(indicator_x, indicator_y, piece_radius - 1, true);
+            renderer->draw_circle(indicator_x, indicator_y, piece_radius - 2, true);
+            renderer->draw_circle(indicator_x, indicator_y, piece_radius - 3, true);
+        }
+    }
+    
+    // Draw grid lines
+    for (int i = 1; i < 3; i++) {
+        // Vertical lines
+        renderer->draw_line(board_x + i * CELL_SIZE, BOARD_Y, 
+                          board_x + i * CELL_SIZE, BOARD_Y + BOARD_SIZE, true, 2);
+        // Horizontal lines
+        renderer->draw_line(board_x, BOARD_Y + i * CELL_SIZE,
+                          board_x + BOARD_SIZE, BOARD_Y + i * CELL_SIZE, true, 2);
+    }
+    
+    // Draw outer border
+    renderer->draw_rectangle(board_x, BOARD_Y, BOARD_SIZE, BOARD_SIZE, true, 3);
+    
+    // Draw X's and O's
+    for (int row = 0; row < 3; row++) {
+        for (int col = 0; col < 3; col++) {
+            int cell_x = board_x + col * CELL_SIZE;
+            int cell_y = BOARD_Y + row * CELL_SIZE;
+            int center_x = cell_x + CELL_SIZE / 2;
+            int center_y = cell_y + CELL_SIZE / 2;
+            
+            // Highlight selected cell (for button navigation)
+            if (!state.game_over && row == state.selected_row && col == state.selected_col) {
+                renderer->draw_rectangle(cell_x + 5, cell_y + 5, CELL_SIZE - 10, CELL_SIZE - 10, true, 1);
+            }
+            
+            if (state.board[row][col] == 1) {
+                // Draw X
+                int offset = CELL_SIZE / 4;
+                renderer->draw_line(center_x - offset, center_y - offset,
+                                  center_x + offset, center_y + offset, true, 3);
+                renderer->draw_line(center_x + offset, center_y - offset,
+                                  center_x - offset, center_y + offset, true, 3);
+            } else if (state.board[row][col] == 2) {
+                // Draw O
+                int radius = CELL_SIZE / 4;
+                renderer->draw_circle(center_x, center_y, radius, true);
+                renderer->draw_circle(center_x, center_y, radius - 1, true);
+                renderer->draw_circle(center_x, center_y, radius - 2, true);
+            }
+        }
+    }
+    
+    // Draw statistics at bottom
+    char stats[60];
+    snprintf(stats, sizeof(stats), "X:%d  O:%d  Tie:%d  Moves:%d", 
+             state.x_wins, state.o_wins, state.ties, state.total_moves);
+    renderer->draw_string(20, height - 40, stats, true);
+}

games/tic_tac_toe.h

@@ -0,0 +1,78 @@
+// ============================================================================
+// TIC-TAC-TOE GAME HEADER
+// ============================================================================
+// Concrete implementation of the Game interface for Tic-Tac-Toe
+
+#ifndef TIC_TAC_TOE_H
+#define TIC_TAC_TOE_H
+
+#include "game.h"
+
+/**
+ * @brief Tic-Tac-Toe game implementation
+ * 
+ * Classic two-player Tic-Tac-Toe game with:
+ * - Touch input: Tap cells to place pieces
+ * - Button input: KEY0 moves selection, KEY1 places piece
+ * - Win detection: Rows, columns, and diagonals
+ * - Statistics tracking: Wins, ties, total moves
+ * - Visual feedback: Selection highlight, turn indicator
+ */
+class TicTacToeGame : public Game {
+public:
+    /**
+     * @brief Construct a new Tic-Tac-Toe game
+     * @param width Display width in pixels
+     * @param height Display height in pixels
+     * @param renderer Pointer to low-level rendering interface
+     * @param gui Pointer to GUI drawing primitives
+     */
+    TicTacToeGame(uint16_t width, uint16_t height, LowLevelRenderer* renderer, LowLevelGUI* gui);
+    
+    /**
+     * @brief Initialize game state (reset board, keep statistics)
+     */
+    void init() override;
+    
+    /**
+     * @brief Update game state based on input event
+     * @param event Input event from InputManager
+     * @return true if screen redraw is needed
+     */
+    bool update(const InputEvent& event) override;
+    
+    /**
+     * @brief Draw the game to the display buffer
+     */
+    void draw() override;
+
+private:
+    // Game state
+    struct GameState {
+        uint8_t board[3][3];     // 0=empty, 1=X, 2=O
+        uint8_t current_player;  // 1=X, 2=O
+        uint8_t winner;          // 0=none, 1=X wins, 2=O wins, 3=tie
+        uint8_t selected_row;    // Currently selected cell (for button navigation)
+        uint8_t selected_col;
+        bool game_over;
+        
+        // Game statistics
+        uint32_t x_wins;
+        uint32_t o_wins;
+        uint32_t ties;
+        uint32_t total_moves;
+    } state;
+    
+    /**
+     * @brief Check if there's a winner on the board
+     * @return 0=no winner, 1=X wins, 2=O wins, 3=tie
+     */
+    uint8_t check_winner();
+    
+    // Board layout constants
+    static const int BOARD_SIZE = 200;
+    static const int CELL_SIZE = BOARD_SIZE / 3;
+    static const int BOARD_Y = 80;  // Y position below title
+};
+
+#endif // TIC_TAC_TOE_H

lib/game.h

@@ -0,0 +1,82 @@
+// ============================================================================
+// ABSTRACT GAME BASE CLASS
+// ============================================================================
+// Defines the interface all games must implement
+// Provides polymorphic game architecture for modular design
+
+#ifndef GAME_H
+#define GAME_H
+
+#include <stdint.h>
+#include "input_event.h"
+#include "display/low_level_render.h"
+#include "display/low_level_gui.h"
+
+/**
+ * @brief Abstract base class for all games
+ * 
+ * Games inherit from this class and implement the three core methods:
+ * - init(): Set up initial game state
+ * - update(): Process input events and update game logic
+ * - draw(): Render the game to the display buffer
+ * 
+ * The main loop in basic1.cpp calls these methods polymorphically,
+ * allowing different games to run with the same infrastructure.
+ */
+class Game {
+public:
+    /**
+     * @brief Construct a new Game
+     * @param width Display width in pixels
+     * @param height Display height in pixels
+     * @param renderer Pointer to low-level rendering interface
+     * @param gui Pointer to GUI drawing primitives
+     */
+    Game(uint16_t width, uint16_t height, LowLevelRenderer* renderer, LowLevelGUI* gui)
+        : width(width), height(height), renderer(renderer), gui(gui) {
+    }
+    
+    /**
+     * @brief Virtual destructor for proper cleanup of derived classes
+     */
+    virtual ~Game() {}
+    
+    /**
+     * @brief Initialize game state
+     * 
+     * Called once when the game starts. Set up initial values,
+     * reset statistics, prepare the game board, etc.
+     */
+    virtual void init() = 0;
+    
+    /**
+     * @brief Update game state based on input event
+     * 
+     * Process the input event and update game logic accordingly.
+     * This is where game rules, win conditions, state transitions happen.
+     * 
+     * @param event Input event from InputManager
+     * @return true if screen redraw is needed, false otherwise
+     */
+    virtual bool update(const InputEvent& event) = 0;
+    
+    /**
+     * @brief Draw the game to the display buffer
+     * 
+     * Render all game graphics using the renderer and gui objects.
+     * This is called after update() returns true.
+     * The actual screen refresh happens in the main loop on Core 1.
+     */
+    virtual void draw() = 0;
+
+protected:
+    // Display dimensions
+    uint16_t width;
+    uint16_t height;
+    
+    // Rendering interfaces (provided by basic1.cpp)
+    LowLevelRenderer* renderer;
+    LowLevelGUI* gui;
+};
+
+#endif // GAME_H

lib/input_event.h

@@ -0,0 +1,34 @@
+// ============================================================================
+// INPUT EVENT HEADER
+// ============================================================================
+// Shared input event structures used by InputManager and Game classes
+// Extracted from basic1.cpp for modular game architecture
+
+#ifndef INPUT_EVENT_H
+#define INPUT_EVENT_H
+
+#include <stdint.h>
+
+// Input event types
+enum InputType {
+    INPUT_NONE = 0,
+    INPUT_TOUCH_DOWN,
+    INPUT_TOUCH_MOVE,
+    INPUT_TOUCH_UP,
+    INPUT_BUTTON_0,
+    INPUT_BUTTON_1,
+    INPUT_GESTURE
+};
+
+// Unified input event structure
+struct InputEvent {
+    InputType type;
+    int16_t x;
+    int16_t y;
+    uint8_t gesture_code;  // For gesture events
+    uint8_t button_id;     // For button events
+    uint8_t pressure;      // Touch pressure/weight
+    bool valid;            // Set to true if event is valid
+};
+
+#endif // INPUT_EVENT_H

lib/input_manager.cpp

@@ -0,0 +1,154 @@
+// ============================================================================
+// INPUT MANAGER IMPLEMENTATION
+// ============================================================================
+// Processes touch and button inputs into InputEvent objects
+
+#include "input_manager.h"
+#include "pico/stdlib.h"
+#include "board_config.h"
+#include <stdio.h>
+
+// External interrupt flags from basic1.cpp
+extern volatile bool touch_interrupt_flag;
+extern volatile bool touch_event_down;
+extern volatile bool button_key0_pressed;
+extern volatile bool button_key1_pressed;
+
+// GameConfig struct definition (matches basic1.cpp)
+struct GameConfig {
+    uint32_t touch_debounce_ms;
+    uint32_t button_debounce_ms;
+    bool enable_gestures;
+    bool enable_continuous_draw;
+    bool debug_verbose;
+};
+
+InputManager::InputManager(LowLevelTouch* touch, const GameConfig* config)
+    : touch(touch), config(config) {
+}
+
+InputEvent InputManager::process_touch_input(uint32_t* last_time) {
+    InputEvent event = {INPUT_NONE, 0, 0, 0, 0, 0, false};
+    
+    // Check if touch interrupt flag is set
+    if (!touch_interrupt_flag) {
+        return event;  // No touch event
+    }
+    
+    printf("Processing touch: flag=%d, event_down=%d\n", touch_interrupt_flag, touch_event_down);
+    
+    // Don't clear the flag yet - we may still be processing continuous touch
+    
+    // Check if touch is active
+    if (!touch_event_down) {
+        // Touch released - reset timing for next touch
+        touch_interrupt_flag = false;
+        *last_time = 0;  // Reset so next touch is treated as new touch-down
+        event.type = INPUT_TOUCH_UP;
+        event.valid = true;
+        printf("Touch UP\n");
+        return event;
+    }
+    
+    // Touch is down - check debounce timing
+    uint32_t now = to_ms_since_boot(get_absolute_time());
+    if (now - *last_time < config->touch_debounce_ms) {
+        return event;  // Too soon, skip
+    }
+    
+    // Read touch data
+    TouchData touch_data;
+    if (!touch || !touch->read_touch(&touch_data)) {
+        // Clear flag even if read failed to prevent getting stuck
+        touch_interrupt_flag = false;
+        printf("Touch read FAILED\n");
+        return event;  // Read failed
+    }
+    
+    // Clear the interrupt flag after successfully reading touch data
+    // This allows the next touch interrupt to be detected
+    touch_interrupt_flag = false;
+    
+    printf("Touch DOWN at (%d,%d)\n", touch_data.points[0].x, touch_data.points[0].y);
+    
+    // Populate event structure
+    event.x = touch_data.points[0].x;
+    event.y = touch_data.points[0].y;
+    event.pressure = touch_data.points[0].pressure;
+    event.gesture_code = touch_data.gesture;
+    event.valid = true;
+    
+    // Determine event type
+    if (*last_time == 0) {
+        event.type = INPUT_TOUCH_DOWN;
+    } else {
+        event.type = INPUT_TOUCH_MOVE;
+    }
+    
+    // Handle gesture events
+    if (config->enable_gestures && touch_data.gesture != 0) {
+        event.type = INPUT_GESTURE;
+        if (config->debug_verbose) {
+            printf("Gesture: 0x%02X (%s)\n", event.gesture_code, get_gesture_name(event.gesture_code));
+        }
+    }
+    
+    *last_time = now;
+    return event;
+}
+
+InputEvent InputManager::process_button_input() {
+    InputEvent event = {INPUT_NONE, 0, 0, 0, 0, 0, false};
+    
+#ifdef BUTTON_KEY0_PIN
+    // Check KEY0
+    if (button_key0_pressed) {
+        button_key0_pressed = false;
+        sleep_ms(config->button_debounce_ms);
+        
+        if (gpio_get(BUTTON_KEY0_PIN) == 0) {  // Verify still pressed
+            event.type = INPUT_BUTTON_0;
+            event.button_id = 0;
+            event.valid = true;
+            
+            if (config->debug_verbose) {
+                printf("Button KEY0 action triggered\n");
+            }
+            return event;
+        }
+    }
+    
+#ifdef BUTTON_KEY1_PIN
+    // Check KEY1
+    if (button_key1_pressed) {
+        button_key1_pressed = false;
+        sleep_ms(config->button_debounce_ms);
+        
+        if (gpio_get(BUTTON_KEY1_PIN) == 0) {  // Verify still pressed
+            event.type = INPUT_BUTTON_1;
+            event.button_id = 1;
+            event.valid = true;
+            
+            if (config->debug_verbose) {
+                printf("Button KEY1 action triggered\n");
+            }
+            return event;
+        }
+    }
+#endif
+#endif
+    
+    return event;
+}
+
+const char* InputManager::get_gesture_name(uint8_t gesture_code) {
+    switch(gesture_code) {
+        case 0x10: return "Move Up";
+        case 0x14: return "Move Right";
+        case 0x18: return "Move Down";
+        case 0x1C: return "Move Left";
+        case 0x48: return "Zoom In";
+        case 0x49: return "Zoom Out";
+        default: return "Unknown";
+    }
+}

lib/input_manager.h

@@ -0,0 +1,64 @@
+// ============================================================================
+// INPUT MANAGER HEADER
+// ============================================================================
+// Handles all input processing and debouncing for touch and button inputs
+// Converts hardware events into InputEvent objects for games to consume
+
+#ifndef INPUT_MANAGER_H
+#define INPUT_MANAGER_H
+
+#include <stdint.h>
+#include "input_event.h"
+#include "display/low_level_touch.h"
+
+// Forward declaration - avoid pulling in full basic1.cpp
+struct GameConfig;
+
+/**
+ * @brief Input Manager - Processes touch and button inputs
+ * 
+ * Responsibilities:
+ * - Reading touch controller data
+ * - Debouncing touch and button events
+ * - Converting raw inputs to InputEvent objects
+ * - Gesture recognition
+ * 
+ * Does NOT handle:
+ * - Button GPIO initialization (stays in basic1.cpp)
+ * - Interrupt handler registration (stays in basic1.cpp)
+ */
+class InputManager {
+public:
+    /**
+     * @brief Construct InputManager with hardware references
+     * @param touch Pointer to touch controller interface
+     * @param config Pointer to game configuration
+     */
+    InputManager(LowLevelTouch* touch, const GameConfig* config);
+    
+    /**
+     * @brief Process touch input from controller
+     * @param last_time Pointer to last touch timestamp for debouncing
+     * @return InputEvent (valid=false if no valid input)
+     */
+    InputEvent process_touch_input(uint32_t* last_time);
+    
+    /**
+     * @brief Process button input from GPIO flags
+     * @return InputEvent (valid=false if no valid input)
+     */
+    InputEvent process_button_input();
+    
+    /**
+     * @brief Get human-readable gesture name
+     * @param gesture_code Gesture code from touch controller
+     * @return Constant string with gesture name
+     */
+    static const char* get_gesture_name(uint8_t gesture_code);
+
+private:
+    LowLevelTouch* touch;
+    const GameConfig* config;
+};
+
+#endif // INPUT_MANAGER_H