refactor tetris's fall down logic

john0312 · Aug 18, 2024 · c750107 · c750107
1 parent ffcec1e
commit c750107
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Showing 6 changed files with 35 additions and 50 deletions.
diff --git a/fw/Core/Hitcon/App/Makefile b/fw/Core/Hitcon/App/Makefile
@@ -1,7 +1,7 @@
 .PHONY: format
 
 /tmp/test-tetris: *.cc *.h
-	g++ -g -O0 -DHITCON_TEST_MODE -o /tmp/test-tetris -I.. test-tetris.cc TetrisGame.cc
+	g++ -Wall -Wextra -pedantic -g -O0 -DHITCON_TEST_MODE -o /tmp/test-tetris -I.. test-tetris.cc TetrisGame.cc
 
 format:
 	clang-format -i *.cc *.h

diff --git a/fw/Core/Hitcon/App/TetrisApp.cc b/fw/Core/Hitcon/App/TetrisApp.cc
@@ -192,25 +192,9 @@ void TetrisApp::periodic_task_callback(void *) {
     }
 
     case hitcon::tetris::GAME_STATE_PLAYING: {
-      // check if it's time to fall down
-      unsigned now = SysTimer::GetTime();
-      unsigned fall_period;
-      if (hitcon::tetris::FALL_PERIOD >
-          game.game_get_cleared_lines() *
-              hitcon::tetris::SPEED_UP_PER_CLEAR_LINE) {
-        fall_period = hitcon::tetris::FALL_PERIOD -
-                      game.game_get_cleared_lines() *
-                          hitcon::tetris::SPEED_UP_PER_CLEAR_LINE;
-      } else {
-        fall_period = hitcon::tetris::MIN_FALL_PERIOD;
-      }
-
-      if (fall_period < hitcon::tetris::MIN_FALL_PERIOD) {
-        fall_period = hitcon::tetris::MIN_FALL_PERIOD;
-      }
-
-      if (now - last_fall_time >= fall_period) {
-        game.game_fall_down_tetromino();
+      static int last_fall_time = 0;
+      int now = static_cast<int>(SysTimer::GetTime());
+      if (game.game_fall_down_if_its_time(now, last_fall_time)) {
         last_fall_time = now;
       }
 

diff --git a/fw/Core/Hitcon/App/TetrisApp.h b/fw/Core/Hitcon/App/TetrisApp.h
@@ -48,7 +48,6 @@ class TetrisApp : public App {
   hitcon::tetris::TetrisGame game;
   hitcon::service::sched::PeriodicTask periodic_task;
 
-  unsigned last_fall_time = 0;
   void RecvAttackPacket(hitcon::service::xboard::PacketCallbackArg *packet);
 
  public:

diff --git a/fw/Core/Hitcon/App/TetrisGame.cc b/fw/Core/Hitcon/App/TetrisGame.cc
@@ -123,12 +123,6 @@ bool TetrisGame::generate_new_tetromino() {
   return place_tetromino(current_x, current_y);
 }
 
-void TetrisGame::game_fall_down_tetromino() {
-  if (state == GAME_STATE_PLAYING) {
-    fall_down_tetromino();
-  }
-}
-
 void TetrisGame::game_on_input(TetrisDirection direction) {
   if (state == GAME_STATE_PLAYING) {
     switch (direction) {
@@ -205,5 +199,23 @@ void TetrisGame::game_register_attack_enemy_callback(
   attack_enemy_callback = callback;
 }
 
+inline int max(int a, int b) { return a > b ? a : b; }
+
+/**
+ * Check if it's time to fall down the tetromino.
+ * If fall down, return true.
+ */
+bool TetrisGame::game_fall_down_if_its_time(int now, int last_fall_time) {
+  int fall_period =
+      max(MIN_FALL_PERIOD,
+          FALL_PERIOD - game_get_cleared_lines() * SPEED_UP_PER_CLEAR_LINE);
+
+  if (now - last_fall_time >= fall_period) {
+    fall_down_tetromino();
+    return true;
+  }
+  return false;
+}
+
 }  // namespace tetris
 }  // namespace hitcon
diff --git a/fw/Core/Hitcon/App/TetrisGame.h b/fw/Core/Hitcon/App/TetrisGame.h
@@ -6,11 +6,11 @@
 namespace hitcon {
 namespace tetris {
 
-constexpr unsigned FALL_PERIOD = 1000;            // ms
-constexpr unsigned UPDATE_INTERVAL = 200;         // ms
-constexpr unsigned SPEED_UP_PER_CLEAR_LINE = 50;  // ms
-constexpr unsigned MIN_FALL_PERIOD = 100;         // ms
-constexpr unsigned UPDATE_PRIORITY = 960;
+constexpr int FALL_PERIOD = 1000;            // ms
+constexpr int UPDATE_INTERVAL = 200;         // ms
+constexpr int SPEED_UP_PER_CLEAR_LINE = 50;  // ms
+constexpr int MIN_FALL_PERIOD = 100;         // ms
+constexpr int UPDATE_PRIORITY = 960;
 
 constexpr int BOARD_WIDTH = 8;
 constexpr int BOARD_HEIGHT = 16;
@@ -138,7 +138,7 @@ class TetrisGame {
   TetrisGame() = default;
   TetrisGame(unsigned (*rand)(void));
 
-  void game_fall_down_tetromino();
+  bool game_fall_down_if_its_time(int now, int last_fall_time);
   void game_on_input(TetrisDirection direction);
   void game_draw_to_display(display_buf_t *buf);
   inline void game_start_playing() { state = GAME_STATE_PLAYING; }

diff --git a/fw/Core/Hitcon/App/test-tetris.cc b/fw/Core/Hitcon/App/test-tetris.cc
@@ -56,26 +56,16 @@ void gameFunction() {
                std::chrono::system_clock::now().time_since_epoch())
         .count();
   };
-  auto prev_update = now_ms() - hitcon::tetris::FALL_PERIOD;
+  int prev_update = 0;
   game.game_start_playing();
   while (1) {
-    auto now = now_ms();
-
-    unsigned fall_period;
-    if (hitcon::tetris::FALL_PERIOD >
-        game.game_get_cleared_lines() *
-            hitcon::tetris::SPEED_UP_PER_CLEAR_LINE) {
-      fall_period = hitcon::tetris::FALL_PERIOD -
-                    game.game_get_cleared_lines() *
-                        hitcon::tetris::SPEED_UP_PER_CLEAR_LINE;
-    } else {
-      fall_period = hitcon::tetris::MIN_FALL_PERIOD;
-    }
-
-    if (now - prev_update >= fall_period) {
+    {
       std::lock_guard<std::mutex> lock(game_mutex);
-      game.game_fall_down_tetromino();
-      prev_update = now;
+      int now = now_ms();
+      if (game.game_fall_down_if_its_time(now, prev_update)) {
+        prev_update = now;
+      }
+
       if (game.game_get_state() == hitcon::tetris::GAME_STATE_GAME_OVER) {
         exit(0);
         break;