1 files changed, 122 insertions, 0 deletions
diff --git a/src/utils/timer.cpp b/src/utils/timer.cpp
new file mode 100644
index 000000000..f6aab825c
--- /dev/null
+++ b/src/utils/timer.cpp
@@ -0,0 +1,122 @@
+/*
+ *  The ManaPlus Client
+ *  Copyright (C) 2011-2013  The ManaPlus Developers
+ *
+ *  This file is part of The ManaPlus Client.
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "utils/timer.h"
+
+#include "SDL_timer.h"
+
+#include <climits>
+
+#include "debug.h"
+
+namespace
+{
+#ifdef USE_SDL2
+    SDL_TimerID mLogicCounterId(0);
+    SDL_TimerID mSecondsCounterId(0);
+#else
+    SDL_TimerID mLogicCounterId(nullptr);
+    SDL_TimerID mSecondsCounterId(nullptr);
+#endif
+}  // namespace
+
+/**
+ * Tells the max tick value,
+ * setting it back to zero (and start again).
+ */
+static const int MAX_TICK_VALUE = INT_MAX / 2;
+
+volatile int tick_time;       /**< Tick counter */
+volatile int fps = 0;         /**< Frames counted in the last second */
+volatile int lps = 0;         /**< Logic processed per second */
+volatile int frame_count = 0; /**< Counts the frames during one second */
+volatile int logic_count = 0; /**< Counts the logic during one second */
+volatile int cur_time;
+
+static uint32_t nextTick(uint32_t interval, void *param A_UNUSED);
+static uint32_t nextSecond(uint32_t interval, void *param A_UNUSED);
+
+/**
+ * Advances game logic counter.
+ * Called every 10 milliseconds by SDL_AddTimer()
+ * @see MILLISECONDS_IN_A_TICK value
+ */
+static uint32_t nextTick(uint32_t interval, void *param A_UNUSED)
+{
+    tick_time++;
+    if (tick_time == MAX_TICK_VALUE)
+        tick_time = 0;
+    return interval;
+}
+
+/**
+ * Updates fps.
+ * Called every seconds by SDL_AddTimer()
+ */
+static uint32_t nextSecond(uint32_t interval, void *param A_UNUSED)
+{
+    fps = frame_count;
+    lps = logic_count;
+    frame_count = 0;
+    logic_count = 0;
+
+    return interval;
+}
+
+/**
+ * @return the elapsed time in milliseconds
+ * between two tick values.
+ */
+int get_elapsed_time(const int startTime)
+{
+    const int time = tick_time;
+    if (startTime <= time)
+    {
+        return (time - startTime) * MILLISECONDS_IN_A_TICK;
+    }
+    else
+    {
+        return (time + (MAX_TICK_VALUE - startTime))
+            * MILLISECONDS_IN_A_TICK;
+    }
+}
+
+int get_elapsed_time1(const int startTime)
+{
+    const int time = tick_time;
+    if (startTime <= time)
+        return time - startTime;
+    else
+        return time + (MAX_TICK_VALUE - startTime);
+}
+
+void startTimers()
+{
+    // Initialize logic and seconds counters
+    tick_time = 0;
+    mLogicCounterId = SDL_AddTimer(MILLISECONDS_IN_A_TICK, nextTick, nullptr);
+    mSecondsCounterId = SDL_AddTimer(1000, nextSecond, nullptr);
+}
+
+void stopTimers()
+{
+    SDL_RemoveTimer(mLogicCounterId);
+    SDL_RemoveTimer(mSecondsCounterId);
+}