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diff --git a/util/fbcompose/TickTracker.cc b/util/fbcompose/TickTracker.cc
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+/** TickTracker.cc file for the fluxbox compositor. */
+
+// Copyright (c) 2011 Gediminas Liktaras (gliktaras at gmail dot com)
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+
+#include "TickTracker.hh"
+
+#include "Logging.hh"
+
+using namespace FbCompositor;
+
+
+//--- CONSTANTS ----------------------------------------------------------------
+
+// The accuracy of the timer (1.0 = 1 second).
+const double EPSILON = 1e-6;
+
+
+//--- CONSTRUCTORS AND DESTRUCTORS ---------------------------------------------
+
+// Constructor.
+TickTracker::TickTracker() {
+    m_is_running = false;
+    m_tick_size = 1000000;
+    m_ticks_per_second = 1.0;
+}
+
+// Copy constructor.
+TickTracker::TickTracker(const TickTracker &other) :
+    m_is_running(other.m_is_running),
+    m_startTime(other.m_startTime),
+    m_tick_size(other.m_tick_size),
+    m_ticks_per_second(other.m_ticks_per_second),
+    m_observed_ticks(other.m_observed_ticks) {
+}
+
+// Assignment operator.
+TickTracker &TickTracker::operator=(const TickTracker &other) {
+    if (this != &other) {
+        m_is_running = other.m_is_running;
+        m_startTime = other.m_startTime;
+        m_tick_size = other.m_tick_size;
+        m_ticks_per_second = other.m_ticks_per_second;
+        m_observed_ticks = other.m_observed_ticks;
+    }
+    return *this;
+}
+
+// Destructor.
+TickTracker::~TickTracker() { }
+
+
+//--- TIMER MANIPULATION -------------------------------------------------------
+
+// Starts the timer.
+void TickTracker::start() {
+    if (gettimeofday(&m_startTime, NULL)) {
+        throw TimeException("Cannot obtain the current time.");
+    }
+    m_observed_ticks = 0;
+    m_is_running = true;
+}
+
+/** Stops the timer. */
+void TickTracker::stop() {
+    m_is_running = false;
+}
+
+
+//--- TIMER QUERIES ------------------------------------------------------------
+
+// Returns the new number of elapsed ticks since last call of this function.
+int TickTracker::newElapsedTicks() {
+    int total_ticks = totalElapsedTicks();
+    int new_ticks = total_ticks - m_observed_ticks;
+    m_observed_ticks = total_ticks;
+
+    if (new_ticks < 0) {
+        return 0;
+    } else {
+        return new_ticks;
+    }
+}
+
+// Returns the total number of elapsed ticks.
+int TickTracker::totalElapsedTicks() {
+    static timeval now;
+
+    if (gettimeofday(&now, NULL)) {
+        throw TimeException("Cannot obtain the current time.");
+    }
+
+    return tickDifference(now, m_startTime);
+}
+
+
+// Sets the size of a tick.
+void TickTracker::setTickSize(int usec) {
+    if (usec < 1) {
+        throw TimeException("Invalid tick size.");
+    }
+
+    m_tick_size = usec;
+    m_ticks_per_second = 1000000.0 / usec;
+}
+
+
+//--- INTERNAL FUNTIONS --------------------------------------------------------
+
+// Returns the difference in time between two timevals.
+// Function adapted from http://www.gnu.org/s/libc/manual/html_node/Elapsed-Time.html.
+timeval TickTracker::timeDifference(timeval t1, timeval t2) {
+    int n_sec;
+
+    if (t1.tv_usec < t2.tv_usec) {
+        n_sec = (t2.tv_usec - t1.tv_usec) / 1000000 + 1;
+        t2.tv_usec -= 1000000 * n_sec;
+        t2.tv_sec += n_sec;
+    }
+    if (t1.tv_usec - t2.tv_usec > 1000000) {
+        n_sec = (t1.tv_usec - t2.tv_usec) / 1000000;
+        t2.tv_usec += 1000000 * n_sec;
+        t2.tv_sec -= n_sec;
+    }
+
+    timeval diff;
+    diff.tv_sec = t1.tv_sec - t2.tv_sec;
+    diff.tv_usec = t1.tv_usec - t2.tv_usec;
+    return diff;
+}
+
+// Returns the difference between two timevals in ticks.
+int TickTracker::tickDifference(const timeval &t1, const timeval &t2) {
+    timeval diff = timeDifference(t1, t2);
+
+    double raw_diff = diff.tv_sec * m_ticks_per_second + (double(diff.tv_usec) / m_tick_size);
+    return int(raw_diff + EPSILON);
+}