Added TransitionControl and plot rewinding.

New component overlays main view and handles middle clicks/drags
to performing rewinding. Also sports smooth transitioning back to
current projection whenever the mouse button is lifted.

Next up, the same kind of transitions in the displayed values.

1 files changed, 23 insertions, 0 deletions

diff --git a/rewindworkerthread.cpp b/rewindworkerthread.cpp
new file mode 100644
index 0000000..f9fa999
--- /dev/null
+++ b/rewindworkerthread.cpp
@@ -0,0 +1,23 @@
+#include "rewindworkerthread.h"
+
+// The full duration (usecs) of the restoration animation
+static const double DURATION = 250000;
+
+// The time to wait (usecs) before the next animation tick
+static const double TICK_TIME = DURATION / 60.0;
+
+// The amount to increase 't' per time step
+static const double TICK_SIZE = TICK_TIME / DURATION;
+
+void RewindWorkerThread::run()
+{
+    double t = m_control->t();
+
+    while (t + TICK_SIZE < 1.0) {
+        t += TICK_SIZE;
+        m_control->setT(t);
+        QThread::usleep(TICK_TIME);
+    }
+
+    m_control->setT(1.0);
+}