src/DrawThread.hpp

   1 /*
   2 Copyright_License {
   3
   4   XCSoar Glide Computer - http://www.xcsoar.org/
   5   Copyright (C) 2000-2013 The XCSoar Project
   6   A detailed list of copyright holders can be found in the file "AUTHORS".
   7
   8   This program is free software; you can redistribute it and/or
   9   modify it under the terms of the GNU General Public License
  10   as published by the Free Software Foundation; either version 2
  11   of the License, or (at your option) any later version.
  12
  13   This program is distributed in the hope that it will be useful,
  14   but WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16   GNU General Public License for more details.
  17
  18   You should have received a copy of the GNU General Public License
  19   along with this program; if not, write to the Free Software
  20   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  21 }
  22 */
  23
  24 #ifndef XCSOAR_DRAW_THREAD_HPP
  25 #define XCSOAR_DRAW_THREAD_HPP
  26
  27 #include "Thread/RecursivelySuspensibleThread.hpp"
  28 #include "Thread/Trigger.hpp"
  29
  30 class GlueMapWindow;
  31
  32 /**
  33  * The DrawThread handles the rendering and drawing on the screen.
  34  * The Map and GaugeFLARM both are triggered on GPS updates synchronously,
  35  * which is why they are both handled by this thread.  The GaugeVario is
  36  * triggered on vario data which may be faster than GPS updates, which is
  37  * why it is not handled by this thread.
  38  *
  39  */
  40 class DrawThread : public RecursivelySuspensibleThread {
  41   enum {
  42     MIN_WAIT_TIME = 100,
  43   };
  44
  45   /**
  46    * This triggers a redraw.
  47    */
  48   Trigger trigger;
  49
  50   /** Pointer to the MapWindow */
  51   GlueMapWindow &map;
  52
  53 public:
  54   DrawThread(GlueMapWindow &_map)
  55     :map(_map) {}
  56
  57   /** Locks the Mutex and "pauses" the drawing thread */
  58   void BeginSuspend() {
  59     RecursivelySuspensibleThread::BeginSuspend();
  60     TriggerRedraw();
  61   }
  62
  63   void Suspend() {
  64     BeginSuspend();
  65     WaitUntilSuspended();
  66   }
  67
  68   /**
  69    * To be removed, only used by GlueMapWindow::Idle().
  70    */
  71   bool IsTriggered() {
  72     return trigger.Test();
  73   }
  74
  75   /**
  76    * Triggers a redraw.
  77    */
  78   void TriggerRedraw() {
  79     trigger.Signal();
  80   }
  81
  82   /**
  83    * Triggers thread shutdown.  Call join() after this to wait
  84    * synchronously for the thread to exit.
  85    */
  86   void BeginStop() {
  87     RecursivelySuspensibleThread::BeginStop();
  88     TriggerRedraw();
  89   }
  90
  91 protected:
  92   virtual void Run();
  93 };
  94
  95 #endif