src/Renderer/OZRenderer.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_RENDER_OBSERVATION_ZONE_HPP
  25 #define XCSOAR_RENDER_OBSERVATION_ZONE_HPP
  26
  27 struct TaskLook;
  28 struct AirspaceLook;
  29 class Canvas;
  30 class Projection;
  31 struct AirspaceRendererSettings;
  32 class ObservationZonePoint;
  33
  34 /** Utility class to render an ObzervationZonePoint to a canvas */
  35 class OZRenderer {
  36 public:
  37   enum Layer {
  38     /** the background shade */
  39     LAYER_SHADE,
  40
  41     /** the inactive boundaries */
  42     LAYER_INACTIVE,
  43
  44     /** the active boundaries */
  45     LAYER_ACTIVE,
  46   };
  47
  48 protected:
  49   const TaskLook &task_look;
  50   const AirspaceLook &airspace_look;
  51   const AirspaceRendererSettings &settings;
  52
  53 public:
  54   OZRenderer(const TaskLook &task_look, const AirspaceLook &airspace_look,
  55              const AirspaceRendererSettings &_settings);
  56
  57   void Draw(Canvas &canvas, Layer _layer, const Projection &projection,
  58             const ObservationZonePoint &oz, int offset);
  59
  60 private:
  61   /**
  62    * Configure brush and pen on the Canvas for the current layer.
  63    *
  64    * @param offset the offset of this task point to the current task
  65    * point; 0 means it is the current task point, a negative value
  66    * means it is a "past" task point
  67    * @return false if nothing is to be drawn in this layer
  68    */
  69   void Prepare(Canvas &canvas, Layer layer, int offset) const;
  70
  71   /**
  72    * Cleans up the settings after drawing has been finished.  This
  73    * method must be invoked if draw_style() has returned true.
  74    */
  75   void Finish(Canvas &canvas, Layer layer) const;
  76 };
  77
  78 #endif