src/Engine/Route/ReachResult.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_REACH_RESULT_HPP
  25 #define XCSOAR_REACH_RESULT_HPP
  26
  27 #include "Rough/RoughAltitude.hpp"
  28
  29 #include <stdint.h>
  30 #include <stdlib.h>
  31
  32 /**
  33  * The result of a reach calculation.
  34  */
  35 struct ReachResult {
  36   enum class Validity : uint8_t {
  37     INVALID,
  38     VALID,
  39     UNREACHABLE,
  40   };
  41
  42   /**
  43    * The arrival altitude for straight glide, ignoring terrain
  44    * obstacles.
  45    */
  46   RoughAltitude direct;
  47
  48   /**
  49    * The arrival altitude considering detour to avoid terrain
  50    * obstacles.  This attribute may only be used if #terrain_valid is
  51    * #VALID.
  52    */
  53   RoughAltitude terrain;
  54
  55   /**
  56    * This attribute describes whether the #terrain attribute is valid.
  57    */
  58   Validity terrain_valid;
  59
  60   void Clear() {
  61     direct = terrain = -1;
  62     terrain_valid = Validity::INVALID;
  63   }
  64
  65   bool IsReachableDirect() const {
  66     return direct.IsPositive();
  67   }
  68
  69   bool IsReachableTerrain() const {
  70     return terrain_valid == Validity::VALID && terrain.IsPositive();
  71   }
  72
  73   bool IsDeltaConsiderable() const {
  74     if (terrain_valid != Validity::VALID)
  75       return false;
  76
  77     const int delta = abs((int)direct - (int)terrain);
  78     return delta >= 10 && delta * 100 / (int)direct > 5;
  79   }
  80
  81   bool IsReachRelevant() const {
  82     return terrain_valid == Validity::VALID && terrain != direct;
  83   }
  84
  85   void Add(RoughAltitude delta) {
  86     direct += delta;
  87     terrain += delta;
  88   }
  89
  90   void Subtract(RoughAltitude delta) {
  91     direct -= delta;
  92     terrain -= delta;
  93   }
  94 };
  95
  96 #endif