Add built-in ability jump_over_water

Closes #530.

changelog.txt

@@ -22,6 +22,7 @@ Engine changes
 * Improve the performance of custom entity collisions.
 * Improve the performance of collisions by using a quadtree.
 * Entities far from the camera are no longer suspended.
+* The hero no longer automatically jumps when arriving on water (#530).
 * Destinations can now set to update or not the starting location (#819).
 * Teletransporters on the side of the map now work on all layers (#850).
 * Streams can now have a speed of zero (#496).
@@ -60,6 +61,7 @@ Changes that introduce incompatibilities:
 * chest:on_empty() is replaced by chest:on_opened(treasure) (#483).
 * Enemy ranks no longer exists, set_hurt_style() needs to be called (#449).
 * Items with amount now have a default max amount of 1000 (#688).
+* New ability "jump_over_water" in game:get/set_ability(), off by default (#530).
 * Fix hero state name "freezed", renamed it to "frozen" (#813).
 * Fix map:get_entities() not returning the hero (#670).
 * map:get_camera_position() is now deprecated, use camera:get_position().

include/solarus/Ability.h

@@ -1,16 +1,16 @@
 /*
  * Copyright (C) 2006-2016 Christopho, Solarus - http://www.solarus-games.org
- * 
+ *
  * Solarus is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation, either version 3 of the License, or
  * (at your option) any later version.
- * 
+ *
  * Solarus is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  * GNU General Public License for more details.
- * 
+ *
  * You should have received a copy of the GNU General Public License along
  * with this program. If not, see <http://www.gnu.org/licenses/>.
  */
@@ -31,6 +31,8 @@ enum class Ability {
   SHIELD,                 /**< Allows to stop attacks from enemies. */
   LIFT,                   /**< Lifting destructible objects. */
   SWIM,                   /**< Swimming in deep water. */
+  JUMP_OVER_WATER,        /**< Automatically jumping when arriving in water
+                           * without the SWIM ability. */
   RUN,                    /**< Running faster. */
   DETECT_WEAK_WALLS,      /**< Be notified of weak walls nearby. */
 };

include/solarus/Savegame.h

@@ -77,6 +77,7 @@ class SOLARUS_API Savegame: public ExportableToLua {
     static const std::string KEY_ABILITY_SHIELD;
     static const std::string KEY_ABILITY_LIFT;
     static const std::string KEY_ABILITY_SWIM;
+    static const std::string KEY_ABILITY_JUMP_OVER_WATER;
     static const std::string KEY_ABILITY_RUN;
     static const std::string KEY_ABILITY_DETECT_WEAK_WALLS;
     static const std::string KEY_ABILITY_GET_BACK_FROM_DEATH;

src/AbilityInfo.cpp

@@ -28,6 +28,7 @@ const EnumInfo<Ability>::names_type EnumInfoTraits<Ability>::names = {
     { Ability::SHIELD, "shield" },
     { Ability::LIFT, "lift" },
     { Ability::SWIM, "swim" },
+    { Ability::JUMP_OVER_WATER, "jump_over_water" },
     { Ability::RUN, "run" },
     { Ability::DETECT_WEAK_WALLS, "detect_weak_walls" }
 };

src/Equipment.cpp

@@ -562,8 +562,11 @@ std::string Equipment::get_ability_savegame_variable(Ability ability) const {
     case Ability::LIFT:
       return Savegame::KEY_ABILITY_LIFT;
 
-    case Ability::SWIM:
-      return Savegame::KEY_ABILITY_SWIM;
+  case Ability::SWIM:
+    return Savegame::KEY_ABILITY_SWIM;
+
+  case Ability::JUMP_OVER_WATER:
+    return Savegame::KEY_ABILITY_JUMP_OVER_WATER;
 
     case Ability::RUN:
       return Savegame::KEY_ABILITY_RUN;

src/Savegame.cpp

@@ -65,6 +65,8 @@ const std::string Savegame::KEY_ABILITY_SWORD_KNOWLEDGE =
 const std::string Savegame::KEY_ABILITY_SHIELD = "_ability_shield";    /**< Protection level. */
 const std::string Savegame::KEY_ABILITY_LIFT = "_ability_lift";        /**< Lift level. */
 const std::string Savegame::KEY_ABILITY_SWIM = "_ability_swim";        /**< Swim level. */
+const std::string Savegame::KEY_ABILITY_JUMP_OVER_WATER =
+    "_ability_jump_over_water";                                        /**< Jump over water level. */
 const std::string Savegame::KEY_ABILITY_RUN = "_ability_run";          /**< Run level. */
 const std::string Savegame::KEY_ABILITY_DETECT_WEAK_WALLS =
     "_ability_detect_weak_walls";                                      /**< Weak walls detection level. */

src/entities/Hero.cpp

@@ -2175,22 +2175,29 @@ void Hero::notify_game_over_finished() {
  */
 void Hero::start_deep_water() {
 
+  const bool can_swim = get_equipment().has_ability(Ability::SWIM);
+  const bool can_jump_over_water = get_equipment().has_ability(Ability::JUMP_OVER_WATER);
+
   if (!get_state().is_touching_ground()) {
-    // plunge into the water
+    // Entering water from above the ground
+    // (e.g. after a jump).
     set_state(new PlungingState(*this));
   }
   else {
-    // move to state swimming or jumping
-    if (get_equipment().has_ability(Ability::SWIM)) {
+    // Entering water normally (e.g. by walking).
+    if (can_swim) {
       set_state(new SwimmingState(*this));
     }
-    else {
+    else if (can_jump_over_water) {
       int direction8 = get_wanted_movement_direction8();
       if (direction8 == -1) {
         direction8 = get_animation_direction() * 2;
       }
       start_jumping(direction8, 32, false, true);
     }
+    else {
+      set_state(new PlungingState(*this));
+    }
   }
 }