Added MirrorSystem

This is really just for letting one sprite mirror another's movement and animation. I tried doing it in the BehaviourSystem, but you get stuttering if you do it earlier in the loop than the CharacterSystem, so I ended up having to make a new system just for this thing that will not happen very often.

10 files changed, 94 insertions, 0 deletions

@@ -55,6 +55,7 @@ add_executable(tanetane
   src/script_system.cpp
   src/effect_system.cpp
   src/behaviour_system.cpp
+  src/mirror_system.cpp
 )
 
 set_property(TARGET tanetane PROPERTY CXX_STANDARD 17)
@@ -65,6 +65,19 @@ inline Direction oppositeDirection(Direction value) {
   }
 }
 
+inline Direction directionMirroredVertically(Direction value) {
+  switch (value) {
+    case Direction::up: return Direction::down;
+    case Direction::up_right: return Direction::down_right;
+    case Direction::right: return Direction::right;
+    case Direction::down_right: return Direction::up_right;
+    case Direction::down: return Direction::up;
+    case Direction::down_left: return Direction::up_left;
+    case Direction::left: return Direction::left;
+    case Direction::up_left: return Direction::down_left;
+  }
+}
+
 inline Direction directionFacingPoint(vec2i point) {
   double theta = atan2(-point.y(), point.x());
   theta /= M_PI;
@@ -76,6 +76,11 @@ void Game::loadMap(std::string filename) {
     if (!p.enclosureZone.empty()) {
       getSprite(spriteId).enclosureZone = p.enclosureZone;
     }
+    if (p.mirrorType != MirrorType::None) {
+      getSprite(spriteId).mirrorType = p.mirrorType;
+      getSprite(spriteId).mirrorAxis = p.mirrorAxis;
+      getSprite(spriteId).mirroredSpriteId = getSpriteByAlias(p.spriteToMirror);
+    }
   }
 
   for (const Trigger& t : map_->getTriggers()) {
@@ -14,6 +14,7 @@
 #include "script_system.h"
 #include "effect_system.h"
 #include "behaviour_system.h"
+#include "mirror_system.h"
 
 void loop(Renderer& renderer, std::mt19937& rng) {
   Game game(renderer, rng);
@@ -22,6 +23,7 @@ void loop(Renderer& renderer, std::mt19937& rng) {
   game.emplaceSystem<InputSystem>();
   game.emplaceSystem<BehaviourSystem>();
   game.emplaceSystem<CharacterSystem>();
+  game.emplaceSystem<MirrorSystem>();
   game.emplaceSystem<AnimationSystem>();
   game.emplaceSystem<CameraSystem>();
   game.emplaceSystem<MessageSystem>();
@@ -111,6 +111,14 @@ Map::Map(std::string_view name) : name_(name) {
               p.enclosureZone = property.getStringValue();
             } else if (property.getName() == "movementSpeed") {
               p.movementSpeed = property.getIntValue();
+            } else if (property.getName() == "mirror") {
+              if (property.getStringValue() == "vertical") {
+                p.mirrorType = MirrorType::Vertical;
+              }
+            } else if (property.getName() == "mirrorAxis") {
+              p.mirrorAxis = property.getIntValue();
+            } else if (property.getName() == "mirrorSprite") {
+              p.spriteToMirror = property.getStringValue();
             }
           }
 
@@ -32,6 +32,9 @@ struct Prototype {
   int movementSpeed = -1;
   std::string enclosureZone;
   bool masked = false;
+  MirrorType mirrorType = MirrorType::None;
+  int mirrorAxis = 0;
+  std::string spriteToMirror;
 };
 
 struct Trigger {
@@ -0,0 +1,29 @@
+#include "mirror_system.h"
+#include "game.h"
+#include "transform_system.h"
+#include "animation_system.h"
+#include "vector.h"
+#include "sprite.h"
+
+void MirrorSystem::tick(double dt) {
+  for (int spriteId : game_.getSprites()) {
+    Sprite& sprite = game_.getSprite(spriteId);
+    if (!sprite.paused) {
+      switch (sprite.mirrorType) {
+        case MirrorType::None: break;
+        case MirrorType::Vertical: {
+          Sprite& mirroredSprite = game_.getSprite(sprite.mirroredSpriteId);
+
+          vec2i mirroredLoc = mirroredSprite.loc;
+          mirroredLoc.y() = 2 * sprite.mirrorAxis - mirroredLoc.y();
+
+          game_.getSystem<TransformSystem>().moveSprite(spriteId, mirroredLoc);
+          game_.getSystem<AnimationSystem>().setSpriteAnimation(spriteId, mirroredSprite.animationName);
+          game_.getSystem<AnimationSystem>().setSpriteDirection(spriteId, directionMirroredVertically(mirroredSprite.dir));
+
+          break;
+        }
+      }
+    }
+  }
+}
@@ -0,0 +1,22 @@
+#ifndef MIRROR_SYSTEM_H_0BA755A8
+#define MIRROR_SYSTEM_H_0BA755A8
+
+#include "system.h"
+
+class Game;
+
+class MirrorSystem : public System {
+public:
+
+  static constexpr SystemKey Key = SystemKey::Mirror;
+
+  explicit MirrorSystem(Game& game) : game_(game) {}
+
+  void tick(double dt) override;
+
+private:
+
+  Game& game_;
+};
+
+#endif /* end of include guard: MIRROR_SYSTEM_H_0BA755A8 */
@@ -48,6 +48,11 @@ enum class BehaviourType {
   Path
 };
 
+enum class MirrorType {
+  None,
+  Vertical
+};
+
 struct Movement {
   vec2i pos;
   Direction dir;
@@ -123,6 +128,11 @@ public:
   vec2i pathfindingDestination;
   bool cardinalDirectionsOnly = false;
   std::deque<PathfindingInstruction> path;
+
+  // Mirror
+  MirrorType mirrorType = MirrorType::None;
+  int mirroredSpriteId = -1;
+  int mirrorAxis = 0;
 };
 
 #endif /* end of include guard: SPRITE_H_70503825 */
@@ -7,6 +7,7 @@ enum class SystemKey {
   Input,
   Behaviour,
   Character,
+  Mirror,
   Animation,
   Camera,
   Message,