From 82eb2e25391089ed11424e4b05d2c8875cded93d Mon Sep 17 00:00:00 2001
From: Jan Mrna <mj370@protonmail.com>
Date: Sat, 27 Sep 2025 13:49:17 +0200
Subject: [PATCH] Move entities implementation to entity.cpp

---
 cpp/Makefile           |   2 +-
 cpp/src/entities.cpp   |  66 ++++++++++++++++++
 cpp/src/entities.hpp   | 149 ++++++++++-------------------------------
 cpp/src/user_input.hpp |   1 +
 4 files changed, 104 insertions(+), 114 deletions(-)

diff --git a/cpp/Makefile b/cpp/Makefile
index 305c39a..d7903b6 100644
--- a/cpp/Makefile
+++ b/cpp/Makefile
@@ -3,7 +3,7 @@ all: test pathfinding
 # TODO linter?
 
 pathfinding: src/main.cpp src/array.hpp src/sprite.cpp
-	g++ -Wall -ggdb3 -lSDL3 -lSDL3_image -std=c++23 -lGLEW -lGL -o pathfinding src/main.cpp src/sprite.cpp
+	g++ -Wall -ggdb3 -lSDL3 -lSDL3_image -std=c++23 -lGLEW -lGL -o pathfinding src/main.cpp src/sprite.cpp src/entities.cpp
 
 test: src/test.cpp src/array.hpp
 	g++ -Wall -Wextra -Wpedantic -ggdb3 -std=c++23 -lgtest -o test src/test.cpp
diff --git a/cpp/src/entities.cpp b/cpp/src/entities.cpp
index e69de29..0122f12 100644
--- a/cpp/src/entities.cpp
+++ b/cpp/src/entities.cpp
@@ -0,0 +1,66 @@
+#include <memory>
+
+#include "entities.hpp"
+
+#include "log.hpp"
+#include "math.hpp"
+#include "sprite.hpp"
+
+Entity::Entity(WorldPos position) : m_Position(position) {
+  LOG_DEBUG("spawning entity at position ", position);
+}
+
+std::ostream &operator<<(std::ostream &os, const Entity &obj) {
+  static constexpr std::array<std::string_view,
+                              static_cast<size_t>(Entity::Type::COUNT)>
+      type_name{"NONE", "PLAYER", "TILE"};
+  size_t idx = static_cast<size_t>(obj.GetType());
+  assert(idx < type_name.size());
+  os << type_name[idx];
+  return os;
+}
+
+void Entity::ZeroActualVelocityInDirection(WorldPos direction) {
+  // Vectors e1, e2 form the basis for a local coord system,
+  // where e1 is formed by the direction where we want to zero-out
+  // the velocity, and e2 is the orthogonal vector.
+  // Scalars q1, q2 are coordinates for e1, e2 basis.
+  WorldPos e1 = direction.normalized();
+  WorldPos e2 = e1.orthogonal();
+
+  // q1 * e1 + q2 * e2 = v, from this follows:
+  auto &v = GetActualVelocity();
+  float q2 = (v.y * e1.x - v.x * e1.y) / (e2.y * e1.x - e2.x * e1.y);
+  float q1 = (v.x - q2 * e2.x) / e1.x;
+
+  // We then zero-out the q1, but only if it's positive - meaning
+  // it is aiming in the direction of "direction", not out.
+  // (otherwise we're not able to move out from collision with
+  // another object)
+  if (q1 > 0.0f) {
+    SetActualVelocity(q2 * e2);
+  }
+}
+
+void Entity::Update(float time_delta) {
+  m_Position += m_ActualVelocity * time_delta;
+}
+
+Player::Player() {
+  LOG_DEBUG(".");
+  if (m_Sprite == nullptr) {
+    LoadResources();
+  }
+}
+
+Sprite &Player::GetSprite() {
+  assert(m_Sprite != nullptr);
+  return *m_Sprite;
+}
+
+void Player::LoadResources() {
+  m_Sprite =
+      std::make_unique<Sprite>("resources/player.png", WorldPos{38.0f, 46.0f});
+}
+
+std::unique_ptr<Sprite> Player::m_Sprite;
diff --git a/cpp/src/entities.hpp b/cpp/src/entities.hpp
index a195662..bed7204 100644
--- a/cpp/src/entities.hpp
+++ b/cpp/src/entities.hpp
@@ -6,141 +6,71 @@
 #include <memory>
 #include <string_view>
 
+#include "log.hpp"
 #include "math.hpp"
 #include "sprite.hpp"
-#include "log.hpp"
 
 class Entity {
 public:
   enum class Type : std::uint8_t {
     NONE,
     PLAYER,
-    WALL,
     TILE,
     COUNT // must be last
   };
 
-  Entity(Vec2D<float> position = {0.0f, 0.0f}) : m_Position(position) {
-    LOG_DEBUG("spawning entity at position ", position);
-  }
+  Entity(WorldPos position = {0.0f, 0.0f});
+  Entity(const Entity &) = delete;
+  Entity &operator=(const Entity &) = delete;
+  Entity(Entity &&) = delete;
+  Entity &operator=(Entity &&) = delete;
 
-  friend std::ostream &operator<<(std::ostream &os, const Entity &obj) {
-    static constexpr std::array<std::string_view,
-                                static_cast<size_t>(Entity::Type::COUNT)>
-        type_name{"NONE", "PLAYER", "WALL", "TILE"};
-    size_t idx = static_cast<size_t>(obj.GetType());
-    assert(idx < type_name.size());
-    os << type_name[idx];
-    return os;
-  }
+  friend std::ostream &operator<<(std::ostream &os, const Entity &obj);
 
   virtual Sprite &GetSprite() = 0;
   virtual constexpr float GetCollisionRadius() const = 0;
-  virtual constexpr float GetCollisionRadiusSquared() {
-    return GetCollisionRadius() * GetCollisionRadius();
-  }
-
   virtual constexpr Type GetType() const = 0;
-  void SetFlagExpired() { m_FlagExpired = true; }
-  bool IsFlaggedExpired() { return m_FlagExpired; }
-
-  const Vec2D<float> &GetPosition() const { return m_Position; }
-  void SetPosition(Vec2D<float> new_pos) { m_Position = new_pos; }
-
-  const Vec2D<float> &GetActualVelocity() const { return m_ActualVelocity; }
-  const Vec2D<float> &GetRequestedVelocity() const {
-    return m_RequestedVelocity;
-  }
-  void SetActualVelocity(const Vec2D<float> &new_velocity) {
-    m_ActualVelocity = new_velocity;
-  }
-  void SetRequestedVelocity(const Vec2D<float> &new_velocity) {
-    m_RequestedVelocity = new_velocity;
-  }
-
-  void ZeroActualVelocityInDirection(Vec2D<float> direction) {
-    // Vectors e1, e2 form the basis for a local coord system,
-    // where e1 is formed by the direction where we want to zero-out
-    // the velocity, and e2 is the orthogonal vector.
-    // Scalars q1, q2 are coordinates for e1, e2 basis.
-    Vec2D<float> e1 = direction.normalized();
-    Vec2D<float> e2 = e1.orthogonal();
-
-    // q1 * e1 + q2 * e2 = v, from this follows:
-    auto &v = GetActualVelocity();
-    float q2 = (v.y * e1.x - v.x * e1.y) / (e2.y * e1.x - e2.x * e1.y);
-    float q1 = (v.x - q2 * e2.x) / e1.x;
-
-    // We then zero-out the q1, but only if it's positive - meaning
-    // it is aiming in the direction of "direction", not out.
-    // (otherwise we're not able to move out from collision with
-    // another object)
-    if (q1 > 0.0f) {
-      SetActualVelocity(q2 * e2);
-    }
-  }
-
-  virtual void Update(float time_delta) {
-    m_Position += m_ActualVelocity * time_delta;
-  }
-
   virtual bool IsMovable() const = 0;
   virtual bool IsCollidable() const = 0;
 
+  virtual void Update(float time_delta);
+
+  virtual constexpr float GetCollisionRadiusSquared() const {
+    return GetCollisionRadius() * GetCollisionRadius();
+  }
+
+  void SetFlagExpired() { m_FlagExpired = true; }
+  bool IsFlaggedExpired() const { return m_FlagExpired; }
+
+  const WorldPos &GetPosition() const { return m_Position; }
+  void SetPosition(WorldPos new_pos) { m_Position = new_pos; }
+
+  const WorldPos &GetActualVelocity() const { return m_ActualVelocity; }
+  const WorldPos &GetRequestedVelocity() const { return m_RequestedVelocity; }
+  void SetActualVelocity(const WorldPos &new_velocity) {
+    m_ActualVelocity = new_velocity;
+  }
+  void SetRequestedVelocity(const WorldPos &new_velocity) {
+    m_RequestedVelocity = new_velocity;
+  }
+
+  void ZeroActualVelocityInDirection(WorldPos direction);
+
 protected:
-  Vec2D<float> m_Position;
-  Vec2D<float> m_ActualVelocity;
-  Vec2D<float> m_RequestedVelocity;
+  WorldPos m_Position;
+  WorldPos m_ActualVelocity;
+  WorldPos m_RequestedVelocity;
 
 private:
   bool m_FlagExpired = false;
   static constexpr float m_CollisionRadiusSq = 1000.0f;
 };
 
-class Wall final : public Entity {
-public:
-  Wall(Vec2D<float> pos = {0.0f, 0.0f}) : Entity(pos) {
-    LOG_DEBUG(".");
-    if (m_Sprite == nullptr) {
-      LoadResources();
-    }
-  }
-  Wall(const Wall &x) = delete;
-  Wall(Wall &&x) = delete;
-
-  Sprite &GetSprite() override {
-    assert(m_Sprite != nullptr);
-    return *m_Sprite;
-  }
-  constexpr Entity::Type GetType() const override { return Entity::Type::WALL; }
-  constexpr float GetCollisionRadius() const override { return 50.0f; }
-  bool IsMovable() const override { return false; }
-  bool IsCollidable() const override { return true; }
-
-private:
-  void LoadResources() {
-    m_Sprite = std::make_unique<Sprite>("resources/wall.png",
-                                        Vec2D<float>{50.0f, 50.0f});
-  }
-  static std::unique_ptr<Sprite> m_Sprite;
-};
-std::unique_ptr<Sprite> Wall::m_Sprite;
-
 class Player final : public Entity {
 public:
-  Player() {
-    LOG_DEBUG(".");
-    if (m_Sprite == nullptr) {
-      LoadResources();
-    }
-  }
-  Player(const Player &x) = delete;
-  Player(Player &&x) = delete;
+  Player();
 
-  Sprite &GetSprite() override {
-    assert(m_Sprite != nullptr);
-    return *m_Sprite;
-  }
+  Sprite &GetSprite() override;
 
   constexpr Entity::Type GetType() const override {
     return Entity::Type::PLAYER;
@@ -150,13 +80,6 @@ public:
   bool IsCollidable() const override { return true; }
 
 private:
-  void LoadResources() {
-    m_Sprite = std::make_unique<Sprite>("resources/player.png",
-                                        Vec2D<float>{38.0f, 46.0f});
-  }
+  void LoadResources();
   static std::unique_ptr<Sprite> m_Sprite;
 };
-
-std::unique_ptr<Sprite> Player::m_Sprite;
-
-
diff --git a/cpp/src/user_input.hpp b/cpp/src/user_input.hpp
index 425cefd..c67aae1 100644
--- a/cpp/src/user_input.hpp
+++ b/cpp/src/user_input.hpp
@@ -4,6 +4,7 @@
 #include <vector>
 #include <map>
 #include <string>
+#include <expected>
 
 #include "math.hpp"
 #include "log.hpp"