From df6d323e42cdf3c38dbcee34b73e0d746b5bc4ba Mon Sep 17 00:00:00 2001
From: Jan Mrna <mj370@protonmail.com>
Date: Sun, 12 Oct 2025 16:19:38 +0200
Subject: [PATCH] Fix collision radius size when zooming

---
 cpp/src/camera.hpp   | 12 ++++++++++++
 cpp/src/gameloop.cpp |  7 ++++---
 2 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/cpp/src/camera.hpp b/cpp/src/camera.hpp
index f57b441..b321baa 100644
--- a/cpp/src/camera.hpp
+++ b/cpp/src/camera.hpp
@@ -15,6 +15,18 @@ public:
   WorldPos   WindowToWorld(WindowPos)      const;
   WindowSize WorldToWindowSize(WorldSize)  const;
   WorldSize  WindowToWorldSize(WindowSize) const;
+  
+  template <typename T>
+  requires std::floating_point<T>
+  T WindowToWorldSize(T window_size) const {
+    return window_size / static_cast<T>(m_Zoom);
+  }
+  
+  template <typename T>
+  requires std::floating_point<T>
+  T WorldToWindowSize(T world_size) const {
+    return world_size * static_cast<T>(m_Zoom);
+  }
 
 private:
   // TODO this should be replaced with a matrix
diff --git a/cpp/src/gameloop.cpp b/cpp/src/gameloop.cpp
index 4cf4097..81aad3e 100644
--- a/cpp/src/gameloop.cpp
+++ b/cpp/src/gameloop.cpp
@@ -43,13 +43,14 @@ void GameLoop::Draw() {
   // draw all the entities (player etc)
   for (auto &entity : m_Game->GetEntities()) {
     const auto &camera = m_Game->GetCamera();
-    auto entity_pos_window = camera.WorldToWindow(entity->GetPosition());
-    m_Window->DrawSprite(entity_pos_window,
+    auto entity_pos = camera.WorldToWindow(entity->GetPosition());
+    m_Window->DrawSprite(entity_pos,
                          entity->GetSprite(),
                          camera.GetZoom());
     if (entity->IsCollisionBoxVisible())
     {
-      m_Window->DrawCircle(entity_pos_window, entity->GetCollisionRadius());
+      float collision_radius = camera.WorldToWindowSize(entity->GetCollisionRadius());
+      m_Window->DrawCircle(entity_pos, collision_radius);
     }
   }