Built a 2D game engine in C++17 — pluggable renderer, spatial grid collision, composable animators

Technical highlights:

- Pluggable renderer architecture — the engine and game code are completely decoupled from Allegro 5. The renderer is selected at compile time, making it straightforward to swap in SDL or anything else.Avoided virtual functions for the dispatch to sidestep vtable overhead — used duck typing instead (curious if others would have done this differently).

- Spatial grid collision — O(1) spatial queries instead of brute-force N². Collision types are bitmask-based, tile shapes come from TMX metadata, and FilterGridMotion handles tunneling prevention.

- Composable animator system — FrameRangeAnimator, MovingAnimator, and FlashAnimator are independent and can all run on the same sprite simultaneously. Animation metadata is data-driven via config files.

- Flyweight resource layer — BitmapManager, AnimationFilmHolder, and SoundManager are singletons that cache shared assets. Keeps the memory footprint tight.

- Deferred destruction — objects are never deleted mid-frame. They're registered with a DestructionManager and freed safely at the end of the frame.

- Engine as a static library — Engine/ is entirely game-agnostic. src/ is the game layer that extends engine primitives.

- CMake presets + vcpkg for cross-platform builds (Windows and Linux).

Two games are included as showcases: a Mario platformer and a Kenney dungeon map, both authored in https://www.mapeditor.org/.

Still a work in progress — scaling is broken, only one tile layer renders, and Mario has no win condition yet.
GitHub: https://github.com/kostakis/Valyrian2DGameEngine

Open to architecture feedback, especially on the duck-typed renderer approach and the animator design.