What are some alternatives?
When comparing HaxeFlixel and OpenGL, you can also consider the following products
MonoGame - MonoGame is an open source implementation of the Microsoft XNA 4 Framework.
Vulkan - Vulkan is a new generation graphics and compute API that provides high-efficiency, cross-platform access to modern GPUs used in a wide variety of devices from PCs and consoles to mobile phones and embedded platforms.
RPG Maker - Make your own PC game with RPG Maker. Our easy to use tools are simple enough for a child, and powerful enough for a developer. Try it free today!
SDL - Simple DirectMedia Layer is a cross-platform multimedia library designed to provide low level...
AppGameKit - AppGameKit is a game development platform for mobile devices.