Godot 3's renderer design
While scrolling fast through the long document, my eyes immediately focused on "Wait, why not Vulkan or DirectX12?" :-Dtl;dr "At the end of the day, the use case where Vulkan and DirectX12 make the most sense is when you have hundreds of thousands of objects, which are all different (different geometry, textures, etc.), and which move. This is a difficult use case to achieve, even willingly."