Why would this replace OpenGl? Opengl is lower level interface, with all kinds of memory management problems caused by C language. GameApi instead uses C++ and can significantly improve the steps required to create games. Instead of allocating buffers with malloc(), GameApi does all buffer allocation automatically, calculating the required amount of memory without programmer needing to specify it explicitly. Data structures required for high performance graphics is hidden behind the api, creating more power for programmers. All the small details no longer need to be handled by programmer explicitly, since the library handles it automatically. Lazy evaluation and pure functions are borrowed from functional programming languages, bringing state of the art primitives for games programmers.
Games rely on hardware acceleration to get performance. This usually involves moving all the heavy lifting from the frame loop to the precalculation step in the game initialization. This way all the operations required in the critical game loop are hardware accelerated primitives. GameApi's approach is to carefully document all the dependencies in the api, in order to make all hidden dependencies explicit. All combinations of the provided primitives are working, and the functionality is split to small pieces which makes it easier to move unwanted functionality outside of frame loop.
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