More OpenGL Work!

I was playing more with OpenGL, and decided that I could re-write my existing 3D back-end to be far more flexible! After looking over asset libraries for quite some time, I decided that it would be a good idea to try and incorporate a flexible, reliable framework for reading asset data. I eventually settled on Assimp. A cross-platform library for loading dozens of different 3D assets, animations, skeletons, and some texture formats! It was admittedly a bit of a pain to work through, but once compiled, it was easily incorporated. Pretty soon, I got my system loading .Md5 models (The format used in older versions of the Quake engine).

After I managed to get models loading, my next goal was animation. Skeletal animation is something I had never tried before, and frankly, I was a little afraid of it. It seems like a daunting task to begin with, especially considering the seemingly infinite number of possible skeletons and numerous model formats that could be loaded. Some model formats store their joint orientations in quaternion values, so I ended up having to write a quaternion to matrix conversion system on the back end in order to allow these formats to work! Eventually though, I got simple .Md5Anim files loading, and playing (sort of). With hours of struggle, and frustration, I finally figured it was a simple problem with multiplication order of matrices. In the end, I got these models playing arbitrary animations successfully!

This system supports almost any effect, shader, or camera setup imaginable, and is flexible enough to implement a number of simple effects incredibly easily. So far, it does not support more advanced lighting features, such as shadows, but they can be added in quite simply.

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