Major Improvements
Fixes to Direct3D 9 and implementation of OpenGL3 context manager.
Major Direct3D 9 Changes
Custom sprite batching and 2D batching, etc.
Moved sprite_exists out of graphics system, it belonged in
universal_system/sprite_struct, also shelled an irrlicht graphics_system
More cleanup, moved background functions to universal system.
Merge branch 'master' of https://github.com/RobertBColton/enigma-dev
Removed irrlicht and other cleanup.
Fixed variable name conflict in d3d_model_load
Added fixes to d3d_model_load to make it work on Linux and set
OpenGL/OpenAL as default systems again until other shit is accomplished
just good enough to make this pull request mergeable for now.
Vastly improved the performance of Direct3D 9
Resolved issues with Direct3D 9
More cleanup and improved OpenGL 1.1 model struct.
Removed duplicate glew.c
Implemented missing get pixel functions.
Fixed texture stage alpha blending, the default is not set to mix with
per-vertex alpha like OpenGL does, resolved in the function texture_set
Readded all sprite drawing functions for Direct3D 9
Readded all background drawing functions to Direct3D 9
Readded all surface drawing functions to Direct3D 9
Added missing color arguments and missing surface tiled drawing functions.
Refactored graphics code to be reusable between systems with the new
batching system.
Added all unimplemented text drawing functions to Direct3D.