Modified version of Sony's open sourced header-only vector and matrix math library. I've uploaded a copy here so it can be easily submoduled on other projects.

The main differences from the original library released by Sony:

• Removed deprecated SPU/PPU implementations that only targeted PS3/PowerPC.
• Removed the C interfaces - the C++ interface is much nicer to use with operator overloads, return by val, etc.
• Massive namespace cleanup. Removed or replaced most macros with functions and constants.
• Better compliance with strict aliasing rules.
• Added portable macros for alignment annotations to remove some #ifdefs.
• Internal SSE helper code moved to a separate header - other files also renamed.
• Removed the Aos/Soa sub-namespaces, since the Soa implementations were only available for SPU.
• The library now includes only the generic scalar version and the x86/64 SSE intrinsics version.
• Added an unpadded Vector2 and Point2 to also support basic 2D vector maths. These are always scalar mode (size = 2 floats).
• All you need to do is include the public header file vectormath.hpp. It will expose the relevant parts of the library for you and try to select the SSE implementation if supported.

 Vector Math library for 3-D linear algebra (vector, matrix, quaternion)
   SIMD support for SSE. Also includes generic multi-platform scalar version.

   Copyright (C) 2006, 2007 Sony Computer Entertainment Inc.
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