Emulate Higher Precision

[waylonflinn]

Some hardware doesn't support 32-bit precision. We should emulate higher precision, where necessary.

• Double Precision in OpenGL and WebGL
• Heavy computing with GLSL – Part 2: Emulated double precision

This technique could also be useful for getting 64-bit precision out of WebGL.

• Heavy computing with GLSL – Part 5: Emulated quadruple precision

[waylonflinn]

More useful references for compatibility:

• How To Write Portable WebGL
• WebGL Stats
• Browser Leaks