Coordinate system

  o Right-handed
  o Z-Up

  Negative X goes left, positive X goes right
  Negative Y goes backwards, positive Y goes forwards
  Negative Z goes down, positive Z goes up

Arguments for:

  - Positive values are intuitive: right, up, forwards (whereas in Y-up, one
    axis will always be counter-intuitive, eg. positive Z means backwards)

  - For the real world, the X/Y plane is the one we move around on and movement
    on Z is more exotic (requiring jumps or ladders)

  - Architects (whose work is more closely related to 3D games than mathematicians
    plotting curves) use this system. Mathematicians can simply assume their curves
    lie on the ground: more means farther instead of higher - smaller compromise.

  - Maps better to polar coordinate systems (Z = Z, R = Y versus Z = Y and R = -Z)

  - Blender is Z-up, 3ds Max is Z-up, Unreal is Z-up

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  o Right-handed
  o Y-Up

  Negative X goes left, positive X goes right
  Negative Y goes down, positive Y goes up
  Negative Z goes forward, positive Z goes backward

Arguments for:

  - Maya is Y-up, Unity is Y-up

Arguments against:

  - Vector2's directional constants (Up = {0,1}; Down = {0,-1}) would not translate
    well into 3D space (a zero needs to be added inbetween or 2D up becomes forward,
    to avoid this, the constants need to be named Forward and Backward)


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// ExtrapolationMode
//   Clamp
//   Linear
//   Repeat
//   PingPing