LuaVector2

Simple 2D-vector library for Lua, created for generic purposes

Features

• Basic vector math
• Distance between vectors (linear & square) & vector normalizing
• Computing the angle between the vector amd the X axis or another vector and vice versa
• Dot production
• Cross production (as 3 component table) and its Z component
• Comparing vectors & one vector's values
• Vector rounding
• Unpacking & concatenating vectors like tables
• Copying vectors and overriding their values
• Constant vectors
• Adaptation for math or games/graphics (inversed Y axis)

Creating vectors

There are 3 methods to define a new vector:

• With its X and Y coordinates (LuaVector2.new(x, y))
• With an angle (in radians) and a vector length (LuaVector2.fromAngle(angle, length)). Optionally, it takes the basic vector, showing the direction of 0 radians, as the third argument.
• Copying a constant or already existing vector (LuaVector2.copy(src) or src:copy())

Copying vector, excracting and overriding values

Each vector has 2 compoments: X component (['x'] or [1]) and Y component (['y'] or [2]). You can unpack the vector (LuaVector2:unpack()), override its components (LuaVector2:override(x, y)) or copy it (LuaVector2:copy()).

Constant Vectors

Directional vectors:

• LuaVector2.RIGHT = {1, 0}
• LuaVector2.DOWN = {0, -1}
• LuaVector2.LEFT = {1, 0}
• LuaVector2.UP = {0, 1}
  Unit vectors:
• LuaVector2.ZERO = {0, 0}
• LuaVector2.ONE = {1, 1}
• LuaVector2.INF = {1/0, 1/0}
• LuaVector2.NEG_ONE = {-1, -1}
• LuaVector2.NEG_INF = {-1/0, -1/0}
  Note: the vertical directions where took with the direct Y axis. Most game engines (like http://love2d.org) and other graphic libraries/programs use the inverted Y axis, which can be enabled with changing Vector2.yScale = 1 to Vector2.yScale = -1 inside the library code. Changing this option after initialization will change the function behaviour, but not the constant vectors, so be careful while using them!

License

The library are destributed under the MIT License (see the library file).