About

This is a part of my Audiosurf 2 scripting library.

Contents

vec3

Various helpers for working with 3D coordinates

vec3 = {}
do
	function vec3.add(a, b)       return {a[1] + b[1], a[2] + b[2], a[3] + b[3]} end
	function vec3.sub(a, b)       return {a[1] - b[1], a[2] - b[2], a[3] - b[3]} end
	function vec3.mulSingle(a, b) return {a[1] * b, a[2] * b, a[3] * b} end
	function vec3.divSingle(a, b) return {a[1] / b, a[2] / b, a[3] / b} end
	function vec3.assign(a, dest) dest[1], dest[2], dest[3] = a[1], a[2], a[3] end
	function vec3.copy(a)         return { a[1], a[2], a[3] } end
	function vec3.fromApi(a)      return { a.x, a.y, a.z } end

	local min, max = math.min, math.max
	function vec3.min(a, b)    return { min(a[1], b[1]), min(a[2], b[2]), min(a[3], b[3]) } end
	function vec3.max(a, b)    return { max(a[1], b[1]), max(a[2], b[2]), max(a[3], b[3]) } end

	-- returns 3 arrays of numbers: x, y, and z
	function vec3.transposeArray(vec3_array)
		local x, y, z = {}, {}, {}
		local v
		for i=1,#vec3_array do
			v = vec3_array[i]
			x[i], y[i], z[i] = v[1], v[2], v[3]
		end
		return x, y, z
	end

	function vec3.avg(a, b)       return {(a[1] + b[1]) / 2, (a[2] + b[2]) / 2, (a[3] + b[3]) / 2} end

	local sqrt = math.sqrt
	function vec3.len(a)          return sqrt(a[1]^2 + a[2]^2 + a[3]^2) end
	function vec3.lenSquared(a)   return a[1]^2 + a[2]^2 + a[3]^2 end
	function vec3.dist(a, b)      return sqrt((a[1] - b[1])^2 + (a[2] - b[2])^2 + (a[3] - b[3])^2) end

	local divSingle, len = vec3.divSingle, vec3.len
	function vec3.norm(a)         return divSingle(a, len(a)) end
	function vec3.setLen(a, b)    return divSingle(a, len(a) / b) end

	function vec3.neg(a)          return {-a[1], -a[2], -a[3]} end
end

vec2

Various helpers for working with 2D coordinates

vec2 = {}
do
	function vec2.add(a, b)       return {a[1] + b[1], a[2] + b[2]} end
	function vec2.sub(a, b)       return {a[1] - b[1], a[2] - b[2]} end
	function vec2.mulSingle(a, b) return {a[1] * b, a[2] * b} end
	function vec2.divSingle(a, b) return {a[1] / b, a[2] / b} end
	function vec2.assign(a, dest) dest[1], dest[2] = a[1], a[2] end
	function vec2.copy(a)         return { a[1], a[2] } end
	function vec2.fromApi(a)      return { a.x, a.y } end

	local min, max = math.min, math.max
	function vec2.min(a, b)    return { min(a[1], b[1]), min(a[2], b[2]) } end
	function vec2.max(a, b)    return { max(a[1], b[1]), max(a[2], b[2]) } end

	-- returns 2 arrays of numbers: x and y
	function vec2.transposeArray(vec2_array)
		local x, y = {}, {}
		local v
		for i=1,#vec2_array do
			v = vec2_array[i]
			x[i], y[i] = v[1], v[2]
		end
		return x, y
	end

	function vec2.avg(a, b)       return {(a[1] + b[1]) / 2, (a[2] + b[2]) / 2} end

	local sqrt = math.sqrt
	function vec2.len(a)          return sqrt(a[1]^2 + a[2]^2) end
	function vec2.lenSquared(a)   return a[1]^2 + a[2]^2 end
	function vec2.dist(a, b)      return sqrt((a[1] - b[1])^2 + (a[2] - b[2])^2) end

	local divSingle, len = vec2.divSingle, vec2.len
	function vec2.norm(a)         return divSingle(a, len(a)) end
	function vec2.setLen(a, b)    return divSingle(a, len(a) / b) end

	function vec2.right(a)        return {a[2], -a[1]} end
	function vec2.left(a)         return {-a[2], a[1]} end
	function vec2.neg(a)          return {-a[1], -a[2]} end

	local sin, cos = math.sin, math.cos
	function vec2.getRotMatrix(angle, dest)
		local s, c = sin(angle), cos(angle)
		dest[1], dest[2],
		dest[3], dest[4]
		=
		c, -s,
		s,  c
	end
	function vec2.mulMatrix(a, m)
		return {
			a[1]*m[1] + a[2]*m[2],
			a[1]*m[3] + a[2]*m[4],
		}
	end
	local getRotMatrix, mulMatrix = vec2.getRotMatrix, vec2.mulMatrix
	function vec2.rot(a, angle)
		local m = {}
		getRotMatrix(angle, m)
		return mulMatrix(a, m)
	end
end