spine-runtimes/spine-lua/utils.lua

-------------------------------------------------------------------------------
-- Spine Runtimes Software License v2.5
--
-- Copyright (c) 2013-2016, Esoteric Software
-- All rights reserved.
--
-- You are granted a perpetual, non-exclusive, non-sublicensable, and
-- non-transferable license to use, install, execute, and perform the Spine
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-- the Spine Software License Agreement), you may not (a) modify, translate,
-- adapt, or develop new applications using the Spine Runtimes or otherwise
-- create derivative works or improvements of the Spine Runtimes or (b) remove,
-- delete, alter, or obscure any trademarks or any copyright, trademark, patent,
-- or other intellectual property or proprietary rights notices on or in the
-- Software, including any copy thereof. Redistributions in binary or source
-- form must include this license and terms.
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-- THIS SOFTWARE IS PROVIDED BY ESOTERIC SOFTWARE "AS IS" AND ANY EXPRESS OR
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-- EVENT SHALL ESOTERIC SOFTWARE BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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-------------------------------------------------------------------------------

local utils = {}

local math_sqrt = math.sqrt
local math_random = math.random

utils.degRad = math.pi / 180

function tablePrint (tt, indent, done)
	done = done or {}
	for key, value in pairs(tt) do
		local spaces = string.rep (" ", indent)
		if type(value) == "table" and not done [value] then
			done [value] = true
			print(spaces .. "{")
			utils.print(value, indent + 2, done)
			print(spaces .. "}")
		else
			io.write(spaces .. tostring(key) .. " = ")
			utils.print(value, indent + 2, done)
		end
	end
end

function utils.print (value, indent, done)
	indent = indent or 0
	if "nil" == type(value) then
		print(tostring(nil))
	elseif "table" == type(value) then
		local spaces = string.rep (" ", indent)
		print(spaces .. "{")
		tablePrint(value, indent + 2)
		print(spaces .. "}")
	elseif "string" == type(value) then
		print("\"" .. value .. "\"")
	else
		print(tostring(value))
	end
end

function utils.indexOf (haystack, needle)
	for i,value in ipairs(haystack) do
		if value == needle then return i end
	end
	return nil
end

function utils.copy (from, to)
	if not to then to = {} end
	for k,v in pairs(from) do
		to[k] = v
	end
	return to
end

function utils.newNumberArray (size)
	local a = {}
	local i = 1
	while i <= size do
		a[i] = 0
		i = i + 1
	end
	return a
end

function utils.newNumberArrayZero (size)
	local a = {}
	local i = 0
	while i < size do
		a[i] = 0
		i = i + 1
	end
	return a
end

function utils.setArraySize (array, size)
	if #array == size then return array end
	if #array < size then
		local i = #array + 1
		while i <= size do
			array[i] = 0
			i = i + 1
		end
	else
		local originalSize = #array
		local i = originalSize
		while i > size do
			array[i] = nil -- dirty trick to appease # without realloc
			i = i - 1
		end
	end
	return array
end

function utils.arrayCopy (src, srcOffset, dst, dstOffset, size)
	local n = srcOffset + size
	while srcOffset < n do
		dst[dstOffset] = src[srcOffset]
		dstOffset = dstOffset + 1
		srcOffset = srcOffset + 1
	end
end

function utils.clamp (value, min, max)
	if value < min then return min end
	if value > max then return max end
	return value
end

function utils.signum (value)
  if value < 0 then
    return -1
  elseif value > 0 then
    return 1
  else
    return 0
  end
end

-- Implements Java float modulo
function utils.mod(a, b)
  if b < 0 then b = -b end
  if a < 0 then
    return -(-a % b)
  else
    return a % b
  end
end

function utils.randomTriangular(min, max)
	return utils.randomTriangularWith(min, max, (min + max) * 0.5)
end

function utils.randomTriangularWith(min, max, mode)
	local u = math.random()
	local d = max - min
	if (u <= (mode - min) / d) then return min + math_sqrt(u * d * (mode - min)) end
	return max - math_sqrt((1 - u) * d * (max - mode))
end

return utils