epervier-old/gamecore/utils/math.lua

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-- loveutils.math : easy to use functions for mathematics and geometry.
--[[
Copyright © 2019 Kazhnuz
Permission is hereby granted, free of charge, to any person obtaining a copy of
this software and associated documentation files (the "Software"), to deal in
the Software without restriction, including without limitation the rights to
use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
the Software, and to permit persons to whom the Software is furnished to do so,
subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
]]
local Math = {}
-- ALGEBRA FUNCTIONS
-- Simple yet usefull functions not supported by base love2D
function Math.sign(x)
if (x < 0) then
return -1
elseif (x > 0) then
return 1
else
return 0
end
end
function Math.round(num)
return math.floor(num + 0.5)
end
function Math.toZero(num, sub)
local sub = math.floor(sub)
if math.abs(num) < sub then
return 0
else
return num - (sub * Math.sign(num))
end
end
-- VECTOR/DIRECTION functions
-- Easy-to-use function to handle point and motion
function Math.vector(x1, y1, x2, y2)
local vecx, vecy
vecx = x2 - x1
vexy = y2 - y1
return vecx, vecy
end
function Math.getMiddlePoint(x1, y1, x2, y2)
local newx, newy, vecx, vecy
vecx = math.max(x1, x2) - math.min(x1, x2)
vecy = math.max(y1, y2) - math.min(y1, y2)
newx = math.min(x1, x2) + (vecx / 2)
newy = math.min(y1, y2) + (vecy / 2)
return newx, newy
end
function Math.pointDistance(x1, y1, x2, y2)
local vecx, vecy
vecx = math.max(x1, x2) - math.min(x1, x2)
2019-04-01 08:09:36 +02:00
vecy = math.max(y1, y2) - math.min(y1, y2)
return math.sqrt(vecx^2 + vecy^2)
end
function Math.pointDirection(x1,y1,x2,y2)
local vecx, vecy, angle
vecy = y2 - y1
vecx = x2 - x1
angle = math.atan2(vecy, vecx)
return angle
end
-- STRING FUNCTIONS
-- Transform into string numbers
function Math.numberToString(x, length)
local length = length or 1
local string = ""
local x = x
if (x >= math.pow(10, length)) then
x = unitsNumber*10 - 1
string = string .. x
else
for i=1, (length-1) do
if (x < math.pow(10, length-i)) then
string = string .. "0"
end
end
string = string .. x
end
return string
end
-- COORDINATE FUNCTIONS
-- Easy computation on coordinate
function Math.floorCoord(x, y)
return math.floor(x), math.floor(y)
end
function Math.pixeliseCoord(x, y, factor)
x, y = Math.floorCoord(x / factor, y / factor)
x = x * factor
y = y * factor
return x, y
end
return Math