mathObjects.lua

local ret = {}

ret.makeMathObject = function (self, initialvalue, updateSpeed)
    local thing = {}
    thing.currentValue = initialvalue or 0
    thing.nextValue = initialvalue or 0
    thing.updateSpeed = updateSpeed = 20
    thing.set = function(self, newValue)
        self.nextValue = newValue
    end
    thing.update = function(self, dt)
        --dt is in seconds passed
        --at 60 fps it would be 0.01667
        local t = dt * self.updateSpeed
        --(1-t * a)+(t * b)
        self.currentValue = ( (1-t)*self.currentValue ) + ( t*self.nextValue )
    end

    if not self.mathObjectMT then
        self.mathObjectMT = {} --is this something you can do? idk
        self.mathObjectMT.__utilGetNumber = function (value) --return number from value of unknown type
            if type(value) == "table" then
                if value.currentValue then --if it has a currentValue
                    return value.currentValue
                else --if there were to be another special number type to check for, that goes here
                    return nil
                end
            elseif type(value) == number then
                return value
            else --some other random type like a string
                return nil
            end
        end
        self.mathObjectMT.__add = function(a,b) -- a+b
            local getNum;
            if type(a) == "table" and a.currentValue then
                getNum = getmetatable(a).__utilGetNumber
            else
                getNum = getmetatable(b).__utilGetNumber
            end
            return getNum(a) + getNum(b)
        end
        self.mathObjectMT.__sub = function(a,b) -- a-b
            local getNum;
            if type(a) == "table" and a.currentValue then
                getNum = getmetatable(a).__utilGetNumber
            else
                getNum = getmetatable(b).__utilGetNumber
            end
            return getNum(a) - getNum(b)
        end
        self.mathObjectMT.__mul = function(a,b) -- a*b
            local getNum;
            if type(a) == "table" and a.currentValue then
                getNum = getmetatable(a).__utilGetNumber
            else
                getNum = getmetatable(b).__utilGetNumber
            end
            return getNum(a) * getNum(b)
        end
        self.mathObjectMT.__div = function(a,b) -- a/b
            local getNum;
            if type(a) == "table" and a.currentValue then
                getNum = getmetatable(a).__utilGetNumber
            else
                getNum = getmetatable(b).__utilGetNumber
            end
            return getNum(a) / getNum(b)
        end
        self.mathObjectMT.__pow = function(a,b) -- a^b
            local getNum;
            if type(a) == "table" and a.currentValue then
                getNum = getmetatable(a).__utilGetNumber
            else
                getNum = getmetatable(b).__utilGetNumber
            end
            return getNum(a) ^ getNum(b)
        end
        self.mathObjectMT.__unm = function(a) -- -a
            return -(getmetatable(a).__utilGetNumber(a))
        end
    end
    setmetatable(thing, self.mathObjectMT)
    return thing
end

return ret