function _init()
	window{cursor=0} -- Hide the mouse cursor
	tch = touch.new() -- Initializing the touch structure
end

function _draw()
	-- Touch Structure Update. This is necessary to determine touch.
	tch:check() 

	--[[
	*** Wait until it truly becomes the initial state ***

	Since _init cannot fully initialize, it waits for time to pass in the main program.
	It seems that the time t() stops in _init, and the mouse position does not change. 
	It seems that time progresses entirely within _draw(_update).

	This is to prevent unnecessary tap events from occurring because a touch is 
	determined by moving the position of the mouse cursor, and the initial position of 
	the mouse cannot be obtained correctly.

	There may be a way to avoid this using memory manipulation, etc. 
	This decision statement is clearly a waste of processing.
	--]]
	if t() < 0.2 then return end

	-- Processes when it is determined that a touch has occurred.
	if tch.tap then
		splatter(tch.x, tch.y)
	end
end

--[[
It's not used within the program, but is useful 
for making the mouse cursor visible again.
--]]
function rst()
	cls()
	window { cursor=1 }
end

--[[
Creates an ink splatter effect.
This is just to make the examples a bit more interesting. Have fun!
--]]
function splatter(x, y)
	local col = flr(rnd(31)+1)
	local mdist = rnd(20)+10
	for i=0,mdist do
		local ang = rnd(1)
		local dist = rnd(mdist)
		local rad = rnd(mdist-dist)
		local xx = dist * cos(ang) + x
		local yy = dist * sin(ang) + y
		circfill(xx, yy, rad, col)
	end
end

--[[
Touch Structure
This determines if a tap has been performed by touch 
operation when the mouse cursor is moved.
--]]
touch = {}
touch.new = function()
	local x, y, _ = mouse()
	local obj = {}
	obj.x = 0
	obj.y = 0
	obj.tap = false
	obj.check = function(self)
		local x, y, _ = mouse()
		if self.tap == false and (x != self.x or y != self.y) then
			self.x = x
			self.y = y
			self.tap = true
		else
			self.tap = false
		end
	end
	return obj
end