Ten to hundred lines of code to make a very small paint game for kids

main.lua

currColor = "white"

local function save(  )
	display.save( allGroup, "group.jpg" )
end
local function loadVars(theSize)
	math.randomseed( os.time( ) )
	allGroup = display.newGroup()
	rectangles = {}
	currW = theSize
	currX = -currW
	currY = currW/2
	noOFRects = ((display.contentWidth/currW) * (display.contentHeight/currW)) + (display.contentWidth*3/currW)
	R = 0
	G = 0
	B = 0
end
local function paintMe(event)
	while R == 0 or R == 1 do
		R = math.random( )
	end
	while G == 0 or G == 1 do
		G = math.random( )
	end
	while B == 0 or B == 1 do
		B = math.random( )
	end
	event.target:setFillColor( R,G,B )

	R = 0
	G = 0
	B = 0
end
local function loadrectangles()
	for i=1,noOFRects do
		currX = currX + currW
		if currX >= display.contentWidth + currW then
			currX = -currW
			currY = currY + currW
		end
		rectangles[i] = display.newRect( currX, currY, currW,currW )
		if currColor == "white" then
			rectangles[i]:setFillColor( 1,1,1 )
		else
			rectangles[i]:setFillColor( 0,0,0 )
		end

		allGroup:insert( rectangles[i] )
		rectangles[i]:addEventListener("touch",paintMe)
	end

	resetR1:toFront( )
	resetR2:toFront( )
	resetR3:toFront( )
	resetR4:toFront( )
	resetR5:toFront( )
end
local function clearMe()
	currColor = "black"
	resetR1:setFillColor( 0,0,0 )
	for i=1,noOFRects do
		rectangles[i]:setFillColor( 0,0,0 )
	end
end
local function clearMe2()
	currColor = "white"
	for i=1,noOFRects do
		rectangles[i]:setFillColor( 1,1,1 )
	end
end

local function removeAll()
	for i=1,noOFRects do
		display.remove(rectangles[i])
		rectangles[i] = nil
	end
end
local function small()
	removeAll()
	loadVars (5)
	loadrectangles()
end
local function medium()
	removeAll()
	loadVars (10)
	loadrectangles()
end
local function large()
	removeAll()
	loadVars (15)
	loadrectangles()
end

loadVars (10)

resetR1 = display.newRoundedRect( 30, 50, 50, 50, 12 )
resetR1:setFillColor( 0,0,0 )
resetR1:setStrokeColor ( 0,0,1 )
resetR1.strokeWidth = 1
resetR1:addEventListener( "tap", clearMe )

resetR2 = display.newRoundedRect( display.contentWidth - 30, 50, 50, 50, 12 )
resetR2:setFillColor( 1,1,1 )
resetR2:setStrokeColor ( 0,0,1 )
resetR2.strokeWidth = 1
resetR2:addEventListener( "tap", clearMe2 )

resetR3 = display.newRoundedRect( 30, display.contentHeight - 150, 30, 30, 12 )
resetR3:setFillColor( 0,1,0 )
resetR3:setStrokeColor ( 0,1,0 )
resetR3.strokeWidth = 1
resetR3:addEventListener( "tap", small )

resetR4 = display.newRoundedRect( 30, display.contentHeight - 110, 40, 40, 12 )
resetR4:setFillColor( 0,1,0 )
resetR4:setStrokeColor ( 0,1,0 )
resetR4.strokeWidth = 1
resetR4:addEventListener( "tap", medium )

resetR5 = display.newRoundedRect( 30, display.contentHeight - 60, 50, 50, 12 )
resetR5:setFillColor( 0,1,0 )
resetR5:setStrokeColor ( 0,1,0 )
resetR5.strokeWidth = 1
resetR5:addEventListener( "tap", large )

loadrectangles()