gistfile1.txt

--pan
				local lastX = 0
				local lastY = 0
				local touchNum = 0
				local touch1 = false
				local touch2 = false
				local touch1X = 0
				local touch1Y = 0
				local touch2X = 0
				local touch2Y = 0
				local zoomStart = 0
				local distStart = 0
				local dragOkay = false
				function onObjectTouch( event )
					--zoom
					if touchNum > 1 and touchNum < 3 then
						gameGroup.xScale = math.max(1,math.min(10,zoomStart*(math.sqrt((touch2X-touch1X)*(touch2X-touch1X) + (touch2Y-touch1Y)*(touch2Y-touch1Y)))/distStart))
						gameGroup.yScale = gameGroup.xScale
					end
					if event.phase == "began" then
						lastX = event.x
						lastY = event.y
						--add touch
						touchNum = touchNum + 1
						--add touch id
						if touch1 == false then
							touch1 = event.id
							touch1X = event.x
							touch1Y = event.y
						elseif touch2 == false then
							touch2 = event.id
							touch2X = event.x
							touch2Y = event.y
							--remember start of zoom
							zoomStart = gameGroup.xScale
							distStart = math.sqrt((touch2X-touch1X)*(touch2X-touch1X) + (touch2Y-touch1Y)*(touch2Y-touch1Y))
						end
					elseif event.phase == "moved" then
						--this is the first touch
						if touch1 == event.id then
							touch1X = event.x
							touch1Y = event.y
						end
						--this is the second touch
						if touch2 == event.id then
							touch2X = event.x
							touch2Y = event.y
						end
						--zoom
						if touchNum > 1 and touchNum < 3 then
							dragOkay = false
							gameGroup.xScale = math.max(1,math.min(10,zoomStart*(math.sqrt((touch2X-touch1X)*(touch2X-touch1X) + (touch2Y-touch1Y)*(touch2Y-touch1Y)))/distStart))
							gameGroup.yScale = gameGroup.xScale
						elseif touchNum > 1 then
							dragOkay = false
						end
					else
						--remove touch
						touchNum = touchNum - 1
						--okay to drag
						if touchNum == 0 then
							dragOkay = true
						end
						--remove touch id
						if touch1 == event.id then
							touch1 = false
						elseif touch2 == event.id then
							touch2 = false
						end
					end
					if touchNum == 1 and dragOkay == true then
						gameGroup.x = math.min( gameGroup.width,math.max(-gameGroup.width, gameGroup.x + event.x - lastX))
						lastX = event.x
						gameGroup.y = math.min( gameGroup.height,math.max(-gameGroup.height,gameGroup.y + event.y - lastY))
						lastY = event.y
					end
					--fix bg
					background.x = gameGroup.x*(1-gameGroup.xScale)*.1 + screenCX
					background.y = gameGroup.y*(1-gameGroup.xScale)*.1 + screenCY
					background.xScale = gameGroup.xScale
					background.yScale = gameGroup.yScale
					return true
				end
				Runtime:addEventListener( "touch", onObjectTouch )