Corona SDK – Scrolling landscape

Here are a few ideas to get started creating a scrolling background. Create a background image that repeats, where the left edge would tile seamlessly when connected to the right edge. Copy a section the size of the visible area of the screen and add it to the right side of the image.

Here are a couple images for example. Look at the images carefully and you will see the the 480 pixels on the right side match the first 480 pixels on the left.

 

These images link to the originals at full size. You can download them to use with the example code which follows.

 

Here’s a simple example that works with a single image.

 

local landscape = display.newImageRect( "landscape-1.png", 1440, 320 )

-- landscape:setReferencePoint( display.TopLeftReferencePoint )
landscape_1.anchorX = 0
landscape_1.anchorY = 0
landscape_1.x = 0
landscape_1.y = 0

local function reset_landscape( landscape )
	landscape.x = 0
	transition.to( landscape, {x=0-1440+480, time=30000, onComplete=reset_landscape} )
end

reset_landscape( landscape_1 )

Here’s an example that takes the code above and turns it into a function allowing you to create more animated landscapes without having to duplicate the code.

local function make_landscape( image, width, height, time )
	local landscape = display.newImageRect( image, width, height )

	-- landscape:setReferencePoint( display.TopLeftReferencePoint )
	landscape.anchorX = 0
	landscape.anchorY = 0	
	landscape.x = 0
	landscape.y = 320 - height
	landscape.time = time
	
	local function reset_landscape( landscape )
		landscape.x = 0
		transition.to( landscape, {x=0-landscape.width+480, time=landscape.time, onComplete=reset_landscape} )
	end
	
	reset_landscape( landscape )
	
	return landscape
end 

local landscape_group = display.newGroup()

local landscape_1 = make_landscape( "Landscape-1.png", 1440, 86, 10000 )
local landscape_2 = make_landscape( "Landscape-2.png", 1440, 168, 20000 )
local landscape_3 = make_landscape( "Landscape-3.png", 1440, 215, 30000 )

landscape_group:insert( landscape_3 )
landscape_group:insert( landscape_2 )
landscape_group:insert( landscape_1 )