I’d like to have some kind of backgound in my game, but want it to be scrollable (parallax effect). I’d like to do this by creating an image with the dimensions: displayWidth+tileWith x displayHeight+tileHeight and then offset this image with values from 0 to tileWidth and 0 to tileHeight to give an impression of an endless scroll in two directions.
But how do I compose such a large image from many smaller ones?
Just to answer myself…
I would up just making an array of individual tiles calling newImage with the same image. They were all places in the same group and scrolled together by adjusting the x/y values of the group:
local plxGroup = display.newGroup(); plxBgArr = {} local horizBgTileNum = math.ceil(displayWidth/tilePixSize+1) local verticBgTileNum = math.ceil(displayHeight/tilePixSize+1) local plxBgCnt = 1 for y = 0, verticBgTileNum-1 do for x = 0, horizBgTileNum-1 do LevelElements.plxBgArr[plxBgCnt] = display.newImage(plxGroup, "tileImage.png") LevelElements.plxBgArr[plxBgCnt].x = tilePixSize\*x + tilePixSize/2 LevelElements.plxBgArr[plxBgCnt].y = tilePixSize\*y + tilePixSize/2 plxBgCnt = plxBgCnt + 1 end end
Maybe this is even better (using less texture memory?) than a composite image for all I know…
At least it works 
Just to answer myself…
I would up just making an array of individual tiles calling newImage with the same image. They were all places in the same group and scrolled together by adjusting the x/y values of the group:
local plxGroup = display.newGroup(); plxBgArr = {} local horizBgTileNum = math.ceil(displayWidth/tilePixSize+1) local verticBgTileNum = math.ceil(displayHeight/tilePixSize+1) local plxBgCnt = 1 for y = 0, verticBgTileNum-1 do for x = 0, horizBgTileNum-1 do LevelElements.plxBgArr[plxBgCnt] = display.newImage(plxGroup, "tileImage.png") LevelElements.plxBgArr[plxBgCnt].x = tilePixSize\*x + tilePixSize/2 LevelElements.plxBgArr[plxBgCnt].y = tilePixSize\*y + tilePixSize/2 plxBgCnt = plxBgCnt + 1 end end
Maybe this is even better (using less texture memory?) than a composite image for all I know…
At least it works