Creating a texture altas in SpriteKit from an existing texture atlas jpg - animation

Question

I am trying to create a texture atlas using existing assets from a previous image asset that was created outside of Xcode/my machine.
Importing the image into Xcode does not "split" it, and I am unsure how to tell Xcode / SpriteKit where the "atlas" locations are.
Other than using an image editor and manually eating each image as an asset, how can I convince Xcode that the image is really an atlas already?
Finally, is it even worth it to use an atlas, as I have to cycle through the image myself to do animation; am I better off hardcoding (!) the x/y positions of the atlas strip and doing some sort of rotation / loop code in an SKAction?

Answer 1

Decided to split the old atlas into separate images, then load them with a .atlas folder. Also decided to load all file names and perform a .sort on an array, then go through that array and load the file names in the "correct" order.
function snippet below:
func AssignTextureAtlas(atlas: SKTextureAtlas)
{
var arrTextureNames: Array<String> = []
//Create texture atlas array
for (var i = 0; i < atlas.textureNames.count; i++)
{
var myText = atlas.textureNames[i] as String
arrTextureNames.append(myText)
}
arrTextureNames.sort( {$0 < $1})
for (var i = 0; i < arrTextureNames.count; i++)
{
var myTexture = atlas.textureNamed(arrTextureNames[i])
arr.insert(myTexture, atIndex: 0)
}
//...more code here, until:
self.runAction(SKAction.repeatActionForever(SKAction.animateWithTextures(arr, timePerFrame: 0.1, resize: false, restore: true)), withKey: "TEST")
}