Is there a reason that the framerate in a cocos2d project drops from 60 fps to 30 fps as soon as I add a background image? This is consistent. The scene's not very complicated either - it's just a menu scene and has 3-4 buttons. With a gradient background, the scene runs at 60 fps. But as soon as I replace the gradient background with an image, the framerate drops down to 30 fps.
I thought the issue might be with a fullscreen image and so chopped the image into two smaller parts and used that with a gradient background. If I add the smaller of the two images, then the framerate remains at 60fps. But once I add the bigger image (which is about half the screen size) the framerate again drops to 30 fps.
It's worse on actual game scenes - with a background image and on iPad retina, I get around 5-6 fps.
Is this a known issue with V3? I don't believe I saw such degradation in performance with V2. But I haven't actually tried the current code with V2 to verify this.