做了一張640*1136的圖片，旋轉之後，fps從60降低到30.
If your sprites are large, and possibly rotated or scaled or with opacity < 255, and you're running this on an older device (1st or 2nd generation), then you may have simply run into the performance limitation of these devices.
You may be able to improve performance in particular if you use large sprites, or sprites that are rotated and scaled, by using CCSpriteBatchNode and a texture atlas to which you add each of the sprite's images. You can also reduce the color bit depth of the textures from 32-bit to 16-bit or even PVR compressed.
If you changed any of the default startup settings: for example changing the frame buffer from 16 bit to 32 bit or enabling depth buffering can also decrease performance.
Since you only have 6 sprites, wouldn't it be interesting to test what happens if you run your sample app with 5, 4, 3, 2, 1 and no sprites?
