Blitter Objects

Problem: Can I reverse an image for later use, without displaying it on screen?
Remedy: Yes. PASTE BOB works perfectly with flipped images, and can be used directly with HREV, VREV and REV. If you want to reverse an image quickly, without displaying a Bob, try something like this:

X> Paste Bob 500,500,Vrev(1)

Since the coordinates lie outside of the current screen area, the image is not displayed, but it is still flipped by the PASTE BOB command.

Problem: I want to flip my Sprites as well as my Bobs?
Remedy: The flip functions do not work with Sprites directly, but there is no problem in displaying a flipped Bob image as a Sprite. This line would be completely ignored:

X> Sprite 8,300,100,Hrev(5)

But the following routine will solve your problem:

E> Load "AMOSPro_Tutorial:Objects/Sprites.abk"
   Curs Off : Cls 0 : Flash Off : Get Sprite Palette
   Paste Bob 50,50,Vrev(5)
   Sprite 8,300,100,5
   Wait Vbl

Problem: Can I check for a collision between two copies of the same image, for example, between an original image and its own mirror-image?
Remedy: Yes, but it is not recommended. If the image's hot spot has been centred the results should be acceptable, but if the hot spot is asymmetrical you will generate unpredictable problems.