Re: A86: Question on tile maps


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Re: A86: Question on tile maps




i assume all this triple buffering stuff is going into ATOM.  that'll be
really cool when it's finished.



In a message dated 1/27/99 14:34:50 Eastern Standard Time, david@acz.org
writes:

> I've found that instead of using a SLOW sprite routine that saves the
>  background, it's almost always much faster and easier to just save the
>  background each frame into a secondary buffer.  I call it "tripple
>  buffering".  You have your Video Ram or Video Buffer, Virtual Screen or
>  Double Buffer, and you have the Map Screen or Map Buffer.
>  
>  You draw the map to the Map Buffer.  At the beginning of each frame (top of
>  the main loop), copy the Map Buffer to the Virtual Screen.  This will
>  effectively erase any sprites that were drawn the previous frame.  During
>  the frame, use whatever putsprite routine that you want and draw your
>  sprites to the Virtual Screen.  Don't worry about where they were or what
>  was behind, them, just draw them as fast as possible.  At the end of the
>  frame, copy the Virtual Screen to Video Ram.  This will save you alot of
>  effort when programming, and it will be much faster if you have more than
>  two or three on screen sprites.  An extra 21000 t's for a buffer copy isn't
>  much at all.
>