Re: TIB: Help with Sprites(The ORIGINAL QUESTION!)

To: ti-basic@lists.ticalc.org
Subject: Re: TIB: Help with Sprites(The ORIGINAL QUESTION!)
From: ETTamme1@aol.com
Date: Sun, 30 Jan 2000 22:45:01 EST
Reply-To: ti-basic@lists.ticalc.org


    Hey guys, just a comment.  I think that if the subject of the letter 
changes you should change the subject heading with it.  If you keep it the 
same then  no one knows whether its the original topic or some other one.  

    About creating sprites on the 83 and 86, you cant really create an 
"actuall" sprite where it reads from a picture file and displays the sprite. 
You can make "psuedo sprites" though.  You can either (A) make a "header 
file" with your sprite image using pxl on and pxl off in the file, however 
this would take a TON of time to write.  or you could go option (B) and use 
characters from the 8X keyboard and the output( command to create your sprite 
in a similar type "header file".
    Then to draw your sprite you would simply set the x and y then call the 
program that your sprite is in and it will output the sprite according to the 
coordinates passed to it.
    sprites really are pretty complex. sprite engines usually copy the imige 
of where the sprite is about to be placed then it puts the sprite over it. 
Then when the sprite moves it blits the old image back over the sprite the 
stores the new place where the sprite will be placed then places the sprite 
over it.  In theory you could do this on a calc if you had the whole screen 
stored as a matrix or somthing so you could save and reproduce portions.  Not 
that you could do it with ANY speed or efficiency , but you can do it.  Youd 
be better off using Clrhome or Clcd  and then just re-rendering the whole 
screen.  Well anyway theres my thoughts on the subject. Hope it helps.
    Thanks,
        ~Eric