Re: A89: Programming Problem


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Re: A89: Programming Problem




Okay, I've just tried it again, putting 00 behind each index, but the 
same problem occurs: there's this really ugly line growing out of the 
ball as it moves around the screen. Just as a test, I shrank the 
program to just display the ball and then quit:

>>>  >>  ----------------------------CODE--------------------------
>>>  >>  #define SAVE_SCREEN
>>>  >>
>>>  >>  #include <nostub.h>
>>>  >>  #include <graph.h>
>>>  >>  #include <system.h>
>>>  >>  #include <sprites.h>
>>>  >>
>>>  >>  int _ti89;
>>>  >>
>>>  >>  int _main()
>>>  >>  {
>>>  >>          static unsigned int ball [] = {0x3c, 0x7e, 0xff, 0xff, 0xff,
>>>  >>  0xff, 0x7e, 0x3c};
>>>  >>          int key, x = 50, y = 50;
>>>  >>          void *kbq = kbd_queue ();
>>>  >>
>>>  >>          ClrScr ();

  >>              Sprite16(x, y, 8, ball, LCD_MEM, SPRT_XOR);

		while (OSdequeue (&key, kbq)) ;
>>>
>>>  >>
>>>  >>          return 0;
>>>  >>  }


even just doing this, the ball displays with a funny 3 pixel line 
sticking out of the left side of it... I don't know what's causing 
it, cause I sure as hell didn't put it there (at least I don't THINK 
I am :)

thanks for all you help,

Nathaniel Gibson
ngibson@ptd.net




>I've tried that but then the sprite looks really ugly, nothing like 
>what was intended. I think it's because Sprite16 expects and 
>unsigned int, but to do it that way, I need to redefine the array as 
>an unsigned long int. Any thoughts?
>
>Nathaniel Gibson
>ngibson@ptd.net
>
>>ok. to bad. There really should be a sprite8 routine.
>>But thats your problem anyway.
>>put your sprite-data in the left part of the sprite instead (just 
>>add 00 at the
>>end of every number, 0x3c becomes 0x3c00 and so on)
>>and let it go from 0 to 151.  that should work. but it's an ugly sollution :)
>>
>>//Olle
>>
>>Nathaniel Gibson wrote:
>>>
>>>  No, there isn't a Sprite8 routine, and I'm not well-versed enough to
>>>  write one myself. I understand that I'm moving a sprite that is
>>>  actually 16x8, that's why the check in the x direction is at 0 and
>>>  143, and not 0 and 151. The problem is Sprite16 doesn't accept a
>>>  negative number for the location of the sprite, otherwise I would use
>>>  -8 and 143.
>>>
>>>  >Same problem as someone else here had before.
>>>  >you define a 16x8 sprite, but only write sprite data in the 
>>>right half of it.
>>>  >the left half of the sprite is all blank.
>>>  >(thats why it is called sprite16, it handles 16pixel wide sprites)
>>>  >Your program thinks it moves around a 16x8 sprite.
>>>  >Isn't there a sprite8 or something like that, to use?
>>>  >then you should use that when moving 8x8 sprites, and define 
>>>your sprite data
>>>  >array as char instead of int.
>>>  >
>>>  >//Olle
>>>  >
>>>  >Nathaniel Gibson wrote:
>>>  >>
>>>  >>  I wrote the program below just to see if I could get a ball to bounce
>>>  >>  around the screen. Everything works except for when the ball hits the
>>>  >>  left side of the screen: it looks like it hits 8 pixels too soon. Can
>>>  >>  someone please tell me what I'm doing wrong? I think it has something
>>>  >>  to do with the way Sprite16 processes the sprite, but I'm not sure.
>>>  >>
>>>  >>  Thanks in advance,
>>>  >>
>>>  >>  Nathaniel Gibson
>>>  >>  ngibson@ptd.net
>>>  >>
>>>  >>  ----------------------------CODE--------------------------
>>>  >>  #define SAVE_SCREEN
>>>  >>
>>>  >>  #include <nostub.h>
>>>  >>  #include <graph.h>
>>>  >>  #include <system.h>
>>>  >>  #include <sprites.h>
>>>  >>
>>>  >>  int _ti89;
>>>  >>
>>>  >>  int _main()
>>>  >>  {
>>>  >>          static unsigned int ball [] = {0x3c, 0x7e, 0xff, 0xff, 0xff,
>>>  >>  0xff, 0x7e, 0x3c};
>>>  >>          int key, x = 50, y = 50, xChange = 1, yChange = 1;
>>>  >>          void *kbq = kbd_queue ();
>>>  >>          long int j;
>>>  >>
>>>  >>          ClrScr ();
>>>  >>
>>>  >>          while (OSdequeue (&key, kbq))   {
>>>  >>
>>>  >>                  if ((x == 0) || (x == 143))     xChange *= -1;
>>>  >>                  if ((y == 0) || (y == 91))      yChange *= -1;
>>>  >>
>>>  >>                  x += xChange;
>>>  >>                  y += yChange;
>>>  >>
>>>  >>                  Sprite16(x, y, 8, ball, LCD_MEM, SPRT_XOR);
>>>  >>                  for ( j = 0; j <= 50000; j++) ;
>>>  >>                  Sprite16(x, y, 8, ball, LCD_MEM, SPRT_XOR);
>>>  >>          }
>>>  >>
>>>  >>          return 0;
>>>  >>  }




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