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Re: DRAW & XDRAW... How to use
jh82 (webmasterNOweSPAM@jh82.i-p.com.invalid) wrote:
: I am in the process of making a huge, graphic fantasy game. The
: problem I have is that I lost my notes as to how to set up the DRAW &
: XDRAW commands. I do remember that it involves a ton of POKEs, but I
: can't remember the address to start at, or the byte codes. I seem to
: remember it being explained in a manual. If ANYONE can help me, please
: do. This is going to be a great game, but I can't finish it until I
: can get those instructions.
You're wanting to use shape tables.
You begin by defining a shape somewhere in memory...where is not
important, but the shape is defined as a byte stream something like this--
Byte: 1 - Number of shapes in table
2-3 - Offset (bytes) to 1st shape
4-5 - Offset (bytes) to 2nd shape
...
m-n - First shape
Shapes are defined as sequences of bytes, using 3-bit plotting/moving
commands. So each byte can hold as many as three instructions. The last
byte of the shape is zero. The codes are as follows:
No Plot, Move Up : 000
No Plot, Move Right: 001
No Plot, Move Down : 010
No Plot, Move Left : 011
Plot, Move Up : 100
Plot, move Right: 101
Plot, Move Down : 110
Plot, Move Left : 111
Once your shape table is defined, you must tell Applesoft where it is
located by putting the address into the pointer at location $E8-E9 (232-233).
To use it:
SCALE=s (Size of shape meaning distance per plot 0-255...0 means 256)
ROT=r (rotation, 0-255, but it's more or less in radians if I remember right
HCOLOR=c (0-7)
DRAW p AT x,y (plots shape #p starting at location x,y scaled to s and
rotated r in color c)
XDRAW p AT x,y (plots shape as DRAW does, but instead of plotting in color
c, it reverses the pixels where plotting happens)
: Also, I remember a sound routine I found in a game called Lemonade
: Stand, or something like that. If you have that program, I really need
: the sound routine from it. It's toward the end of the program, and
: involvers a lot of POKEs. If you have this, let me know.
Er, I have that around here someplace...
--Dave Althoff, ][.
Paying a rare visit to c.s.a2 after catching up on rec.roller-coaster.
Hi, folks, nice to be back again, if only briefly!
--
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