[A83] Re: Sprites

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[A83] Re: Sprites


Here is some code that moves a happy face around the screen:

        .nolist

        #include "ion.inc"      ;tells TASM--the compiler--what file to read 
from to define rom call memory addresses and such
        .list
GDown = 01h     ;key equates
GLeft = 02h
GRight = 03h
GUp = 04h
GClear = 0Fh

xpos = saferam3     ;user defined variables for 
ypos = xpos+1       ;x and y coordinates
#ifdef TI83P            ;a check for TASM to see whether it is making an 83 
program--if so, do the next two commands
    .org    progstart-2
    .db     $BB,$6D
#else               ;if it isn't an 83 program, then do something 
[#]else--the next line
        .org    progstart
#endif              ;simply ends the #ifdef command
    ret             

    jr      nc,lblStart ;Jumps to the beginning of the program (this line and 
the below three will be 
    .db     "Cole's Sprite Routine",0       ;The title displayed by 
ION--anything you want              ;defines where label begin is, program 
code follows this label
lblStart:
         ;Position sprite at 16,16
    ld hl,$1010
    ld (xpos),hl
Loop:
    call DrawSprites        ;calls lable drawsprites
    call Ionfastcopy        ;copys buffer to screen
    bcall(_cleargbuf)       ;clears graphbuffer
    call WaitKey            ;calls label waitkey
    cp gClear               ;if it was clear, return to ion
    ret z
    cp gLeft                ;if it was left
    jr z,Left               ;go to left
    cp gRight               ;etc...
    jr z,Right
    cp gUp
    jr z,Up
    cp gDown
    jr z,Down
    jr Loop
Left:
    ld a,(xpos)         ;loads the xpos into a and 
    sub 4                   ;subtracts 4
    jr c,Loop               ;makes sure sprite is still on screen
    ld (xpos),a         ;loads a back into xops
    jr Loop             ;jumps to the loop
Right:                      ;same as left but adds
    ld a,(xpos)
    add a,4
    cp 96-8
    jr nc,Loop
    ld (xpos),a
    jp Loop
Up:
    ld a,(ypos)
    sub 4
    jp c,Loop
    ld (ypos),a
    jp loop
Down:
    ld a,(ypos)
    add a,4
    cp 64-8
    jp nc,Loop
    ld (ypos),a
    jp loop
DrawSprites:
    ld a,(xpos)         ; a = xpos
    ld b,8                  ;b = sprite height
    ld hl,(ypos)            ;l = ypos
    ld ix,smiley            ; ix = sprite
    jp ionputsprite     ;jumps to ionputsprite which
                            ;copys screen to buffer and returns
WaitKey:                    ;waits for keypress
    ei
WaitKeyLoop:
    halt
    bcall(_getcsc)
    or a
    jr z,WaitKeyLoop
    ret


smiley:                 ;smileyface sprite
  .db %00111100
  .db %01000010
  .db %10100101
  .db %10000001
  .db %10100101
  .db %10011001
  .db %01000010
  .db %00111100

.end
END