A86: re: moving sprites

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A86: re: moving sprites

This is probably an easy thing to do, but I am totally lost. I am trying to
display an 8x8 sprite on the screen and move it from one side to about
halfway across and back again. I tried using the PutSprite routine used in
Duckhunt, but instead of moving it across, it placed the sprites at
semi-random places. here's the routine if anyone wants to help.


;------------------
;This Routine was converted by AVD from Movax's 83
;Special thanks to ScaBBy for making it XOR Routine!
;------------------

;hl = image
;a = x coord
;e = y coord

PutSprite:
       push    hl              ; Save sprite address

;  Calculate the address in graphbuf 

        ld      hl,0            ; Do y*12
        ld      d,0
	ex	de,hl
	add	hl,hl
	add	hl,hl
	add	hl,hl
	add	hl,hl

        ld      d,0             ; Do x/8
        ld      e,a
        srl     e
        srl     e
        srl     e
        add     hl,de

        ld      de,$FC00
        add     hl,de           ; Add address to graphbuf

        ld      b,00000111b     ; Get the remainder of x/8
        and     b
        cp	0               ; Is this sprite aligned to 8*n,y?
        jp      z,ALIGN


;  Non aligned sprite blit starts here   

        pop     ix              ; ix->sprite
        ld      d,a             ; d=how many bits to shift each line

        ld      e,8             ; Line loop
LILOP:  ld      b,(ix+0)        ; Get sprite data

        ld      c,0             ; Shift loop
        push    de
SHLOP:  srl     b
        rr      c
        dec     d
        jp      nz,SHLOP
        pop     de

        ld      a,b             ; Write line to graphbuf
        xor     (hl)
        ld      (hl),a
        inc     hl
        ld      a,c
        xor     (hl)
        ld      (hl),a

        ld      bc,15           ; Calculate next line address
        add     hl,bc
        inc     ix              ; Inc spritepointer

        dec     e
        jp      nz,LILOP        ; Next line

        jp      DONE1


;   Aligned sprite blit starts here

ALIGN:                          ; Blit an aligned sprite to graphbuf
        pop     de              ; de->sprite
        ld      b,8
ALOP1:  ld      a,(de)
        xor      (hl)            ; xor=erase/blit
        ld      (hl),a
        inc     de
        push    bc
        ld      bc,16
        add     hl,bc
        pop     bc
        djnz    ALOP1

DONE1:
        ret



thanks for any help,

Jeff Zimmerman
gramdon@mail2.theonramp.net
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