dos33fsprogs/asm_routines/hgr_putsprite.s

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;FIXME -- this doesn't actuall work yet
;=============================================
; hgr_put_sprite
;=============================================
; Sprite to display in INH,INL
; Location is XPOS,YPOS
hgr_put_sprite:
ldy #0 ; byte 0 is xsize ; 2
lda (INL),Y ; 5
sta CH ; xsize is in CH ; 3
iny ; 2
lda (INL),Y ; byte 1 is ysize ; 5
sta CV ; ysize is in CV ; 3
iny ; 2
lda YPOS ; make a copy of ypos ; 3
sta TEMPY ; as we modify it ; 3
;===========
; 28
hgr_put_sprite_loop:
sty TEMP ; save sprite pointer ; 3
lda TEMPY ; load tempy
lsr
lsr ; divide by 8 to get proper row
; but mul by 4 because array is 2byte addr
tay ; put in Y
lda TEMPY
and #$7 ; bottom 3 bits
asl
asl
sta SPRITETEMP
lda hgr_offsets,Y ; lookup hi-res row address ; 5
clc
adc XPOS ; add in XPOS (FIXME: which is div by 7)
sta OUTL ; store out low byte of addy ; 3
lda hgr_offsets+1,Y ; look up high byte ; 5
adc SPRITETEMP
adc DRAW_PAGE ; ; 3
sta OUTH ; and store it out ; 3
ldy TEMP ; restore sprite pointer ; 3
; OUTH:OUTL now points at right place
ldx CH ; load xsize into x ; 3
hgr_put_sprite_pixel:
lda (INL),Y ; get sprite colors ; 5
iny ; increment sprite pointer ; 2
sty TEMP ; save sprite pointer ; 3
ldy #$0 ; 2
sta (OUTL),Y
hgr_put_sprite_done_draw:
ldy TEMP ; restore sprite pointer ; 3
inc OUTL ; increment output pointer ; 5
dex ; decrement x counter ; 2
bne hgr_put_sprite_pixel ; if not done, keep looping ; 2nt/3
inc TEMPY ; 5
dec CV ; decemenet total y count ; 5
bne hgr_put_sprite_loop ; loop if not done ; 2nt/3
rts ; return ; 6