dos33fsprogs/games/sb/fish/hgr_sprite.s
Vince Weaver 524717f987 fish: hook up score code
was more of a pain than you'd think.  have to be careful reusing
sprite code
2024-06-11 16:21:49 -04:00

80 lines
1.3 KiB
ArmAsm

;================================================
; hgr draw sprite (only at 7-bit boundaries)
;================================================
; just plain draw the sprite
; no masking or transparency
; draws to page DRAWPAGE
; SPRITE in INL/INH
; Location at SPRITE_X SPRITE_Y
; xsize, ysize in first two bytes
hgr_draw_sprite:
ldy #0
lda (INL),Y ; load xsize
clc
adc SPRITE_X
sta hds_sprite_width_end_smc+1 ; self modify for end of line
iny ; load ysize
lda (INL),Y
sta hds_sprite_ysize_smc+1 ; self modify
; point smc to sprite
lda INL ; 16-bit add
sta hds_sprite_smc1+1
lda INH
sta hds_sprite_smc1+2
ldx #0 ; X is pointer offset
stx CURRENT_ROW ; actual row
ldx #2
hgr_ds_yloop:
lda CURRENT_ROW ; row
clc
adc SPRITE_Y ; add in cursor_y
; calc GBASL/GBASH
tay ; get output ROW into GBASL/H
lda hposn_low,Y
sta GBASL
lda hposn_high,Y
clc
adc DRAW_PAGE
sta GBASH
ldy SPRITE_X
hgr_ds_inner_loop:
hds_sprite_smc1:
lda $f000,X ; load sprite data
sta (GBASL),Y ; store to screen
inx ; increment sprite offset
iny ; increment output position
hds_sprite_width_end_smc:
cpy #6 ; see if reached end of row
bne hgr_ds_inner_loop ; if not, loop
inc CURRENT_ROW ; row
lda CURRENT_ROW ; row
hds_sprite_ysize_smc:
cmp #31 ; see if at end
bne hgr_ds_yloop ; if not, loop
rts