mirror of
https://github.com/deater/dos33fsprogs.git
synced 2025-01-09 10:30:21 +00:00
93 lines
1.5 KiB
ArmAsm
93 lines
1.5 KiB
ArmAsm
;================================================
|
|
; hgr draw sprite mask (only at 7-bit boundaries)
|
|
;================================================
|
|
; SPRITE in INL/INH
|
|
; MASK in MASKL/MASKH
|
|
|
|
; Location at SPRITE_X SPRITE_Y
|
|
|
|
; xsize, ysize in first two bytes
|
|
|
|
; sprite AT INL/INH
|
|
|
|
hgr_draw_sprite_mask:
|
|
|
|
ldy #0
|
|
lda (INL),Y ; load xsize
|
|
clc
|
|
adc SPRITE_X
|
|
sta hsm_sprite_width_end_smc+1 ; self modify for end of line
|
|
|
|
iny ; load ysize
|
|
lda (INL),Y
|
|
sta hsm_sprite_ysize_smc+1 ; self modify
|
|
|
|
; point smc to sprite
|
|
lda INL ; 16-bit add
|
|
sta hsm_sprite_smc1+1
|
|
lda INH
|
|
sta hsm_sprite_smc1+2
|
|
|
|
lda MASKL
|
|
sta hsm_mask_smc1+1
|
|
lda MASKH
|
|
sta hsm_mask_smc1+2
|
|
|
|
ldx #0 ; X is pointer offset
|
|
stx CURRENT_ROW ; actual row
|
|
|
|
ldx #2
|
|
|
|
hgr_sm_sprite_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_sm_sprite_inner_loop:
|
|
|
|
|
|
lda (GBASL),Y ; load bg
|
|
hsm_sprite_smc1:
|
|
eor $f000,X ; load sprite data
|
|
hsm_mask_smc1:
|
|
and $f000,X
|
|
eor (GBASL),Y
|
|
sta (GBASL),Y ; store to screen
|
|
|
|
inx ; increment sprite offset
|
|
iny ; increment output position
|
|
|
|
|
|
hsm_sprite_width_end_smc:
|
|
cpy #6 ; see if reached end of row
|
|
bne hgr_sm_sprite_inner_loop ; if not, loop
|
|
|
|
|
|
inc CURRENT_ROW ; row
|
|
lda CURRENT_ROW ; row
|
|
|
|
hsm_sprite_ysize_smc:
|
|
cmp #31 ; see if at end
|
|
bne hgr_sm_sprite_yloop ; if not, loop
|
|
|
|
rts
|
|
|
|
|
|
|