86 lines
1.4 KiB
ArmAsm
86 lines
1.4 KiB
ArmAsm
;===========================================
|
|
; hgr draw sprite (only at 7-bit boundaries)
|
|
;===========================================
|
|
; SPRITE in INL/INH
|
|
; Location at SPRITE_X SPRITE_Y
|
|
|
|
; xsize, ysize in first two bytes
|
|
|
|
; sprite AT INL/INH
|
|
|
|
hgr_draw_sprite:
|
|
|
|
ldy #0
|
|
lda (INL),Y ; load xsize
|
|
clc
|
|
adc SPRITE_X
|
|
sta sprite_width_end_smc+1 ; self modify for end of line
|
|
|
|
iny ; load ysize
|
|
lda (INL),Y
|
|
sta sprite_ysize_smc+1 ; self modify
|
|
|
|
; point smc to sprite
|
|
lda INL ; 16-bit add
|
|
sta sprite_smc1+1
|
|
lda INH
|
|
sta sprite_smc1+2
|
|
|
|
|
|
ldx #0 ; X is pointer offset
|
|
stx CURRENT_ROW ; actual row
|
|
|
|
ldx #2
|
|
|
|
hgr_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
|
|
|
|
; eor #$00 draws on page2
|
|
; eor #$60 draws on page1
|
|
;hgr_sprite_page_smc:
|
|
; eor #$00
|
|
clc
|
|
adc DRAW_PAGE
|
|
sta GBASH
|
|
; eor #$60
|
|
; sta INH
|
|
|
|
ldy SPRITE_X
|
|
|
|
sprite_inner_loop:
|
|
|
|
|
|
sprite_smc1:
|
|
lda $f000,X ; load sprite data
|
|
sta (GBASL),Y ; store to screen
|
|
|
|
inx ; increment sprite offset
|
|
iny ; increment output position
|
|
|
|
|
|
sprite_width_end_smc:
|
|
cpy #6 ; see if reached end of row
|
|
bne sprite_inner_loop ; if not, loop
|
|
|
|
|
|
inc CURRENT_ROW ; row
|
|
lda CURRENT_ROW ; row
|
|
|
|
sprite_ysize_smc:
|
|
cmp #31 ; see if at end
|
|
bne hgr_sprite_yloop ; if not, loop
|
|
|
|
rts
|
|
|