mirror of
https://github.com/deater/dos33fsprogs.git
synced 2024-06-06 01:29:27 +00:00
127 lines
1.6 KiB
ArmAsm
127 lines
1.6 KiB
ArmAsm
;===========================================
|
|
; hgr draw sprite (only at 7-bit boundaries)
|
|
;===========================================
|
|
; SPRITE in INL/INH
|
|
; Location at CURSOR_X CURSOR_Y
|
|
|
|
; xsize, ysize in first two bytes
|
|
|
|
; sprite AT INL/INH
|
|
|
|
hgr_draw_sprite:
|
|
|
|
; self modify to shift for odd start location
|
|
|
|
; SEC=$38 0b0011 1000 CLC=$18 0b0001 10000
|
|
|
|
lda CURSOR_X
|
|
lsr
|
|
bcc make_it_even
|
|
|
|
make_it_odd:
|
|
lda #$18
|
|
bne make_it_so
|
|
make_it_even:
|
|
lda #$38
|
|
make_it_so:
|
|
sta odd_even_smc
|
|
|
|
|
|
ldy #0
|
|
lda (INL),Y ; load xsize
|
|
clc
|
|
adc CURSOR_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
|
|
|
|
; skip the xsize/ysize and point to sprite
|
|
clc
|
|
lda INL ; 16-bit add
|
|
adc #2
|
|
sta sprite_smc1+1
|
|
lda INH
|
|
adc #0
|
|
sta sprite_smc1+2
|
|
|
|
ldx #0 ; X is pointer offset
|
|
|
|
stx MASK ; actual row
|
|
|
|
hgr_sprite_yloop:
|
|
|
|
lda MASK ; row
|
|
|
|
clc
|
|
adc CURSOR_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
|
|
sta GBASH
|
|
|
|
ldy CURSOR_X
|
|
|
|
sprite_inner_loop:
|
|
|
|
sprite_smc1:
|
|
lda $d000 ; get sprite pattern
|
|
|
|
; lsr
|
|
|
|
odd_even_smc:
|
|
sec
|
|
bcs no_adjust
|
|
|
|
asl
|
|
php
|
|
clc
|
|
lsr
|
|
plp
|
|
ror
|
|
no_adjust:
|
|
;? Xcababab
|
|
;X cababab?
|
|
;? X0cababa
|
|
|
|
; clc ; rol asl
|
|
; rol
|
|
|
|
|
|
|
|
sta (GBASL),Y ; store out
|
|
|
|
inx
|
|
iny
|
|
|
|
|
|
inc sprite_smc1+1
|
|
bne sprite_noflo
|
|
inc sprite_smc1+2
|
|
sprite_noflo:
|
|
|
|
sprite_width_end_smc:
|
|
cpy #6
|
|
bne sprite_inner_loop
|
|
|
|
|
|
inc MASK ; row
|
|
lda MASK ; row
|
|
|
|
sprite_ysize_smc:
|
|
cmp #31
|
|
bne hgr_sprite_yloop
|
|
|
|
rts
|
|
|