mirror of
https://github.com/deater/dos33fsprogs.git
synced 2024-06-26 00:29:29 +00:00
102 lines
1.2 KiB
ArmAsm
102 lines
1.2 KiB
ArmAsm
|
;========================
|
||
|
|
; draw letter
|
||
|
|
;========================
|
||
|
|
; so inefficient
|
||
|
|
; letter to draw in INL:INH
|
||
|
|
|
||
|
|
draw_letter:
|
||
|
|
|
||
|
|
ldy #$FF ; iterator
|
||
|
|
letter_loop:
|
||
|
|
|
||
|
|
|
||
|
|
hplot:
|
||
|
|
; setup X value
|
||
|
|
|
||
|
|
iny
|
||
|
|
|
||
|
|
jsr get_x ; get adjusted x-coord in A
|
||
|
|
|
||
|
|
tax ; put in X
|
||
|
|
|
||
|
|
; setup Y value
|
||
|
|
|
||
|
|
jsr get_y
|
||
|
|
|
||
|
|
ldy #0 ; set top of X value (FIXME)
|
||
|
|
|
||
|
|
jsr HPLOT0 ; plot at (Y,X), (A)
|
||
|
|
|
||
|
|
ldy SAVE_Y ; restore pointer
|
||
|
|
|
||
|
|
iny
|
||
|
|
|
||
|
|
hplot_to:
|
||
|
|
|
||
|
|
; get X value
|
||
|
|
|
||
|
|
jsr get_x ; get adjusted x-coord in A
|
||
|
|
|
||
|
|
pha ; save for later
|
||
|
|
|
||
|
|
lda #0 ; wrap if > 256
|
||
|
|
adc #0
|
||
|
|
tax
|
||
|
|
|
||
|
|
; get Y value
|
||
|
|
|
||
|
|
jsr get_y
|
||
|
|
|
||
|
|
tay ; put into Y
|
||
|
|
|
||
|
|
pla ; restore X value
|
||
|
|
|
||
|
|
jsr HGLIN ; line to (X,A),(Y)
|
||
|
|
|
||
|
|
ldy SAVE_Y
|
||
|
|
|
||
|
|
iny
|
||
|
|
|
||
|
|
; see if at end of line or of whole thing
|
||
|
|
|
||
|
|
lda (INL),Y ; get next value
|
||
|
|
|
||
|
|
bmi letter_done ; if negative, we are done
|
||
|
|
|
||
|
|
cmp #$7F
|
||
|
|
beq hplot
|
||
|
|
bne hplot_to
|
||
|
|
|
||
|
|
letter_done:
|
||
|
|
rts
|
||
|
|
|
||
|
|
|
||
|
|
;================
|
||
|
|
; get next X co-ord
|
||
|
|
; multipy by 2
|
||
|
|
; increment y
|
||
|
|
get_x:
|
||
|
|
lda (INL),Y ; get X value
|
||
|
|
asl ; need to multiply by 2
|
||
|
|
clc
|
||
|
|
adc LETTER_X
|
||
|
|
|
||
|
|
iny
|
||
|
|
|
||
|
|
rts
|
||
|
|
|
||
|
|
;================
|
||
|
|
; get next Y co-ord
|
||
|
|
; increment y
|
||
|
|
; save to SAVE_Y
|
||
|
|
|
||
|
|
get_y:
|
||
|
|
sty SAVE_Y ; save Y value on stack for later
|
||
|
|
|
||
|
|
lda (INL),Y ; get Y value
|
||
|
|
clc
|
||
|
|
adc LETTER_Y
|
||
|
|
|
||
|
|
rts
|
||
|
|
|