dos33fsprogs/graphics/hgr/hgr_font/hgr_rectangle.s
2021-08-09 21:46:19 -04:00

309 lines
3.6 KiB
ArmAsm

; HGR Rectangle
; VGI Rectangle test
COLOR_MODE = TEMP0
OTHER_MASK = TEMP1
XRUN = TEMP2
div7_table = $B000
mod7_table = $B100
; FAST
;=================================
; Simple Rectangle
;=================================
; VGI_RCOLOR = P0
; VGI_RX1 = P1
; VGI_RY1 = P2
; VGI_RXRUN = P3
; VGI_RYRUN = P4
; VGI_RCOLOR2 = P5 ; only for dither
;==================================
; VGI Simple Rectangle
;==================================
vgi_simple_rectangle:
lda #0
sta COLOR_MODE
simple_rectangle_loop:
lda COLOR_MODE
beq simple_colors
bmi striped_colors
bpl handle_dither
simple_colors:
lda VGI_RCOLOR
asl ; nibble swap by david galloway
adc #$80
rol
asl
adc #$80
rol
sta VGI_RCOLOR
and #$f
tax
lda COLORTBL,X
sta HGR_COLOR
jmp done_colors
handle_dither:
lda COUNT
and #$1
beq deven_color
dodd_color:
lda VGI_RCOLOR
jmp dsave_color
deven_color:
lda VGI_RCOLOR2
dsave_color:
sta HGR_COLOR
inc COUNT
jmp done_colors
striped_colors:
; don't need to do anything here?
done_colors:
; get ROW into (GBASL)
ldx VGI_RX1 ; X1 into X
lda VGI_RY1 ; Y1 into A
ldy #0 ; always 0
jsr HPOSN ; (Y,X),(A) (values stores in HGRX,XH,Y)
; Y is already the RX1/7
; adjust color if in striped mode
lda COLOR_MODE
bpl not_striped
jsr swap_colors
not_striped:
; copy the XRUN
lda VGI_RXRUN
sta XRUN
inc XRUN ; needed because we compare with beq/bne
; check if narrow corner case where begin and end same block
; if RX%7 + XRUN < 8
ldx VGI_RX1
lda mod7_table,X
clc
adc XRUN
cmp #8
bcs not_corner
corner:
; want to use MASK of left_mask, MOD7 and 7-XRUN
lda mod7_table,X
tax
lda (GBASL),Y
eor HGR_BITS
and left_masks,X
ldx XRUN
and right_masks,X
eor (GBASL),Y
sta (GBASL),Y
jmp done_row ; that's all
not_corner:
; see if not starting on boundary
ldx VGI_RX1
lda mod7_table,X
beq draw_run
; handle not full left border
tax
lda (GBASL),Y
eor HGR_BITS
and left_masks,X
eor (GBASL),Y
sta (GBASL),Y
iny ; move to next
; adjust RUN length by 7- mod7
txa ; load mod7
eor #$ff
sec
adc #7
eor #$ff
sec
adc XRUN
sta XRUN
; lda HGR_BITS ; cycle colors for next
; jsr COLOR_SHIFT
jsr swap_colors
;no_shift:
; draw common
draw_run:
lda XRUN
cmp #7
bcc draw_right ; blt
lda HGR_BITS ; get color
sta (GBASL),Y ; store out
; jsr COLOR_SHIFT ; shift colors
iny ; move to next block
jsr swap_colors
lda XRUN ; take 7 off the run
sec
sbc #7
sta XRUN
jmp draw_run
; draw rightmost
draw_right:
beq done_row
; lda HGR_BITS
; jsr COLOR_SHIFT
; see if not starting on boundary
ldx XRUN
tax
lda (GBASL),Y
eor HGR_BITS
and right_masks,X
eor (GBASL),Y
sta (GBASL),Y
done_row:
inc VGI_RY1
dec VGI_RYRUN
;bne simple_rectangle_loop
beq done_done
jmp simple_rectangle_loop
done_done:
rts
;==========================
; swap colors
;==========================
swap_colors:
lda COLOR_MODE
bmi swap_colors_striped
lda HGR_BITS ; get color
jsr COLOR_SHIFT ; shift colors
rts
swap_colors_striped:
tya
and #1
bne swap_odd
lda VGI_RCOLOR
jmp swap_done
swap_odd:
lda VGI_RCOLOR2
swap_done:
sta HGR_BITS
rts
;=====================
; make /7 %7 tables
;=====================
vgi_init:
vgi_make_tables:
ldy #0
lda #0
ldx #0
div7_loop:
sta div7_table,Y
inx
cpx #7
bne div7_not7
clc
adc #1
ldx #0
div7_not7:
iny
bne div7_loop
ldy #0
lda #0
mod7_loop:
sta mod7_table,Y
clc
adc #1
cmp #7
bne mod7_not7
lda #0
mod7_not7:
iny
bne mod7_loop
rts
left_masks:
.byte $FF,$FE,$FC,$F8, $F0,$E0,$C0
right_masks:
.byte $81,$83,$87, $8F,$9F,$BF,$FF