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cc65/libsrc/apple2/apple2-280-192-6.s
cuz 9a1bab361f Improvements by Oliver Schmidt
git-svn-id: svn://svn.cc65.org/cc65/trunk@3074 b7a2c559-68d2-44c3-8de9-860c34a00d81
2004-06-03 15:05:41 +00:00

813 lines
19 KiB
ArmAsm
Raw Blame History

;
; Graphics driver for the 280x192x6 mode on the Apple II
;
; Stefan Haubenthal <polluks@sdf.lonestar.org>
; Based on Maciej Witkowiak's circle routine
;
.include "zeropage.inc"
.include "tgi-kernel.inc"
.include "tgi-mode.inc"
.include "tgi-error.inc"
.include "apple2.inc"
.macpack generic
; ------------------------------------------------------------------------
; ROM entry points
TEXT := $F399 ; Return to text screen
HGR := $F3E2 ; Initialize and clear hi-res page 1.
HCLR := $F3F2 ; Clear the current hi-res screen to black.
HPOSN := $F411 ; Positions the hi-res cursor without
; plotting a point.
; Enter with (A) = Y-coordinate, and
; (Y,X) = X-coordinate.
HPLOT := $F457 ; Calls HPOSN and tries to plot a dot at
; the cursor's position. If you are
; trying to plot a non-white color at
; a complementary color position, no
; dot will be plotted.
HLIN := $F53A ; Draws a line from the last plotted
; point or line destination to:
; (X,A) = X-coordinate, and
; (Y) = Y-coordinate.
DRAW := $F601 ; Draws a shape. Enter with (Y,X) = the
; address of the shape table, and (A) =
; the rotation factor. Uses the current
; color.
SETHCOL := $F6EC ; Set the hi-res color to (X), where (X)
; must be between 0 and 7.
; ------------------------------------------------------------------------
; Header. Includes jump table and constants.
.segment "JUMPTABLE"
; First part of the header is a structure that has a magic and defines the
; capabilities of the driver
.byte $74, $67, $69 ; "tgi"
.byte TGI_API_VERSION ; TGI API version number
xres: .word 280 ; X resolution
yres: .word 192 ; Y resolution
.byte 8 ; Number of drawing colors
.byte 2 ; Number of screens available
.byte 8 ; System font X size
.byte 8 ; System font Y size
.res 4, $00 ; Reserved for future extensions
; Next comes the jump table. Currently all entries must be valid and may point
; to an RTS for test versions (function not implemented).
.word INSTALL
.word UNINSTALL
.word INIT
.word DONE
.word GETERROR
.word CONTROL
.word CLEAR
.word SETVIEWPAGE
.word SETDRAWPAGE
.word SETCOLOR
.word SETPALETTE
.word GETPALETTE
.word GETDEFPALETTE
.word SETPIXEL
.word GETPIXEL
.word LINE
.word BAR
.word CIRCLE
.word TEXTSTYLE
.word OUTTEXT
; ------------------------------------------------------------------------
; Data.
; Variables mapped to the zero page segment variables. Some of these are
; used for passing parameters to the driver.
X1 = ptr1
Y1 = ptr2
X2 = ptr3
Y2 = ptr4
RADIUS = tmp1
ADDR = tmp1
TEMP = tmp3
TEMP2 = tmp4
TEMP3 = sreg
TEMP4 = sreg+1
; Circle stuff
XX = ptr3 ; (2) CIRCLE
YY = ptr4 ; (2) CIRCLE
MaxO = sreg ; (overwritten by TEMP3+TEMP4, but restored from OG/OU anyway)
XS = regsave ; (2) CIRCLE
YS = regsave+2 ; (2) CIRCLE
; Absolute variables used in the code
.bss
ERROR: .res 1 ; Error code
; Line routine stuff (combined with CIRCLE to save space)
OGora: .res 2
OUkos: .res 2
Y3: .res 2
; Text output stuff
TEXTMAGX = $E7
TEXTMAGY = $E7
TEXTDIR = $F9
; Constants and tables
.rodata
DEFPALETTE: .byte $00, $05, $04, $01, $00, $08, $06, $01; 6 unique colors
SHAPE: .byte $64,$01,$D0,$00,$D5,$00,$DA,$00,$E0,$00,$EF,$00,$FE,$00,$0C,$01
.byte $19,$01,$1D,$01,$25,$01,$2D,$01,$3D,$01,$46,$01,$4B,$01,$52,$01
.byte $56,$01,$60,$01,$70,$01,$77,$01,$83,$01,$8E,$01,$9A,$01,$A7,$01
.byte $B6,$01,$BF,$01,$CE,$01,$DD,$01,$E2,$01,$E7,$01,$F9,$01,$03,$02
.byte $15,$02,$1F,$02,$32,$02,$42,$02,$52,$02,$5E,$02,$6C,$02,$79,$02
.byte $85,$02,$91,$02,$A1,$02,$A9,$02,$B2,$02,$BF,$02,$C5,$02,$D5,$02
.byte $E5,$02,$F4,$02,$00,$03,$10,$03,$1F,$03,$2D,$03,$35,$03,$44,$03
.byte $53,$03,$63,$03,$71,$03,$7B,$03,$85,$03,$91,$03,$97,$03,$A3,$03
.byte $B6,$03,$BF,$03,$C3,$03,$CF,$03,$DC,$03,$E4,$03,$F3,$03,$00,$04
.byte $0A,$04,$19,$04,$25,$04,$2A,$04,$32,$04,$3C,$04,$43,$04,$50,$04
.byte $5A,$04,$66,$04,$72,$04,$7E,$04,$87,$04,$94,$04,$9C,$04,$A8,$04
.byte $B4,$04,$C1,$04,$CC,$04,$DB,$04,$E6,$04,$EE,$04,$F3,$04,$FB,$04
.byte $04,$05,$1A,$05,$1F,$05,$24,$05,$29,$05,$22,$01,$00,$00,$00,$00
.byte $09,$89,$92,$92,$00,$36,$36,$16,$0E,$00,$0D,$FE,$6E,$96,$52,$00
.byte $69,$FE,$17,$2D,$2D,$1E,$1F,$17,$2D,$2D,$1E,$1F,$6E,$4E,$00,$09
.byte $8D,$3F,$BF,$0D,$15,$3F,$0E,$0D,$1E,$3F,$77,$71,$09,$00,$6D,$11
.byte $DF,$77,$09,$1E,$17,$4D,$3A,$DF,$4E,$29,$0E,$00,$A9,$1F,$6E,$1E
.byte $17,$0D,$0D,$1E,$DF,$0E,$6D,$0E,$00,$36,$96,$52,$00,$09,$1E,$17
.byte $36,$15,$0E,$0E,$00,$15,$0E,$36,$1E,$17,$4E,$01,$00,$09,$8D,$1F
.byte $1F,$0E,$2D,$1E,$17,$2D,$15,$1F,$1F,$4E,$4E,$01,$00,$89,$6E,$3A
.byte $3F,$77,$31,$56,$09,$00,$92,$8A,$F6,$0D,$00,$52,$89,$3F,$B7,$52
.byte $49,$00,$92,$92,$0E,$00,$49,$11,$17,$1E,$17,$1E,$56,$49,$01,$00
.byte $29,$AD,$DF,$33,$4D,$35,$1F,$1F,$2E,$4D,$FE,$1B,$0E,$2D,$4E,$00
.byte $31,$77,$36,$BE,$2D,$0E,$00,$29,$AD,$DF,$73,$49,$1E,$BF,$1E,$2E
.byte $2D,$75,$00,$2D,$2D,$BE,$3E,$4E,$FE,$1B,$0E,$2D,$4E,$00,$49,$3E
.byte $17,$0D,$FE,$33,$2D,$2D,$1E,$76,$01,$00,$2D,$2D,$DE,$1B,$2E,$2D
.byte $15,$36,$DF,$73,$2D,$4E,$00,$09,$2D,$DE,$BB,$4D,$3A,$3F,$6E,$09
.byte $FE,$1B,$0E,$2D,$4E,$00,$2D,$2D,$BE,$1E,$17,$36,$4E,$09,$00,$29
.byte $AD,$DF,$33,$4D,$F1,$3F,$17,$4D,$31,$DF,$73,$2D,$4E,$00,$29,$AD
.byte $DF,$33,$4D,$31,$3F,$77,$09,$1E,$DF,$2A,$75,$09,$00,$12,$16,$96
.byte $01,$00,$52,$B2,$F6,$0D,$00,$49,$3E,$17,$2D,$2D,$35,$3F,$3F,$3F
.byte $0E,$2D,$2D,$F5,$1B,$77,$4E,$09,$00,$12,$2D,$2D,$DE,$9B,$2D,$2D
.byte $96,$01,$00,$49,$15,$FF,$13,$2D,$2D,$AD,$3F,$3F,$3F,$2E,$2D,$2D
.byte $1E,$37,$4E,$09,$00,$29,$AD,$DF,$73,$09,$1E,$B6,$4E,$01,$00,$09
.byte $2D,$3E,$37,$2D,$3E,$FF,$2A,$2D,$2D,$F5,$3F,$3F,$0E,$2D,$1E,$4D
.byte $01,$00,$09,$15,$1F,$17,$4D,$31,$DF,$33,$2D,$2D,$FE,$1B,$6E,$09
.byte $0E,$00,$2D,$AD,$DF,$33,$4D,$F1,$3F,$37,$4D,$31,$DF,$33,$2D,$75
.byte $01,$00,$29,$AD,$DF,$33,$36,$4D,$11,$DF,$73,$2D,$4E,$00,$2D,$AD
.byte $DF,$6E,$31,$DF,$6E,$31,$DF,$17,$2D,$75,$01,$00,$2D,$2D,$DE,$1B
.byte $6E,$11,$3F,$37,$36,$2D,$2D,$0E,$00,$2D,$2D,$DE,$1B,$6E,$11,$3F
.byte $37,$36,$4E,$49,$00,$29,$AD,$DF,$33,$36,$4D,$35,$DF,$73,$2D,$75
.byte $00,$4D,$31,$DF,$33,$4D,$31,$3F,$3F,$6E,$09,$FE,$1B,$6E,$09,$0E
.byte $00,$2D,$1E,$36,$36,$17,$2D,$0E,$00,$49,$31,$36,$36,$DF,$73,$2D
.byte $4E,$00,$4D,$F1,$DF,$6E,$1E,$37,$0D,$15,$DF,$6E,$09,$0E,$00,$36
.byte $36,$36,$2D,$75,$00,$4D,$31,$FF,$37,$0D,$0D,$FE,$1F,$6E,$09,$FE
.byte $1B,$6E,$09,$0E,$00,$4D,$31,$DF,$33,$6D,$31,$1F,$1F,$6E,$29,$FE
.byte $1B,$6E,$09,$0E,$00,$29,$AD,$DF,$33,$4D,$31,$DF,$33,$4D,$31,$DF
.byte $73,$2D,$4E,$00,$2D,$AD,$DF,$33,$4D,$F1,$3F,$37,$36,$4E,$49,$00
.byte $29,$AD,$DF,$33,$4D,$31,$DF,$33,$0D,$0D,$1E,$DF,$0E,$6D,$0E,$00
.byte $2D,$AD,$DF,$33,$4D,$F1,$3F,$37,$0D,$15,$DF,$6E,$09,$0E,$00,$29
.byte $AD,$DF,$33,$4D,$3A,$77,$09,$FE,$1B,$0E,$2D,$4E,$00,$2D,$2D,$DE
.byte $36,$36,$76,$09,$00,$4D,$31,$DF,$33,$4D,$31,$DF,$33,$4D,$31,$DF
.byte $73,$2D,$4E,$00,$4D,$31,$DF,$33,$4D,$31,$DF,$33,$4D,$F1,$1F,$0E
.byte $4E,$01,$00,$4D,$31,$DF,$33,$4D,$31,$1F,$1F,$6E,$0D,$3E,$1F,$37
.byte $4D,$71,$00,$4D,$31,$DF,$73,$0D,$1E,$17,$0D,$15,$DF,$33,$4D,$71
.byte $00,$4D,$31,$DF,$73,$0D,$1E,$36,$76,$09,$00,$2D,$2D,$BE,$1E,$17
.byte $1E,$2E,$2D,$75,$00,$2D,$2D,$DE,$3B,$2E,$3E,$2E,$3E,$2E,$2D,$75
.byte $00,$72,$15,$0E,$15,$56,$00,$2D,$2D,$3E,$2E,$3E,$2E,$3E,$DF,$2A
.byte $2D,$75,$00,$49,$15,$3F,$17,$2D,$2D,$15,$3F,$3F,$3F,$4E,$2D,$3E
.byte $37,$2D,$3E,$6F,$49,$00,$92,$92,$49,$11,$3F,$3F,$4D,$09,$00,$76
.byte $96,$52,$00,$52,$2D,$35,$DF,$33,$4D,$31,$FF,$73,$6D,$0E,$00,$36
.byte $2D,$AD,$DF,$33,$4D,$31,$DF,$33,$2D,$75,$01,$00,$52,$2D,$DE,$33
.byte $76,$2D,$0E,$00,$49,$31,$DF,$2A,$2D,$FE,$1B,$6E,$09,$FE,$1B,$0E
.byte $2D,$75,$00,$52,$2D,$15,$DF,$33,$2D,$2D,$DE,$1B,$0E,$2D,$75,$00
.byte $09,$F5,$33,$8D,$3F,$77,$36,$4E,$01,$00,$52,$2D,$35,$DF,$33,$4D
.byte $31,$3F,$77,$09,$1E,$3F,$4D,$01,$00,$36,$2D,$AD,$DF,$33,$4D,$31
.byte $DF,$33,$4D,$71,$00,$16,$36,$36,$0E,$00,$09,$9E,$35,$36,$F6,$6F
.byte $01,$00,$36,$4D,$1E,$1F,$2E,$15,$1F,$6E,$71,$00,$35,$36,$36,$17
.byte $2D,$0E,$00,$12,$2D,$AD,$1F,$1F,$6E,$0D,$FE,$1F,$6E,$0D,$0E,$00
.byte $12,$2D,$15,$DF,$6E,$31,$DF,$6E,$71,$00,$52,$2D,$15,$DF,$33,$4D
.byte $31,$DF,$73,$2D,$4E,$00,$12,$2D,$AD,$DF,$33,$4D,$F1,$3F,$37,$6E
.byte $49,$00,$52,$2D,$35,$DF,$33,$4D,$31,$3F,$77,$09,$2E,$00,$12,$0D
.byte $AD,$DF,$37,$36,$4E,$49,$00,$52,$2D,$F5,$DB,$0E,$2D,$15,$DF,$13
.byte $2D,$75,$01,$00,$31,$17,$2D,$F5,$33,$76,$75,$00,$12,$4D,$31,$DF
.byte $33,$4D,$31,$FF,$73,$6D,$0E,$00,$12,$4D,$31,$DF,$33,$4D,$F1,$1F
.byte $0E,$4E,$01,$00,$12,$4D,$31,$DF,$33,$0D,$0D,$FE,$1F,$0E,$0D,$4E
.byte $00,$12,$4D,$F1,$1F,$0E,$15,$1F,$17,$4D,$71,$00,$12,$4D,$31,$DF
.byte $33,$4D,$31,$3F,$77,$09,$1E,$3F,$4D,$01,$00,$12,$2D,$2D,$1E,$17
.byte $1E,$17,$2D,$2D,$0E,$00,$09,$F5,$33,$1E,$0E,$76,$75,$00,$36,$36
.byte $36,$2E,$00,$AD,$AE,$17,$FE,$2A,$4E,$01,$00,$69,$11,$1F,$1F,$4E
.byte $B1,$92,$09,$00,$2D,$2D,$35,$3F,$3F,$37,$2D,$2D,$35,$3F,$3F,$37
.byte $2D,$2D,$35,$3F,$3F,$37,$2D,$2D,$75,$00,$40,$C0,$40,$18,$00,$40
.byte $C0,$40,$43,$00,$40,$C0,$40,$08,$00,$19,$00,$00
.code
; ------------------------------------------------------------------------
; INSTALL routine. Is called after the driver is loaded into memory. May
; initialize anything that has to be done just once. Is probably empty
; most of the time.
;
; Must set an error code: NO
;
INSTALL:
; ------------------------------------------------------------------------
; UNINSTALL routine. Is called before the driver is removed from memory. May
; clean up anything done by INSTALL but is probably empty most of the time.
;
; Must set an error code: NO
;
UNINSTALL:
rts
; ------------------------------------------------------------------------
; INIT: Changes an already installed device from text mode to graphics
; mode.
; Note that INIT/DONE may be called multiple times while the driver
; is loaded, while INSTALL is only called once, so any code that is needed
; to initializes variables and so on must go here. Setting palette and
; clearing the screen is not needed because this is called by the graphics
; kernel later.
; The graphics kernel will never call INIT when a graphics mode is already
; active, so there is no need to protect against that.
;
; Must set an error code: YES
;
INIT:
; Switch into graphics mode
jsr HGR
bit MIXCLR
; Done, reset the error code
lda #TGI_ERR_OK
sta ERROR
rts
; ------------------------------------------------------------------------
; DONE: Will be called to switch the graphics device back into text mode.
; The graphics kernel will never call DONE when no graphics mode is active,
; so there is no need to protect against that.
;
; Must set an error code: NO
;
DONE = TEXT
; ------------------------------------------------------------------------
; GETERROR: Return the error code in A and clear it.
GETERROR:
ldx #TGI_ERR_OK
lda ERROR
stx ERROR
rts
; ------------------------------------------------------------------------
; CONTROL: Platform/driver specific entry point.
;
; Must set an error code: YES
;
CONTROL:
lda #TGI_ERR_INV_FUNC
sta ERROR
rts
; ------------------------------------------------------------------------
; CLEAR: Clears the screen.
;
; Must set an error code: NO
;
CLEAR = HCLR
; ------------------------------------------------------------------------
; SETVIEWPAGE: Set the visible page. Called with the new page in A (0..n).
; The page number is already checked to be valid by the graphics kernel.
;
; Must set an error code: NO (will only be called if page ok)
;
SETVIEWPAGE:
tax
beq @L1
bit HISCR
rts
@L1: bit LOWSCR
rts
; ------------------------------------------------------------------------
; SETDRAWPAGE: Set the drawable page. Called with the new page in A (0..n).
; The page number is already checked to be valid by the graphics kernel.
;
; Must set an error code: NO (will only be called if page ok)
;
SETDRAWPAGE:
tax
beq @L1
lda #>$4000 ; Page 2
.byte $2C
@L1: lda #>$2000 ; Page 1
sta $E6
rts
; ------------------------------------------------------------------------
; SETCOLOR: Set the drawing color (in A). The new color is already checked
; to be in a valid range (0..maxcolor-1).
;
; Must set an error code: NO (will only be called if color ok)
;
SETCOLOR:
tax
jmp SETHCOL
; ------------------------------------------------------------------------
; SETPALETTE: Set the palette (not available with all drivers/hardware).
; A pointer to the palette is passed in ptr1. Must set an error if palettes
; are not supported
;
; Must set an error code: YES
;
SETPALETTE:
lda #TGI_ERR_INV_FUNC
sta ERROR
rts
; ------------------------------------------------------------------------
; GETPALETTE: Return the current palette in A/X. Even drivers that cannot
; set the palette should return the default palette here, so there's no
; way for this function to fail.
;
; Must set an error code: NO
;
GETPALETTE:
; ------------------------------------------------------------------------
; GETDEFPALETTE: Return the default palette for the driver in A/X. All
; drivers should return something reasonable here, even drivers that don't
; support palettes, otherwise the caller has no way to determine the colors
; of the (not changeable) palette.
;
; Must set an error code: NO (all drivers must have a default palette)
;
GETDEFPALETTE:
lda #<DEFPALETTE
ldx #>DEFPALETTE
rts
; ------------------------------------------------------------------------
; SETPIXEL: Draw one pixel at X1/Y1 = ptr1/ptr2 with the current drawing
; color. The coordinates passed to this function are never outside the
; visible screen area, so there is no need for clipping inside this function.
;
; Must set an error code: NO
;
SETPIXELCLIP:
lda Y1+1
bmi @finito ; y<0
lda X1+1
bmi @finito ; x<0
lda X1
ldx X1+1
sta ADDR
stx ADDR+1
ldx #ADDR
lda xres
ldy xres+1
jsr icmp ; ( x < xres ) ...
bcs @finito
lda Y1
ldx Y1+1
sta ADDR
stx ADDR+1
ldx #ADDR
lda yres
ldy yres+1
jsr icmp ; ... && ( y < yres )
bcc SETPIXEL
@finito:rts
SETPIXEL:
ldx X1
ldy X1+1
lda Y1
jmp HPLOT
; ------------------------------------------------------------------------
; GETPIXEL: Read the color value of a pixel and return it in A/X. The
; coordinates passed to this function are never outside the visible screen
; area, so there is no need for clipping inside this function.
GETPIXEL:
ldx X1
ldy X1+1
lda Y1
jsr HPOSN ; 1st pixel
HBASL = $26
HMASK = $30
ldx #$00
lda (HBASL),y
and HMASK
beq @L1
inx
@L1: stx tmp1
lda $E0 ; which neighbour
tax
and #$01
bne @odd
asl tmp1
inx
.byte $24
@odd: dex
ldy $E1
lda $E2
jsr HPOSN ; 2nd pixel
ldx #$00
lda (HBASL),y
and HMASK
beq @L2
inx
@L2: txa
ora tmp1
ldx #$00
rts
; ------------------------------------------------------------------------
; LINE: Draw a line from X1/Y1 to X2/Y2, where X1/Y1 = ptr1/ptr2 and
; X2/Y2 = ptr3/ptr4 using the current drawing color.
;
; Must set an error code: NO
;
LINE:
ldx X1
ldy X1+1
lda Y1
jsr HPOSN
lda X2
ldx X2+1
ldy Y2
jmp HLIN
; ------------------------------------------------------------------------
; BAR: Draw a filled rectangle with the corners X1/Y1, X2/Y2, where
; X1/Y1 = ptr1/ptr2 and X2/Y2 = ptr3/ptr4 using the current drawing color.
; Contrary to most other functions, the graphics kernel will sort and clip
; the coordinates before calling the driver, so on entry the following
; conditions are valid:
; X1 <= X2
; Y1 <= Y2
; (X1 >= 0) && (X1 < XRES)
; (X2 >= 0) && (X2 < XRES)
; (Y1 >= 0) && (Y1 < YRES)
; (Y2 >= 0) && (Y2 < YRES)
;
; Must set an error code: NO
;
BAR:
inc Y2
@L1: lda Y2
pha
lda Y1
sta Y2
jsr LINE
pla
sta Y2
inc Y1
cmp Y1
bne @L1
rts
; ------------------------------------------------------------------------
; CIRCLE: Draw a circle around the center X1/Y1 (= ptr1/ptr2) with the
; radius in tmp1 and the current drawing color.
;
; Must set an error code: NO
;
CIRCLE:
lda RADIUS
bne @L1
jmp SETPIXELCLIP ; Plot as a point
@L1: sta XX
; x = r;
lda #$00
sta XX+1
sta YY
sta YY+1
sta MaxO
sta MaxO+1
; y =0; mo=0;
lda X1
ldx X1+1
sta XS
stx XS+1
lda Y1
ldx Y1+1
sta YS
stx YS+1 ; XS/YS to remember the center
; while (y<x) {
@L013B: ldx #YY
lda XX
ldy XX+1
jsr icmp
bcc @L12
rts
@L12: ; plot points in 8 slices...
lda XS
add XX
sta X1
lda XS+1
adc XX+1
sta X1+1 ; x1 = xs+x
lda YS
add YY
sta Y1
pha
lda YS+1
adc YY+1
sta Y1+1 ; (stack)=ys+y, y1=(stack)
pha
jsr SETPIXELCLIP ; plot(xs+x,ys+y)
lda YS
sub YY
sta Y1
sta Y3
lda YS+1
sbc YY+1
sta Y1+1 ; y3 = y1 = ys-y
sta Y3+1
jsr SETPIXELCLIP ; plot(xs+x,ys-y)
pla
sta Y1+1
pla
sta Y1 ; y1 = ys+y
lda XS
sub XX
sta X1
lda XS+1
sbc XX+1
sta X1+1
jsr SETPIXELCLIP ; plot (xs-x,ys+y)
lda Y3
sta Y1
lda Y3+1
sta Y1+1
jsr SETPIXELCLIP ; plot (xs-x,ys-y)
lda XS
add YY
sta X1
lda XS+1
adc YY+1
sta X1+1 ; x1 = xs+y
lda YS
add XX
sta Y1
pha
lda YS+1
adc XX+1
sta Y1+1 ; (stack)=ys+x, y1=(stack)
pha
jsr SETPIXELCLIP ; plot(xs+y,ys+x)
lda YS
sub XX
sta Y1
sta Y3
lda YS+1
sbc XX+1
sta Y1+1 ; y3 = y1 = ys-x
sta Y3+1
jsr SETPIXELCLIP ; plot(xs+y,ys-x)
pla
sta Y1+1
pla
sta Y1 ; y1 = ys+x(stack)
lda XS
sub YY
sta X1
lda XS+1
sbc YY+1
sta X1+1
jsr SETPIXELCLIP ; plot (xs-y,ys+x)
lda Y3
sta Y1
lda Y3+1
sta Y1+1
jsr SETPIXELCLIP ; plot (xs-y,ys-x)
; og = mo+y+y+1
lda MaxO
ldx MaxO+1
add YY
tay
txa
adc YY+1
tax
tya
add YY
tay
txa
adc YY+1
tax
tya
add #$01
bcc @L0143
inx
@L0143: sta OGora
stx OGora+1
; ou = og-x-x+1
sub XX
tay
txa
sbc XX+1
tax
tya
sub XX
tay
txa
sbc XX+1
tax
tya
add #$01
bcc @L0146
inx
@L0146: sta OUkos
stx OUkos+1
; ++y
inc YY
bne @L0148
inc YY+1
@L0148: ; if (abs(ou)<abs(og))
lda OUkos
ldy OUkos+1
jsr abs
sta TEMP3
sty TEMP4
lda OGora
ldy OGora+1
jsr abs
ldx #TEMP3
jsr icmp
bpl @L0149
; { --x;
lda XX
sub #$01
sta XX
bcs @L014E
dec XX+1
@L014E: ; mo = ou; }
lda OUkos
ldx OUkos+1
jmp @L014G
; else { mo = og }
@L0149: lda OGora
ldx OGora+1
@L014G: sta MaxO
stx MaxO+1
; }
jmp @L013B
; ------------------------------------------------------------------------
; TEXTSTYLE: Set the style used when calling OUTTEXT. Text scaling in X and Y
; direction is passend in X/Y, the text direction is passed in A.
;
; Must set an error code: NO
;
TEXTSTYLE:
stx TEXTMAGX
sty TEXTMAGY
asl ; 16 <=> 90<39>
asl
asl
asl
sta TEXTDIR
rts
; ------------------------------------------------------------------------
; OUTTEXT: Output text at X/Y = ptr1/ptr2 using the current color and the
; current text style. The text to output is given as a zero terminated
; string with address in ptr3.
;
; Must set an error code: NO
;
OUTTEXT:
ldx X1
ldy X1+1
lda Y1
jsr HPOSN
lda SHAPE+2*99
add #<SHAPE
sta tmp3
lda SHAPE+2*99+1
adc #>SHAPE
sta tmp3+1
ldy #$00
@L1: lda (ptr3),y
beq @end
sub #$1F ; no controls
asl ; offset*2
tax
lda SHAPE,x
add #<SHAPE
sta tmp1
lda SHAPE+1,x
adc #>SHAPE
sta tmp1+1
tya
pha
ldx tmp1
ldy tmp1+1
lda TEXTDIR
jsr DRAW
ldx tmp3
ldy tmp3+1
lda TEXTDIR
jsr DRAW
pla
tay
iny
bne @L1
@end: rts
;-------------
; copies of some runtime routines
abs:
; a/y := abs(a/y)
cpy #$00
bpl @L1
; negay
clc
eor #$FF
adc #$01
pha
tya
eor #$FF
adc #$00
tay
pla
@L1: rts
icmp:
; compare a/y to zp,x
sta TEMP ; TEMP/TEMP2 - arg2
sty TEMP2
lda $00,x
pha
lda $01,x
tay
pla
tax
tya ; x/a - arg1 (a=high)
sub TEMP2
bne @L4
cpx TEMP
beq @L3
adc #$FF
ora #$01
@L3: rts
@L4: bvc @L3
eor #$FF
ora #$01
rts