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cc65/libsrc/atmos/atmos-240-200-2.s
uz 5304a8149e Changes to the TGI driver API:
* Removed CIRCLE
  * Aspect ratio is a new header variable
  * Removed the reserved bytes - it's easier to bump the API version
  * Clipping is done completely in the wrapper



git-svn-id: svn://svn.cc65.org/cc65/trunk@4396 b7a2c559-68d2-44c3-8de9-860c34a00d81
2009-10-29 20:13:56 +00:00

402 lines
9.0 KiB
ArmAsm

;
; Graphics driver for the 240x200x2 mode on the Atmos
;
; Stefan Haubenthal <polluks@sdf.lonestar.org>
;
.include "zeropage.inc"
.include "tgi-kernel.inc"
.include "tgi-mode.inc"
.include "tgi-error.inc"
.include "atmos.inc"
.macpack generic
; ------------------------------------------------------------------------
; 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
.word 240 ; X resolution
.word 200 ; Y resolution
.byte 2 ; Number of drawing colors
.byte 1 ; Number of screens available
xsize: .byte 6 ; System font X size
.byte 8 ; System font Y size
.word $100 ; Aspect ratio
; Next comes the jump table. Currently all entries must be valid and may point
; to an RTS for test versions (function not implemented).
.addr INSTALL
.addr UNINSTALL
.addr INIT
.addr DONE
.addr GETERROR
.addr CONTROL
.addr CLEAR
.addr SETVIEWPAGE
.addr SETDRAWPAGE
.addr SETCOLOR
.addr SETPALETTE
.addr GETPALETTE
.addr GETDEFPALETTE
.addr SETPIXEL
.addr GETPIXEL
.addr LINE
.addr BAR
.addr TEXTSTYLE
.addr OUTTEXT
.addr 0 ; IRQ entry is unused
; ------------------------------------------------------------------------
; 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
; Absolute variables used in the code
.bss
ERROR: .res 1 ; Error code
MODE: .res 1 ; Graphics mode
; Constants and tables
PARAM1 = $2E1
PARAM2 = $2E3
PARAM3 = $2E5
TEXT = $EC21
HIRES = $EC33
CURSET = $F0C8
CURMOV = $F0FD
DRAW = $F110
CHAR = $F12D
POINT = $F1C8
PAPER = $F204
INK = $F210
.rodata
DEFPALETTE: .byte $00, $07
.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 HIRES
; 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:
sta $213
lda #TGI_ERR_OK
sta ERROR
rts
; ------------------------------------------------------------------------
; CLEAR: Clears the screen.
;
; Must set an error code: NO
;
CLEAR = HIRES
; ------------------------------------------------------------------------
; 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:
; ------------------------------------------------------------------------
; 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:
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:
sta MODE
rts
; ------------------------------------------------------------------------
; 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:
ldy #0
lda (ptr1),y
sta PARAM1
jsr PAPER
ldy #1
lda (ptr1),y
sta PARAM1
jsr INK
lda #TGI_ERR_OK
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
;
SETPIXEL:
lda MODE
mymode: sta PARAM3
lda X1
sta PARAM1
lda Y1
sta PARAM2
lda #0
sta PARAM1+1
sta PARAM2+1
jmp CURSET
; ------------------------------------------------------------------------
; 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:
lda X1
sta PARAM1
lda Y1
sta PARAM2
lda #0
sta PARAM1+1
sta PARAM2+1
jsr POINT
lda PARAM1
and #%00000001
ldx #0
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:
jsr SETPIXEL
lda X2
sub X1
sta PARAM1
lda X2+1
sbc X1+1
sta PARAM1+1
lda Y2
sub Y1
sta PARAM2
lda Y2+1
sbc Y1+1
sta PARAM2+1
lda MODE
sta PARAM3
jmp DRAW
; ------------------------------------------------------------------------
; 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
; ------------------------------------------------------------------------
; 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:
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:
lda X1
sta PARAM1
lda Y1
sta PARAM2
lda #3
sta PARAM3
jsr CURSET
ldy #0
@next: lda (ptr3),y
beq @end
sta PARAM1
lda #0
sta PARAM2
lda MODE
sta PARAM3
tya
pha
jsr CHAR
lda xsize
sta PARAM1
lda #0
sta PARAM2
lda #3
sta PARAM3
jsr CURMOV
pla
tay
iny
bne @next
@end: rts