; ; Graphics driver for the 240x200x2 monochrome mode on the Atmos ; ; Stefan Haubenthal ; 2012-08-11, Greg King ; .include "zeropage.inc" .include "tgi-kernel.inc" .include "tgi-error.inc" .include "atmos.inc" .macpack generic XSIZE = 6 ; System font width YSIZE = 8 ; System font height ; ------------------------------------------------------------------------ ; 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 .byte XSIZE ; System font X size .byte YSIZE ; System font Y size .word $011C ; Aspect ratio (based on 4/3 display) .byte 0 ; TGI driver flags ; 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 ; 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 0, 1 .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: lda #TGI_ERR_INV_FUNC ; This resolution has no palette 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 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 Y1 sta PARAM2 lda MODE mymode: sta PARAM3 lda X1 sta PARAM1 lda #0 sta PARAM1+1 sta PARAM2+1 sta PARAM3+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 ldx #>0 stx PARAM3+1 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 Y1 sub #(YSIZE - 1) sta PARAM2 lda #3 ; (Move graphics cursor; don't draw) jsr mymode ldy #0 @next: lda (ptr3),y beq @end sta PARAM1 lda #0 sta PARAM2 sta PARAM1+1 sta PARAM2+1 sta PARAM3+1 lda MODE sta PARAM3 tya pha jsr CHAR lda #XSIZE sta PARAM1 lda #0 sta PARAM2 sta PARAM1+1 sta PARAM2+1 sta PARAM3+1 lda #3 sta PARAM3 jsr CURMOV pla tay iny bne @next @end: rts