2 ; Graphics driver for the 240x200x2 monochrome mode on the Atmos
4 ; Stefan Haubenthal <polluks@sdf.lonestar.org>
5 ; 2012-08-11, Greg King <greg.king5@verizon.net>
8 .include "zeropage.inc"
10 .include "tgi-kernel.inc"
11 .include "tgi-error.inc"
16 XSIZE = 6 ; System font width
17 YSIZE = 8 ; System font height
19 ; ------------------------------------------------------------------------
20 ; Header. Includes jump table and constants.
24 ; First part of the header is a structure that has a magic and defines the
25 ; capabilities of the driver
27 .byte $74, $67, $69 ; "tgi"
28 .byte TGI_API_VERSION ; TGI API version number
29 .addr $0000 ; Library reference
30 .word 240 ; X resolution
31 .word 200 ; Y resolution
32 .byte 2 ; Number of drawing colors
33 .byte 1 ; Number of screens available
34 .byte XSIZE ; System font X size
35 .byte YSIZE ; System font Y size
36 .word $011C ; Aspect ratio (based on 4/3 display)
37 .byte 0 ; TGI driver flags
39 ; Next comes the jump table. Currently all entries must be valid and may point
40 ; to an RTS for test versions (function not implemented).
61 .addr 0 ; IRQ entry is unused
63 ; ------------------------------------------------------------------------
66 ; Variables mapped to the zero page segment variables. Some of these are
67 ; used for passing parameters to the driver.
74 ; Absolute variables used in the code
78 ERROR: .res 1 ; Error code
79 MODE: .res 1 ; Graphics mode
81 ; Constants and tables
97 DEFPALETTE: .byte 0, 1
101 ; ------------------------------------------------------------------------
102 ; INSTALL routine. Is called after the driver is loaded into memory. May
103 ; initialize anything that has to be done just once. Is probably empty
106 ; Must set an error code: NO
111 ; ------------------------------------------------------------------------
112 ; UNINSTALL routine. Is called before the driver is removed from memory. May
113 ; clean up anything done by INSTALL but is probably empty most of the time.
115 ; Must set an error code: NO
121 ; ------------------------------------------------------------------------
122 ; INIT: Changes an already installed device from text mode to graphics
124 ; Note that INIT/DONE may be called multiple times while the driver
125 ; is loaded, while INSTALL is only called once, so any code that is needed
126 ; to initializes variables and so on must go here. Setting palette and
127 ; clearing the screen is not needed because this is called by the graphics
129 ; The graphics kernel will never call INIT when a graphics mode is already
130 ; active, so there is no need to protect against that.
132 ; Must set an error code: YES
137 ; Switch into graphics mode
141 ; Done, reset the error code
147 ; ------------------------------------------------------------------------
148 ; DONE: Will be called to switch the graphics device back into text mode.
149 ; The graphics kernel will never call DONE when no graphics mode is active,
150 ; so there is no need to protect against that.
152 ; Must set an error code: NO
157 ; ------------------------------------------------------------------------
158 ; GETERROR: Return the error code in A and clear it.
166 ; ------------------------------------------------------------------------
167 ; CONTROL: Platform/driver specific entry point.
169 ; Must set an error code: YES
178 ; ------------------------------------------------------------------------
179 ; CLEAR: Clears the screen.
181 ; Must set an error code: NO
186 ; ------------------------------------------------------------------------
187 ; SETVIEWPAGE: Set the visible page. Called with the new page in A (0..n).
188 ; The page number is already checked to be valid by the graphics kernel.
190 ; Must set an error code: NO (will only be called if page ok)
195 ; ------------------------------------------------------------------------
196 ; SETDRAWPAGE: Set the drawable page. Called with the new page in A (0..n).
197 ; The page number is already checked to be valid by the graphics kernel.
199 ; Must set an error code: NO (will only be called if page ok)
205 ; ------------------------------------------------------------------------
206 ; SETCOLOR: Set the drawing color (in A). The new color is already checked
207 ; to be in a valid range (0..maxcolor-1).
209 ; Must set an error code: NO (will only be called if color ok)
216 ; ------------------------------------------------------------------------
217 ; SETPALETTE: Set the palette (not available with all drivers/hardware).
218 ; A pointer to the palette is passed in ptr1. Must set an error if palettes
221 ; Must set an error code: YES
225 lda #TGI_ERR_INV_FUNC ; This resolution has no palette
229 ; ------------------------------------------------------------------------
230 ; GETPALETTE: Return the current palette in A/X. Even drivers that cannot
231 ; set the palette should return the default palette here, so there's no
232 ; way for this function to fail.
234 ; Must set an error code: NO
239 ; ------------------------------------------------------------------------
240 ; GETDEFPALETTE: Return the default palette for the driver in A/X. All
241 ; drivers should return something reasonable here, even drivers that don't
242 ; support palettes, otherwise the caller has no way to determine the colors
243 ; of the (not changeable) palette.
245 ; Must set an error code: NO (all drivers must have a default palette)
253 ; ------------------------------------------------------------------------
254 ; SETPIXEL: Draw one pixel at X1/Y1 = ptr1/ptr2 with the current drawing
255 ; color. The coordinates passed to this function are never outside the
256 ; visible screen area, so there is no need for clipping inside this function.
258 ; Must set an error code: NO
274 ; ------------------------------------------------------------------------
275 ; GETPIXEL: Read the color value of a pixel and return it in A/X. The
276 ; coordinates passed to this function are never outside the visible screen
277 ; area, so there is no need for clipping inside this function.
293 ; ------------------------------------------------------------------------
294 ; LINE: Draw a line from X1/Y1 to X2/Y2, where X1/Y1 = ptr1/ptr2 and
295 ; X2/Y2 = ptr3/ptr4 using the current drawing color.
297 ; Must set an error code: NO
320 ; ------------------------------------------------------------------------
321 ; BAR: Draw a filled rectangle with the corners X1/Y1, X2/Y2, where
322 ; X1/Y1 = ptr1/ptr2 and X2/Y2 = ptr3/ptr4 using the current drawing color.
323 ; Contrary to most other functions, the graphics kernel will sort and clip
324 ; the coordinates before calling the driver, so on entry the following
325 ; conditions are valid:
328 ; (X1 >= 0) && (X1 < XRES)
329 ; (X2 >= 0) && (X2 < XRES)
330 ; (Y1 >= 0) && (Y1 < YRES)
331 ; (Y2 >= 0) && (Y2 < YRES)
333 ; Must set an error code: NO
350 ; ------------------------------------------------------------------------
351 ; TEXTSTYLE: Set the style used when calling OUTTEXT. Text scaling in X and Y
352 ; direction is passend in X/Y, the text direction is passed in A.
354 ; Must set an error code: NO
361 ; ------------------------------------------------------------------------
362 ; OUTTEXT: Output text at X/Y = ptr1/ptr2 using the current color and the
363 ; current text style. The text to output is given as a zero terminated
364 ; string with address in ptr3.
366 ; Must set an error code: NO
373 lda #3 ; (Move graphics cursor; don't draw)