BIOS Graphics Functions
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Graphics Init
BBBA GRA_INITIALIZE
Graphics Normal Drawing Functions
BBC0 GRA_MOVE_ABSOLUTE ;in: de=x, hl=y ;\set current coordinate BBC3 GRA_MOVE_RELATIVE ;in: de=x, hl=y ;/ BBEA GRA_PLOT_ABSOLUTE ;in: de=x, hl=y ;\draw pixel at specified coordinate BBED GRA_PLOT_RELATIVE ;in: de=x, hl=y ;/ BBF6 GRA_LINE_ABSOLUTE ;in: de=x, hl=y ;\draw line from current coordinate BBF9 GRA_LINE_RELATIVE ;in: de=x, hl=y ;/to specified target coordinate BBF0 GRA_TEST_ABSOLUTE ;in: de=x, hl=y, out: A=color (0..15) of pixel BBF3 GRA_TEST_RELATIVE ;in: de=x, hl=y, out: A=color (0..15) of pixel BBC6 GRA_ASK_CURSOR ;out: de=x, hl=y ;-get current coordinate BBFC GRA_WR_CHAR ;in: A=char ;-draw char at current coordinate
Graphics Pen/Paper
BBDE GRA_SET_PEN ;in: A=color (0..15) for PLOT/LINE/WR_CHAR BBE1 GRA_GET_PEN ;out: A=color (0..15) BBE4 GRA_SET_PAPER ;in: A=color (0..15) for CLEAR_WINDOW/WR_CHAR BBE7 GRA_GET_PAPER ;out: A=color (0..15
Graphics Origin
BBC9 GRA_SET_ORIGIN ;in: de=x, hl=y (also does MOVE 0,0) BBCC GRA_GET_ORIGIN ;out: de=x, hl=y
Normally, coordinate 0,0 is the lower-left of the screen. By changing the origin it can be moved, for example, to the middle of the screen.
Graphics Window
BBCF GRA_SET_WIN_WIDTH ;in: de=x1/left, hl=x2/right BBD2 GRA_SET_WIN_HEIGHT ;in: de=y1/top, hl=y2/bottom BBD5 GRA_GET_WIN_WIDTH ;out: de=x1/left, hl=x2/right BBD8 GRA_GET_WIN_HEIGHT ;out: de=y1/top, hl=y2/bottom BBDB GRA_CLEAR_WINDOW ;fill window by PAPER (also does MOVE 0,0)
Drawing operations are clipped to the window region. The x1/x2 values are rounded to byte-boundaries in VRAM.
Graphics Hooks
BBBD GRA_RESET_HOOKS ;out: [BDDC+00h..0Ah]=Default jump opcodes/addresses BDDC HOOK_GRA_PLOT ;in: de=x, hl=y ;\JP NNNNh opcodes, BDDF HOOK_GRA_TEST ;in: de=x, hl=y, out: A=color ; with NNNNh in LO ROM BDE2 HOOK_GRA_LINE ;in: de=x, hl=y ;/(which must be on)
New Graphics Functions (664 and up only)
BD43 GRA_DEFAULT_664 ;SCR_WRITE=?, BACK=00h,FIRST=FFh,MASK=FFh BD46 GRA_SET_BACK_664 ;A=background mode (FFh=transparent) BD49 GRA_SET_FIRST_664 ;in: A=flag (00h,FFh;1st pix of LINE) BD4C GRA_SET_LINE_MASK_664 ;in: A=mask BD4F GRA_FROM_USER_664 ;in: de=x, hl=y, out: de,hl=real x,y BD52 GRA_FILL_664 ;in: A=color,hl=buf,de=bufsize, out:cy=0=err