NOTES ON APPLE-II GRAPHICS COMMANDS
===================================
(those used in Akalabeth)


BASIC commands
--------------
GR              sets lo-res (40x40)   graphics mode with a 4-line text window
                at the bottom
HGR          75 sets hi-res (160x280) graphics mode with a 4-line text window
                at the bottom
HOME         80 clears text window and puts cursor at top left
INVERSE         black foreground (ie. INK 0), white background (ie. PAPER 7)
HTAB [1-255]    puts cursor on col 'c' relative to left margin of current row
     (0=256)    (1-40=row 'r', 41-80=row 'r+1', 81-120=row 'r+2', etc.)
NORMAL          white foreground (ie. INK 7), black background (ie. PAPER 0)
TEXT         85 sets full-screen text mode (24 rows x 40 cols)
VTAB [1-24]     puts cursor on row 'r' relative to top of screen (not window)


text window POKEs
-----------------
(saved in 65532-65535 on Spectrum)
POKE 32,[0-39]  left margin
POKE 33,[1-40]  width
POKE 34,[0-23]  top margin
POKE 35,[0-24]  bottom margin
(line#s in AKALABETH_AppleII.BAS)
  69 ... POKE 33,29: POKE 34,20 (usual setting)
1091 ... POKE 33,40 (for player stats display)
1091 ... POKE 33,29
1096 ... POKE 33,40 (for player stats display)
1096 ... POKE 33,29
6000 ... POKE 33,40 (for "passing" message
60080 ...            POKE 34,12: POKE 35,15: (for inventory stats)


other POKEs
-----------
POKE -16368,0   "resets keyboard strobe" (not needed for Spectrum)


CALLs
-----
-868    clear to EOL
-936    same as HOME
62450   clears GRAPHICS window to black (doesn't affect TEXT window?)