{APLGR/G.INC enables calling graphics routines in Apple's
 ROMs from Turbo Pascal programs.
 Requires the PCPI Z80 card (Applicard).
 Copyright 1984 by N.T.Carnevale.
 Permission granted for nonprofit use.}

{Include after PCP and before APLGR/L or APLGR/H}

{contains these routines used by both hi- & lores graphics:
PROCEDURE _setpartition(part:partition);
PROCEDURE _selectpage(pagenum:integer);
PROCEDURE textscreen(pagenum:integer);
}

CONST
  _BPL=40;  {# bytes/line of hi or lo res display}

  {software switches for control of graphics features}
  _GRFX=$C050;        _TXT=$C051;
  _FULSCRN=$C052;     _MXD=$C053;
  _PG1=$C054;         _PG2=$C055;
  _LRS=$C056;         _HRS=$C057;

  {temporary storage for parameters}
  _AREG=$9000;  _YREG=$9001;  _LOCXX=$9002;  _XREG=$9002;

TYPE
  partition=(FULLSCREEN,MIXED);
  _screenmode=(TEXT,GRAPHICS);

(*********************************************************)

PROCEDURE _setpartition(part:partition);
{switch between full screen graphics and mixed text/graphics}
BEGIN
  CASE part OF
    FULLSCREEN:  _wrhostbyte(_FULSCRN,0);
    MIXED:  _wrhostbyte(_MXD,0);
  END;
END;

PROCEDURE _selectpage(pagenum:integer);
{switch to specified graphics page}
BEGIN
  IF pagenum=1 THEN _wrhostbyte(_PG1,0)
  ELSE IF pagenum=2 THEN _wrhostbyte(_PG2,0)
  ELSE writeln('There is no page ',pagenum);
END;

PROCEDURE textscreen(pagenum:integer);
{switch to specified text screen}
BEGIN
  _selectpage(pagenum);
  _wrhostbyte(_TXT,0);
END;

FUNCTION _inrange(n,lolimit,hilimit:integer):boolean;
{test for value outside of limits--used to prevent drawing
 outside the screen boundaries}
BEGIN
  IF (n>=lolimit) AND (n<=hilimit) THEN _inrange:=TRUE
  ELSE _inrange:=FALSE;
END;

{end of APLGR/G}