_WCRTLINK void _WCI86FAR _CGRAPH _clearscreen( short area )
/*==========================================
This routine clears either the entire screen, the current viewport, or
the text window depending on the parameter. */
{
_InitState();
_CursorOff();
#if defined( _DEFAULT_WINDOWS )
_L2clearscreen( area );
#else
if( _GrMode ) {
_L2clearscreen( area );
} else {
switch( area ) {
case _GVIEWPORT: /* do nothing */
_ErrorStatus = _GRNOTINPROPERMODE;
break;
case _GWINDOW: /* clear current text window */
_TxtClear( _Tx_Row_Min, _Tx_Col_Min, _Tx_Row_Max, _Tx_Col_Max );
_settextposition( 1, 1 );
break;
case _GCLEARSCREEN: /* clear entire screen */
default: /* in all other cases */
_TxtClear( 0, 0, _CurrState->vc.numtextrows - 1,
_CurrState->vc.numtextcols - 1 );
_settextposition( 1, 1 );
}
}
#endif
_GrEpilog();
}
short _SetRows( short rows )
/*==========================
This function sets the number of text rows in the current mode. It only
affects the _VGA, _EGA, and _MCGA adapters. */
{
_ErrorStatus = _GROK;
_InitState(); // read the current machine state
if( _GrMode ) {
GrModeRows( rows );
} else {
TextModeRows( rows );
}
if( _ErrorStatus != _GROK ) {
return( 0 );
} else {
rows = *(char far *)_BIOS_data( ROWS ) + 1; // 0 for Hercules
if( rows == 1 ) rows = 25;
_CurrState->vc.numtextrows = rows;
if( !_GrMode ) {
_CalcNumPages(); // update the video configuration
}
_Tx_Row_Min = 0; // text window is now
_Tx_Col_Min = 0; // the full screen
_Tx_Row_Max = _CurrState->vc.numtextrows - 1;
_Tx_Col_Max = _CurrState->vc.numtextcols - 1;
_TextPos.row = 0; // set mode function
_TextPos.col = 0; // sets position to 0,0
_CurrVisualPage = 0;
_CurrActivePage = 0;
VideoInt( _BIOS_VIDEO_PAGE, 0, 0, 0 ); // set to page 0
return( _CurrState->vc.numtextrows );
}
}
_WCRTLINK short _WCI86FAR _CGRAPH _setactivepage( short pagenum )
/*================================================
This routine sets the active page for graphics output. */
{
short pos;
short prev;
_InitState();
if( _CurrState->vc.numvideopages == 1 ) {
if( pagenum != 0 ) {
_ErrorStatus = _GRINVALIDPARAMETER;
return( -1 );
} else {
return( 0 );
}
}
pagenum %= _CurrState->vc.numvideopages;
// #if defined( __386__ )
_CurrState->screen_seg = _CurrState->screen_seg_base;
_CurrState->screen_off = _CurrState->screen_off_base +
( ( _CurrState->page_size * pagenum ) << 4 );
// #else
// _CurrState->screen_seg = _CurrState->screen_seg_base +
// _CurrState->page_size * pagenum;
// _CurrState->screen_off = _CurrState->screen_off_base;
// #endif
pos = *(short __far *)_BIOS_data( CURSOR_POSN + 2 * pagenum );
_TextPos.row = pos >> 8; /* cursor position */
_TextPos.col = pos & 0xFF; /* on new page */
prev = _CurrActivePage;
_CurrActivePage = pagenum;
return( prev );
}
short _SetRows( short rows )
/*==========================
This function has no effect on Windows. It only re-initializes
the variable states. */
{
_ErrorStatus = _GROK;
_InitState(); // read the current machine state
rows = rows;
_clearscreen( _GCLEARSCREEN );
_Tx_Row_Min = 0; // text window is now
_Tx_Col_Min = 0; // the full screen
_Tx_Row_Max = _CurrState->vc.numtextrows - 1;
_Tx_Col_Max = _CurrState->vc.numtextcols - 1;
_TextPos.row = 0; // set mode function
_TextPos.col = 0; // sets position to 0,0
return( 0 );
}
