+ page flipping for all VESA modes.

   (important note: The VESAModeInfo structure returns the MAXIMUM
    number of image pages, and not the actual available number of
    pages (cf. VBE 3.0 specification), that is the reason why
    SetVisualPage() has so much checking).

rtl/go32v2/vesa.inc

@@ -62,6 +62,7 @@ const
 var
 
   BytesPerLine: word;              { Number of bytes per scanline }
+  YOffset : word;                  { Pixel offset for VESA page flipping }
 
   { window management }
   ReadWindow : byte;      { Window number for reading. }
@@ -73,6 +74,8 @@ var
 
   BankShift : word;       { address to shift by when switching banks. }
 
+  ScanLines: word;        { maximum number of scan lines for mode }
+
 function hexstr(val : longint;cnt : byte) : string;
 const
   HexTbl : array[0..15] of char='0123456789ABCDEF';
@@ -411,6 +414,7 @@ end;
        if (Y < StartYViewPort) or (Y > (StartYViewPort + ViewHeight)) then
          exit;
      end;
+     Y := Y + YOffset; { adjust pixel for correct virtual page }
      offs := longint(y) * BytesPerLine + x;
      SetWriteBank(integer(offs shr 16));
      mem[WinWriteSeg : word(offs)] := byte(color);
@@ -421,6 +425,7 @@ end;
      offs : longint;
      col : byte;
   begin
+     y := y + YOffset;
      offs := longint(y) * BytesPerLine + x;
      SetWriteBank(integer(offs shr 16));
      Case CurrentWriteMode of
@@ -454,7 +459,7 @@ end;
      offs : longint;
   begin
      X:= X + StartXViewPort;
-     Y:= Y + StartYViewPort;
+     Y:= Y + StartYViewPort + YOffset;
      offs := longint(y) * BytesPerLine + x;
      SetReadBank(integer(offs shr 16));
      GetPixVESA256:=mem[WinReadSeg : word(offs)];
@@ -483,6 +488,7 @@ end;
                 StartXViewPort+ViewWidth, StartYViewPort+ViewHeight) then
             exit;
       end;
+    Y:= Y + YOffset; { Adjust for correct virtual page }
     {$ifdef logging}
     LogLn('hline '+strf(x)+' - '+strf(x2)+' on '+strf(y)+' in mode '+strf(currentwritemode));
     {$endif logging}
@@ -758,6 +764,8 @@ end;
                 StartXViewPort+ViewWidth, StartYViewPort+ViewHeight) then
             exit;
       end;
+    Y := Y + YOffset;
+    Y2 := Y2 + YOffset; { adjust for current virtual page }
     Col := Byte(CurrentColor);
     {$ifdef logging}
     LogLn('vline '+strf(y)+' - '+strf(y2)+' on '+strf(x)+' in mode '+strf(currentwritemode));
@@ -907,6 +915,7 @@ end;
        if (Y < StartYViewPort) or (Y > (StartYViewPort + ViewHeight)) then
          exit;
      end;
+     Y := Y + YOffset; { adjust pixel for correct virtual page }
      offs := longint(y) * BytesPerLine + 2*x;
      SetWriteBank(integer(offs shr 16));
      memW[WinWriteSeg : word(offs)] := color;
@@ -926,6 +935,7 @@ end;
        if (Y < StartYViewPort) or (Y > (StartYViewPort + ViewHeight)) then
          exit;
      end;
+     Y := Y + YOffset; { adjust pixel for correct virtual page }
     offs := longint(y) * BytesPerLine + 2*x;
     SetWriteBank(integer(offs shr 16));
     memW[WinWriteSeg : word(offs)] := color;
@@ -936,7 +946,7 @@ end;
      offs : longint;
   begin
      X:= X + StartXViewPort;
-     Y:= Y + StartYViewPort;
+     Y:= Y + StartYViewPort + YOffset;
      offs := longint(y) * BytesPerLine + 2*x;
      SetReadBank(integer(offs shr 16));
      GetPixVESA32k:=memW[WinReadSeg : word(offs)];
@@ -947,7 +957,7 @@ end;
      offs : longint;
   begin
      X:= X + StartXViewPort;
-     Y:= Y + StartYViewPort;
+     Y:= Y + StartYViewPort + YOffset;
      offs := longint(y) * BytesPerLine + 2*x;
      SetReadBank(integer(offs shr 16));
      GetPixVESA64k:=memW[WinReadSeg : word(offs)];
@@ -958,6 +968,7 @@ end;
      offs : longint;
      col : word;
   begin
+     y:= Y + YOffset;
      offs := longint(y) * BytesPerLine + 2*x;
      SetWriteBank(integer((offs shr 16) and $ff));
      Case CurrentWriteMode of
@@ -991,6 +1002,7 @@ end;
      offs : longint;
      Col : word;
   begin
+     Y:= y + YOffset;
      offs := longint(y) * BytesPerLine + 2*x;
      SetWriteBank(integer(offs shr 16));
      Case CurrentWriteMode of
@@ -1038,6 +1050,7 @@ end;
        if (Y < StartYViewPort) or (Y > (StartYViewPort + ViewHeight)) then
          exit;
      end;
+     Y := Y + YOffset; { adjust pixel for correct virtual page }
      { }
      offs := longint(y) * BytesPerLine + (x div 8);
      SetWriteBank(integer(offs shr 16));
@@ -1061,7 +1074,7 @@ end;
      shift: byte;
   Begin
     X:= X + StartXViewPort;
-    Y:= Y + StartYViewPort;
+    Y:= Y + StartYViewPort + YOffset;
     offset := longint(Y) * BytesPerLine + (x div 8);
     SetReadBank(integer(offset shr 16));
     Port[$3ce] := 4;
@@ -1084,6 +1097,7 @@ end;
      dummy : byte;
      Color : word;
   begin
+    y:= Y + YOffset;
     case CurrentWriteMode of
       XORPut:
         begin
@@ -1622,91 +1636,159 @@ end;
  {*                     VESA Modes inits                                 *}
  {************************************************************************}
 
+{$IFDEF DPMI}
+
+  {******************************************************** }
+  { Function GetMaxScanLines()                              }
+  {-------------------------------------------------------- }
+  { This routine returns the maximum number of scan lines   }
+  { possible for this mode. This is done using the Get      }
+  { Scan Line length VBE function.                          }
+  {******************************************************** }
+  function GetMaxScanLines: word;
+   var
+    regs : TDPMIRegisters;
+   begin
+     FillChar(regs, sizeof(regs), #0);
+     { play it safe, call the real mode int, the 32-bit entry point }
+     { may not be defined as stated in VBE v3.0                     }
+     regs.eax := $4f06; {_ setup function      }
+     regs.ebx := $0001; { get scan line length }
+     RealIntr($10, regs);
+     GetMaxScanLines := (regs.edx and $0000ffff);
+   end;
+
+{$ELSE}
+
+  function GetMaxScanLines: word; assembler;
+     asm
+      mov ax, 4f06h
+      mov bx, 0001h
+      int 10h
+      mov ax, dx
+   end;
+
+{$ENDIF}
+
  procedure Init1280x1024x64k; {$ifndef fpc}far;{$endif fpc}
   begin
     SetVesaMode(m1280x1024x64k);
+    { Get maximum number of scanlines for page flipping }
+    ScanLines := GetMaxScanLines;
   end;
 
  procedure Init1280x1024x32k; {$ifndef fpc}far;{$endif fpc}
   begin
     SetVESAMode(m1280x1024x32k);
+    { Get maximum number of scanlines for page flipping }
+    ScanLines := GetMaxScanLines;
   end;
 
  procedure Init1280x1024x256; {$ifndef fpc}far;{$endif fpc}
   begin
     SetVESAMode(m1280x1024x256);
+    { Get maximum number of scanlines for page flipping }
+    ScanLines := GetMaxScanLines;
   end;
 
 
  procedure Init1280x1024x16; {$ifndef fpc}far;{$endif fpc}
   begin
     SetVESAMode(m1280x1024x16);
+    { Get maximum number of scanlines for page flipping }
+    ScanLines := GetMaxScanLines;
   end;
 
  procedure Init1024x768x64k; {$ifndef fpc}far;{$endif fpc}
   begin
     SetVESAMode(m1024x768x64k);
+    { Get maximum number of scanlines for page flipping }
+    ScanLines := GetMaxScanLines;
   end;
 
  procedure Init640x480x32k; {$ifndef fpc}far;{$endif fpc}
   begin
     SetVESAMode(m640x480x32k);
+    { Get maximum number of scanlines for page flipping }
+    ScanLines := GetMaxScanLines;
   end;
 
  procedure Init1024x768x256; {$ifndef fpc}far;{$endif fpc}
   begin
     SetVESAMode(m1024x768x256);
+    { Get maximum number of scanlines for page flipping }
+    ScanLines := GetMaxScanLines;
   end;
 
  procedure Init1024x768x16; {$ifndef fpc}far;{$endif fpc}
   begin
     SetVESAMode(m1024x768x16);
+    { Get maximum number of scanlines for page flipping }
+    ScanLines := GetMaxScanLines;
   end;
 
  procedure Init800x600x64k; {$ifndef fpc}far;{$endif fpc}
   begin
     SetVESAMode(m800x600x64k);
+    { Get maximum number of scanlines for page flipping }
+    ScanLines := GetMaxScanLines;
   end;
 
  procedure Init800x600x32k; {$ifndef fpc}far;{$endif fpc}
   begin
     SetVESAMode(m800x600x32k);
+    { Get maximum number of scanlines for page flipping }
+    ScanLines := GetMaxScanLines;
   end;
 
  procedure Init800x600x256; {$ifndef fpc}far;{$endif fpc}
   begin
     SetVESAMode(m800x600x256);
+    { Get maximum number of scanlines for page flipping }
+    ScanLines := GetMaxScanLines;
   end;
 
  procedure Init800x600x16; {$ifndef fpc}far;{$endif fpc}
   begin
     SetVesaMode(m800x600x16);
+    { Get maximum number of scanlines for page flipping }
+    ScanLines := GetMaxScanLines;
   end;
 
  procedure Init640x480x64k; {$ifndef fpc}far;{$endif fpc}
   begin
     SetVESAMode(m640x480x64k);
+    { Get maximum number of scanlines for page flipping }
+    ScanLines := GetMaxScanLines;
   end;
 
 
  procedure Init640x480x256; {$ifndef fpc}far;{$endif fpc}
   begin
     SetVESAMode(m640x480x256);
+    { Get maximum number of scanlines for page flipping }
+    ScanLines := GetMaxScanLines;
   end;
 
  procedure Init640x400x256; {$ifndef fpc}far;{$endif fpc}
   begin
     SetVESAMode(m640x400x256);
+    { Get maximum number of scanlines for page flipping }
+    ScanLines := GetMaxScanLines;
   end;
 
  procedure Init320x200x64k; {$ifndef fpc}far;{$endif fpc}
   begin
     SetVESAMode(m320x200x64k);
+    { Get maximum number of scanlines for page flipping }
+    ScanLines := GetMaxScanLines;
   end;
 
  procedure Init320x200x32k; {$ifndef fpc}far;{$endif fpc}
   begin
     SetVESAMode(m320x200x32k);
+    { Get maximum number of scanlines for page flipping }
+    ScanLines := GetMaxScanLines;
   end;
 
 
@@ -1936,20 +2018,54 @@ end;
  { Note: These routines, according  to the VBE3 specification, will NOT   }
  { work with the 24 bpp modes, because of the alignment.                  }
  {************************************************************************}
+
+  {******************************************************** }
+  { Procedure SetVisualVESA()                               }
+  {-------------------------------------------------------- }
+  { This routine changes the page which will be displayed   }
+  { on the screen, since the method has changed somewhat    }
+  { between VBE versions , we will use the old method where }
+  { the new pixel offset is used to display different pages }
+  {******************************************************** }
  procedure SetVisualVESA(page: word); {$ifndef fpc}far;{$endif fpc}
-  { two page support... }
+  var
+   newStartVisible : word;
   begin
     if page > HardwarePages then exit;
+    newStartVisible := (MaxY+1)*page;
+    if newStartVisible > ScanLines then exit;
+    asm
+      mov ax, 4f07h
+      mov bx, 0000h   { set display start }
+      mov cx, 0000h   { pixel zero !      }
+      mov dx, [NewStartVisible]  { new scanline }
+{$ifdef fpc}
+      push    ebp
+{$endif}
+      int     10h
+{$ifdef fpc}
+      pop     ebp
+{$endif}
+    end;
   end;
 
  procedure SetActiveVESA(page: word); {$ifndef fpc}far;{$endif fpc}
-  { two page support... }
   begin
+    { video offset is in pixels under VESA VBE! }
+    { This value is reset after a mode set to page ZERO = YOffset = 0 ) }
+    YOffset := (MaxY+1)*page;
   end;
 
 {
 $Log$
-Revision 1.5  1999-12-02 22:34:14  pierre
+Revision 1.6  1999-12-09 02:06:00  carl
+  + page flipping for all VESA modes.
+   (important note: The VESAModeInfo structure returns the MAXIMUM
+    number of image pages, and not the actual available number of
+    pages (cf. VBE 3.0 specification), that is the reason why
+    SetVisualPage() has so much checking).
+
+Revision 1.5  1999/12/02 22:34:14  pierre
  * avoid FPC problem in array of char comp
 
 Revision 1.4  1999/11/30 02:25:15  carl