4.51.2.4.46. ogSavePal()	Table of Contents	4.51.2.4.48. ogScaleBuf()

  procedure ogScale(var srcObject:ogSurface);

Will scale one surface to another surface. Pixel conversion will occur if the bitdepths or pixel formats are different.

• ogSurface.ogScaleBuf()

{ogScale.pas}
uses
  ObjGfx40, CRT;

var 
  buf:^ogSurface;
  pixfmt:ogPixelFmt;
  xx, yy, zz:uInt32;
  sX1, sY1, sX2, sY2, dX1, dY1, dX2, dY2:uInt32;
  
begin
  new(buf, ogInit);

  {Set the screen up as 1024x768 in true colour}
  if not screen^.ogCreate(1024, 768, OG_PIXFMT_32BPP) then
    begin
      writeln('Error setting video mode');
      halt
    end;

  {Create a 320x200 buffer with the same pixel format as the screen}
  screen^.ogGetPixFmt(pixfmt);
  buf^.ogCreate(320, 256, pixfmt);

  {Draw the RGB cube}
  zz:=1;
  repeat
    with screen^ do
    for yy:=0 to 255 do
      for xx:=0 to 255 do
        if (yy=0) or (xx=255) or (zz=253) then
        ogSetPixel(256+256+(xx div 2)-(zz div 4), 128+(yy div 2)+(zz div 4),
                   ogRGB(xx, 255-yy, zz));
    inc(zz,2);
  until (zz>255);

  {Now scale sections of the cube to other portions of the screen}
  with screen^ do
    begin
     {Since we deal with the coordinates several times, set them up
      in variables.  These could be passed directly into ogScaleBuf()
      if desired.}

      sX1 := 512-63;
      sY1 := 256-63;
      sX2 := 512+63;
      sY2 := 255+63;
      dX1 := 0;
      dY1 := 384;
      dX2 := 255;
      dY2 := 384+255;

      {Draw this line first since it goes behind the scaled area}
      ogLine(dX1, dY2, sX1-1, sY2+1, ogRGB(255, 255, 255));

      ogScaleBuf(dX1, dY1, dX2, dY2, screen^, sX1, sY1, sX2, sY2);

      ogLine(dX1, dY1, sX1, sY1, ogRGB(255, 255, 255));
      ogLine(dX2, dY1, sX2, sY1, ogRGB(255, 255, 255));
      ogLine(dX2, dY2, sX2, sY2, ogRGB(255, 255, 255));
      ogRect(sX1, sY1, sX2, sY2, ogRGB(255, 255, 255));
      ogRect(dX1, dY1, dX2, dY2, ogRGB(255, 255, 255));

      sX1 := 511-40;
      sY1 := 255+20;
      sX2 := 511+40;
      sY2 := 255+40;
      dX1 := 700;
      dY1 := 400;
      dX2 := 850;
      dY2 := 700;

      ogLine(dX2, dY2, sX2, sY2, ogRGB(255, 255, 255));
      ogScaleBuf(dX1, dY1, dX2, dY2, screen^, sX1, sY1, sX2, sY2);
      ogLine(dX1, dY2, sX1, sY2, ogRGB(255, 255, 255));
      ogLine(dX2, dY1, sX2, sY1, ogRGB(255, 255, 255));
      ogLine(dX1, dY1, sX1, sY1, ogRGB(255, 255, 255));
      ogRect(sX1, sY1, sX2, sY2, ogRGB(255, 255, 255));
      ogRect(dX1, dY1, dX2, dY2, ogRGB(255, 255, 255));

      sX1 := 512+75;
      sY1 := 150;
      sX2 := 512+110;
      sY2 := 190;
      dX1 := ogGetMaxX-200;
      dY1 := 0;
      dX2 := ogGetMaxX;
      dY2 := 250;

      ogLine(dX2, dY1, sX2+1, sY1, ogRGB(255, 255, 255));
      ogLine(dX2, dY2, sX2+1, sY2+1, ogRGB(255, 255, 255));
      ogScaleBuf(dX1, dY1, dX2, dY2, screen^, sX1, sY1, sX2, sY2);
      ogLine(dX1, dY2, sX1, sY2, ogRGB(255, 255, 255));
      ogLine(dX1, dY1, sX1, sY1, ogRGB(255, 255, 255));
      ogRect(sX1, sY1, sX2, sY2, ogRGB(255, 255, 255));
      ogRect(dX1, dY1, dX2, dY2, ogRGB(255, 255, 255));
    end; {with}

    for xx:=0 to 5 do
      begin
        {Scale the screen to the buffer}
        buf^.ogScale(screen^);
        {Draw a white rectangle around the edge of Buf}
        buf^.ogRect(0, 0, buf^.ogGetMaxX, buf^.ogGetMaxY, buf^.ogRGB(255, 255, 255));
        {Copy Buf back to the screen (in the upper left)}
        screen^.ogCopy(buf^);
      end;

  readKey;
  dispose(buf, ogDone);
end.

4.51.2.4.46. ogSavePal()	Table of Contents	4.51.2.4.48. ogScaleBuf()