procedure TestMaskScanline1;
var
k, x,y, x1,x2,y1,y2, pc: integer;
polysel:ppointarray;
mask:Tiemask;
p: pbyte;
bpp: integer;
begin
  case ImageEnView1.IEBitmap.PixelFormat of
    ie8g: bpp := 1;
    ie24RGB: bpp := 3;
    else
    exit;
  end;

  imageenview1.proc.GetReSel(x1,y1,x2,y2,polysel, pc, mask);
  for y := y1 to y2 do
  begin
    p := imageenview1.ieBitmap.scanline[y];
    inc(p, x1 * bpp);
    for x:= x1 to x2 do
    begin
      if mask.GetPixel(x, y)>0 then
         p^ := 255;
      for k := 1 to bpp do
        inc(p);
    end;
  end;

end;

// Set all selected pixels red
var
  x, y: Integer;
  pSel: pbyte;
  pPix: PRGB;
begin
  if ImageEnView1.SelectionMask.IsEmpty then
    raise Exception.create( 'Nothing selected' );

  if ImageEnView1.IEBitmap.PixelFormat <> ie24RGB then
    raise Exception.create( 'Not 24bit' );

  // Process selected area
  for y := 0 to ImageEnView1.SelectionMask.Height - 1 do
  begin
    pSel := ImageEnView1.SelectionMask.ScanLine[ y ];
    pPix := ImageEnView1.IEBitmap.ScanLine[ y ];

    case ImageEnView1.SelectionMask.BitsPerPixel of
      1:
        for x := 0 to ImageEnView1.SelectionMask.Width - 1 do
        begin
          // 1 Bit mask (values are 0 or 1)
          if (pbytearray(pSel)^[x shr 3] and iebitmask1[x and $7]) <> 0 then
          begin
            pPix^.R := 255;
            pPix^.G := 0;
            pPix^.B := 0;
          end;
          inc( pPix );
        end;
      8:
        for x := 0 to ImageEnView1.SelectionMask.Width - 1 do
        begin
          // 8 Bit mask (values are 0 to 255)
          if pSel^ <> 0 then
          begin
            pPix^.R := 255;
            pPix^.G := 0;
            pPix^.B := 0;
          end;
          inc( pSel );
          inc( pPix );
        end;
    end;
  end;
  ImageEnView1.Update();
end;

var
  x, y, x1, x2, y1, y2, pc: integer;
  polysel:ppointarray;
  SelMask:Tiemask;
  pSel: pbyte;
  pPix: PRGB;
begin
  with (ActiveMDIChild as TMDIChild) do
 begin
  if ImageEnView1.IEBitmap.PixelFormat <> ie24RGB then
    raise Exception.create( 'Not 24bit' );

  ImageEnView1.proc.GetReSel( x1, y1, x2, y2, polysel, pc, SelMask );

  if SelMask.IsEmpty then
    raise Exception.create( 'Nothing selected' );

  // Process selected area
  for y := 0 to SelMask.Height - 1 do
  begin
    pSel := SelMask.ScanLine[ y ];
    pPix := ImageEnView1.IEBitmap.ScanLine[ y ];

    case SelMask.BitsPerPixel of
      1:
        for x := 0 to SelMask.Width - 1 do
        begin
          // 1 Bit mask (values are 0 or 1)
          if (pbytearray(pSel)^[x shr 3] and iebitmask1[x and $7]) <> 0 then
          begin
            pPix^.R := 255;
            pPix^.G := 0;
            pPix^.B := 0;
          end;
          inc( pPix );
        end;
      8:
        for x := 0 to SelMask.Width - 1 do
        begin
          // 8 Bit mask (values are 0 to 255)
          if pSel^ <> 0 then
          begin
            pPix^.R := 255;
            pPix^.G := 0;
            pPix^.B := 0;
          end;
          inc( pSel );
          inc( pPix );
        end;
    end;
  end;
  ImageEnView1.Update();
end;