[Alexandr_17_10]

Код:

procedure MergePNGLayer(Layer1,Layer2: TPNG; Const aLeft,aTop:Integer);
var
  x, y: Integer;
  SL1,  SL2,  SLBlended : pRGBLine;
  aSL1, aSL2, aSLBlended: PByteArray;
  blendCoeff: single;
  blendedPNG, Lay2buff: TPNG;
begin
  blendedPNG:=TPNG.Create;
  blendedPNG.Assign(Layer1);
  Lay2buff:=TPNG.Create;
  Lay2buff.Assign(Layer2);
  //SetPNGCanvasSize(Layer2,Layer1.Width,Layer1.Height,aLeft,aTop);
  for y := 0 to Layer1.Height-1 do
  begin
    SL1 := Layer1.Scanline[y];
    SL2 := Layer2.Scanline[y];
    aSL1 := Layer1.AlphaScanline[y];
    aSL2 := Layer2.AlphaScanline[y];
    SLBlended := blendedPNG.Scanline[y];
    aSLBlended := blendedPNG.AlphaScanline[y];
    for x := 0 to Layer1.Width-1 do
    begin
      blendCoeff:=aSL1[x] * 100/255/100;
      aSLBlended[x] := round(aSL2[x] + (aSL1[x]-aSL2[x]) * blendCoeff);
      SLBlended[x].rgbtRed   := round(SL2[x].rgbtRed + (SL1[x].rgbtRed-SL2[x].rgbtRed) * blendCoeff);
      SLBlended[x].rgbtGreen := round(SL2[x].rgbtGreen + (SL1[x].rgbtGreen-SL2[x].rgbtGreen) * blendCoeff);
      SLBlended[x].rgbtBlue  := round(SL2[x].rgbtBlue + (SL1[x].rgbtBlue-SL2[x].rgbtBlue) * blendCoeff);
    end;
  end;
  Layer1.Assign(blendedPNG);
  Layer2.Assign(Lay2buff);
  blendedPNG.Free;
  Lay2buff.Free;
end;

Вызов

Код:

procedure TfrmRCE.RePayntImgMapDoms(IndexDoms, IndexRegion:Integer);
begin
  lblDisplayRegions0.Refresh;
  MergePNGLayer(MaskPngRegions, PngRegions[IndexDoms, IndexRegion], 0, 0);
  lblDisplayRegions0.Picture.Assign(MaskPngRegions);
end;

Отрисовывает только MaskPngRegions почемута