WinAPI: SetPixel 和 SetPixelV - 设置设备环境中指定位置的颜色

//声明:
SetPixel(
  DC: HDC;        {设备环境句柄}
  X, Y: Integer;  {坐标}
  Color: COLORREF {颜色值}
): COLORREF;      {返回颜色值}

SetPixelV(
  DC: HDC;        {设备环境句柄}
  X, Y: Integer;  {坐标}
  Color: COLORREF {颜色值}
): BOOL;

{SetPixel 与 SetPixelV 功能一致, 但返回值不一样; 书上说 SetPixelV 更快.}


//举例:
procedure TForm1.FormPaint(Sender: TObject);
var
  c: TColor;
  x,y: Integer;
begin
  Self.Color := clWhite;
  c := clRed;
  x := 1;
  y := 1;

  while x < ClientWidth do
  begin
    while y < ClientHeight do
    begin
      SetPixel(Canvas.Handle, x, y, c);
      Inc(y,4);
    end;
    Inc(x,4);
    y := 0;
  end;
end;


//效果图:

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