拉撒路（Lazarus）中有GetMouseMovePointsEx函数吗？

user1175743 发表于 Dev

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在另一个问题中，我问：在绘画盒上绘画-如何跟上鼠标的移动而没有延迟？。

该功能GetMouseMovePointsEx由Sebastian Z引起了我的注意，但是在拉撒路，我找不到此功能。

他提到在Delphi XE6中它在Winapi.Windows.pas，而在Lazarus中它不在Windows.pas。

我知道Lazarus绝不是Delphi的精确副本，但此功能听起来可能是我在其他问题中正在寻找的答案。我只是很难找到它的位置，甚至无法获得任何Delphi文档。我确实有Delphi XE，但目前尚未安装，我的项目是用Lazarus编写的。

我在Lazarus IDE中针对安装文件夹进行了“文件中查找...”搜索，唯一返回的结果是来自以下fpc来源之一：

lazarus \ fpc \ 2.6.4 \ source \ packages \ winunits-jedi \ src \ jwawinuser.pas

我不确定是否应该使用上述装置，或者Lazarus是否具有其他变体 GetMouseMovePointsEx?

使用Lazarus的人有经验GetMouseMovePointsEx吗？如果可以，我在哪里可以找到它？

谢谢。

塞巴斯蒂安·Z

这是一个使用Delphi的简单示例。您仍然需要做的是过滤掉已经收到的积分。

type
  TMouseMovePoints = array of TMouseMovePoint;
const
  GMMP_USE_HIGH_RESOLUTION_POINTS = 2;

function GetMouseMovePointsEx(cbSize: UINT; var lppt: TMouseMovePoint; var lpptBuf: TMouseMovePoint; nBufPoints: Integer; resolution: DWORD): Integer; stdcall; external 'user32.dll';

function GetMessagePosAsTPoint: TPoint;
type
  TMakePoints = packed record
    case Integer of
      1: (C : Cardinal);
      2: (X : SmallInt; Y : SmallInt);
  end;
var
  Tmp : TMakePoints;
begin
  Tmp.C := GetMessagePos;
  Result.X := Tmp.X;
  Result.Y := Tmp.Y;
end;

function GetMousePoints: TMouseMovePoints;
var
  nVirtualWidth: Integer;
  nVirtualHeight: Integer;
  nVirtualLeft: Integer;
  nVirtualTop: Integer;
  cpt: Integer;
  mp_in: MOUSEMOVEPOINT;
  mp_out: array[0..63] of MOUSEMOVEPOINT;
  mode: Integer;
  Pt: TPoint;
  I: Integer;
begin
  Pt := GetMessagePosAsTPoint;

  nVirtualWidth := GetSystemMetrics(SM_CXVIRTUALSCREEN) ;
  nVirtualHeight := GetSystemMetrics(SM_CYVIRTUALSCREEN) ;
  nVirtualLeft := GetSystemMetrics(SM_XVIRTUALSCREEN) ;
  nVirtualTop := GetSystemMetrics(SM_YVIRTUALSCREEN) ;
  cpt := 0 ;
  mode := GMMP_USE_DISPLAY_POINTS ;

  FillChar(mp_in, sizeof(mp_in), 0) ;
  mp_in.x := pt.x and $0000FFFF ;//Ensure that this number will pass through.
  mp_in.y := pt.y and $0000FFFF ;
  mp_in.time := GetMessageTime;
  cpt := GetMouseMovePointsEx(SizeOf(MOUSEMOVEPOINT), mp_in, mp_out[0], 64, mode) ;

  for I := 0 to cpt - 1 do
  begin
   case mode of
     GMMP_USE_DISPLAY_POINTS:
       begin
         if (mp_out[i].x > 32767) then
            mp_out[i].x := mp_out[i].x - 65536;
         if (mp_out[i].y > 32767) then
            mp_out[i].y := mp_out[i].y - 65536;
       end;
   GMMP_USE_HIGH_RESOLUTION_POINTS:
     begin
      mp_out[i].x := ((mp_out[i].x * (nVirtualWidth - 1)) - (nVirtualLeft * 65536)) div nVirtualWidth;
      mp_out[i].y := ((mp_out[i].y * (nVirtualHeight - 1)) - (nVirtualTop * 65536)) div nVirtualHeight;
     end;
   end;
  end;

  if cpt > 0 then
  begin
    SetLength(Result, cpt);
    for I := 0 to cpt - 1 do
    begin
      Result[I] := mp_out[I];
    end;
  end
  else
    SetLength(Result, 0);
end;

// the following is for demonstration purposes only, it still needs some improvements like filtering out points that were already processed. But it's good enough for painting a blue line on a TImage
procedure TForm1.Image1MouseMove(Sender: TObject; Shift: TShiftState; X,
  Y: Integer);
var
  MMPoints: TMouseMovePoints;
  Pt: TPoint;
  I: Integer;
begin
  Image1.Canvas.Pen.Color := clBlue;
  MMPoints := GetMousePoints;

  for I := 0 to Length(MMPoints) - 1 do
  begin
    Pt.x := MMPoints[I].x;
    Pt.y := MMPoints[I].y;
    Pt := Image1.ScreenToClient(Pt);
    if I = 0 then
      Image1.Canvas.MoveTo(PT.X, pt.y)
    else
      Image1.Canvas.LineTo(PT.X, pt.y);
  end;
end;