开源DeepGantt智慧项目管理工作进度计划软件的绘制折线虚线函数Delphi源代码

DeepGantt智慧项目管理工作进度计划软件是一款DeepSeek AI驱动的新一代智慧项目管理工作进度计划软件，既可以用于工程企业的大型项目进度管理，也适用于个人的工作时间管理。该软件采用付费开源的方式与客户共享源代码，DeepGantt使用最新版的Delphi 12社区版开发，源代码同时兼容即将发布的Delphi 13 佛罗伦萨 版本。 

DeepGantt可以通过可视化方式绘制甘特图（横道图），也可以生成双代号网络图，其中双代号网络图中会用到绘制折线虚线的功能，如下如所示：

现将DeepGantt中绘制折线虚线的Delphi源码共享出来以回馈Delphi社区，源码如下：

procedure DrawDashedLineAllPoint(Canvas: TCanvas; const Points: array of TPoint; DashLength: Integer = 5; GapLength: Integer = 5);
var
  I: Integer;
  StartPoint, EndPoint: TPoint;
  IsVertical, IsHorizontal: Boolean;

  // 专用垂直虚线绘制
  procedure DrawVerticalDashed(X, Y1, Y2: Integer);
  var
    CurrentY: Integer;
    IsDash: Boolean;
  begin
    CurrentY := Y1;
    IsDash := True;
    while CurrentY < Y2 do
    begin
      if IsDash then
      begin
        Canvas.MoveTo(X, CurrentY);
        Canvas.LineTo(X, Min(CurrentY + DashLength, Y2));
      end;
      Inc(CurrentY, IfThen(IsDash, DashLength, GapLength));
      IsDash := not IsDash;
    end;
  end;

  // 专用水平虚线绘制
  procedure DrawHorizontalDashed(Y, X1, X2: Integer);
  var
    CurrentX: Integer;
    IsDash: Boolean;
  begin
    CurrentX := X1;
    IsDash := True;
    while CurrentX < X2 do
    begin
      if IsDash then
      begin
        Canvas.MoveTo(CurrentX, Y);
        Canvas.LineTo(Min(CurrentX + DashLength, X2), Y);
      end;
      Inc(CurrentX, IfThen(IsDash, DashLength, GapLength));
      IsDash := not IsDash;
    end;
  end;

  // 通用斜线绘制
  procedure DrawDiagonalDashed;
  var
    Distance, Remaining: Double;
    DeltaX, DeltaY: Double;
    CurrentX, CurrentY: Integer;
    IsDash: Boolean;
  begin
    Distance := Sqrt(Sqr(EndPoint.X - StartPoint.X) + Sqr(EndPoint.Y - StartPoint.Y));
    if Distance = 0 then Exit;

    DeltaX := (EndPoint.X - StartPoint.X) / Distance;
    DeltaY := (EndPoint.Y - StartPoint.Y) / Distance;

    CurrentX := StartPoint.X;
    CurrentY := StartPoint.Y;
    IsDash := True;
    Remaining := Distance;

    while Remaining > 0 do
    begin
      if IsDash then
      begin
        Canvas.MoveTo(CurrentX, CurrentY);
        Canvas.LineTo(
          CurrentX + Round(DashLength * DeltaX),
          CurrentY + Round(DashLength * DeltaY)
        );
      end;

      // 整数步长更新
      if IsDash then
      begin
        Inc(CurrentX, Round(DashLength * DeltaX));
        Inc(CurrentY, Round(DashLength * DeltaY));
        Remaining := Remaining - DashLength;
      end
      else
      begin
        Inc(CurrentX, Round(GapLength * DeltaX));
        Inc(CurrentY, Round(GapLength * DeltaY));
        Remaining := Remaining - GapLength;
      end;

      IsDash := not IsDash;
    end;
  end;

begin
  for I := 0 to High(Points) - 1 do
  begin
    StartPoint := Points[I];
    EndPoint := Points[I + 1];

    // 确定线型类别
    IsVertical := (StartPoint.X = EndPoint.X);
    IsHorizontal := (StartPoint.Y = EndPoint.Y);

    // 分类处理
    if IsVertical then
    begin
      if StartPoint.Y < EndPoint.Y then
        DrawVerticalDashed(StartPoint.X, StartPoint.Y, EndPoint.Y)
      else
        DrawVerticalDashed(StartPoint.X, EndPoint.Y, StartPoint.Y);
    end
    else if IsHorizontal then
    begin
      if StartPoint.X < EndPoint.X then
        DrawHorizontalDashed(StartPoint.Y, StartPoint.X, EndPoint.X)
      else
        DrawHorizontalDashed(StartPoint.Y, EndPoint.X, StartPoint.X);
    end
    else
    begin
      DrawDiagonalDashed;
    end;
  end;
end;