GH C# Component tips_寸法線を記述します（Rhino6版）

DrawDimensionsForRhino6GH.cs

using System;
using System.Collections;
using System.Collections.Generic;

using Rhino;
using Rhino.Geometry;

using Grasshopper;
using Grasshopper.Kernel;
using Grasshopper.Kernel.Data;
using Grasshopper.Kernel.Types;

using System.Drawing;
using Rhino.DocObjects;

/// <summary>
/// This class will be instantiated on demand by the Script component.
/// </summary>
public class Script_Instance : GH_ScriptInstance
{
#region Utility functions
  /// <summary>Print a String to the [Out] Parameter of the Script component.</summary>
  /// <param name="text">String to print.</param>
  private void Print(string text) { /* Implementation hidden. */ }
  /// <summary>Print a formatted String to the [Out] Parameter of the Script component.</summary>
  /// <param name="format">String format.</param>
  /// <param name="args">Formatting parameters.</param>
  private void Print(string format, params object[] args) { /* Implementation hidden. */ }
  /// <summary>Print useful information about an object instance to the [Out] Parameter of the Script component. </summary>
  /// <param name="obj">Object instance to parse.</param>
  private void Reflect(object obj) { /* Implementation hidden. */ }
  /// <summary>Print the signatures of all the overloads of a specific method to the [Out] Parameter of the Script component. </summary>
  /// <param name="obj">Object instance to parse.</param>
  private void Reflect(object obj, string method_name) { /* Implementation hidden. */ }
#endregion

#region Members
  /// <summary>Gets the current Rhino document.</summary>
  private readonly RhinoDoc RhinoDocument;
  /// <summary>Gets the Grasshopper document that owns this script.</summary>
  private readonly GH_Document GrasshopperDocument;
  /// <summary>Gets the Grasshopper script component that owns this script.</summary>
  private readonly IGH_Component Component;
  /// <summary>
  /// Gets the current iteration count. The first call to RunScript() is associated with Iteration==0.
  /// Any subsequent call within the same solution will increment the Iteration count.
  /// </summary>
  private readonly int Iteration;
#endregion

  /// <summary>
  /// This procedure contains the user code. Input parameters are provided as regular arguments,
  /// Output parameters as ref arguments. You don't have to assign output parameters,
  /// they will have a default value.
  /// </summary>
  private void RunScript(bool bake)
  {
    //Planeを適当に作成。
    Point3d plnPt1 = new Point3d(200, 400, 0);
    Point3d plnPt2 = new Point3d(900, 600, 0);
    Point3d plnPt3 = new Point3d(1200, 800, 0);
    Plane dimPlane = new Plane(plnPt1, plnPt2, plnPt3);

    //寸法の間隔を点でリストに追加。Point2dであることに注意。
    Point2d dimPt1 = new Point2d(0, -150);
    Point2d dimPt2 = new Point2d(1500, -150);

    //LinearDimensionオブジェクトを作成。
    LinearDimension lineDim =
      new LinearDimension(dimPlane, dimPt1, dimPt2, new Point2d(dimPt1.X, dimPt1.Y - 250));

    //寸法スタイルを設定する。
    lineDim.ParentDimensionStyle = this.FindDimStyleByName("dim_GH-Bake");

    //描画のためにひとつのデータでもリストに入れてから描画した方が無難。計算の回し方で問題を起こす場合があるので。
    this.lineDimList.Add(lineDim);

    //ボタンを押したらBakeする。
    if(bake)
    {
      //doc.Objects.AddLinearDimension(lineDim); でもOK。
      Rhino.RhinoDoc.ActiveDoc.Objects.AddLinearDimension(lineDim);
    }
  }

  // <Custom additional code> 
  //RunScriptの{}の外にデータを渡すために外で宣言する。
  public List<LinearDimension> lineDimList = new List<LinearDimension>();

  public DimensionStyle FindDimStyleByName(string dimStyleName)
  {
    DimensionStyle dimStyle = doc.DimStyles.FindName(dimStyleName);

    if(dimStyle == null)
    {
      //指定した名前のDimensionStyleがなかった場合は新規作成する。
      DimensionStyle newDimStyle = new DimensionStyle();

      //DimensionStyleのプロパティについては下記説明とほぼ同じ単語なので参照
      //https://docs.mcneel.com/rhino/6/help/es-es/documentproperties/dimensions_style.htm
      newDimStyle.LengthResolution = 1;
      newDimStyle.AngleResolution = 2;
      newDimStyle.TextHeight = 80;
      newDimStyle.TextGap = 20;
      newDimStyle.ExtensionLineExtension = 0;
      newDimStyle.ExtensionLineOffset = 10;
      newDimStyle.CentermarkSize = 30;
      newDimStyle.ArrowType1 = DimensionStyle.ArrowType.Dot;
      newDimStyle.ArrowType2 = DimensionStyle.ArrowType.Dot;
      newDimStyle.ArrowLength = 40;
      newDimStyle.LeaderArrowType = DimensionStyle.ArrowType.Dot;
      newDimStyle.LeaderArrowLength = 40;
      newDimStyle.TextVerticalAlignment = TextVerticalAlignment.Bottom;
      newDimStyle.TextHorizontalAlignment = TextHorizontalAlignment.Center;

      newDimStyle.Name = dimStyleName;
      newDimStyle.Index = doc.DimStyles.Add(newDimStyle, false);

      return newDimStyle;
    }
    else
    {
      //DimensionStyleに名前があった場合はそのStyleを返す。
      return dimStyle;
    }
  }

  public override void DrawViewportWires(IGH_PreviewArgs args)
  {
    foreach(LinearDimension item in lineDimList)
    {
      //Rhino6からDrawAnnotationで寸法が描画できる。
      args.Display.DrawAnnotation(item, Color.Red);
    }
  }

  public override BoundingBox ClippingBox
  {
    get
    {
      //GHファイル内に、このコンポーネント以外にオブジェクトがない場合はこのBoundingBoxを作っておく必要がある。
      return lineDimList[0].GetBoundingBox(Plane.WorldXY);;
    }
  }

  public override void BeforeRunScript()
  {
    //RunScriptの{}の外にリストを宣言、newした場合はこのメソッドの中でClear()しておく。
    lineDimList.Clear();
  }
  // </Custom additional code> 
}