AEC DevBlog

How to programmatically load a new symbol from an existing Family in a Revit project

By Gopinath Taget

You will find that neither of the following overloaded methods will work for you:

public bool Document::LoadFamilySymbol(string filename, string name)

public bool Document::LoadFamilySymbol(string filename, string name, out FamilySymbol symbol)

You will have to use the third version of this overloaded method:

public bool Document::LoadFamilySymbol(string filename, string name, IFamilyLoadOptions familyLoadOptions, out FamilySymbol symbol)

In order to use this though, you will have to implement the IFamilyLoadOptions interface like this:

class FamilyOption : IFamilyLoadOptions

{

    public bool OnFamilyFound(

        bool familyInUse,

        out bool overwriteParameterValues)

    {

        overwriteParameterValues = true;

        return true;

    }

 

    public bool OnSharedFamilyFound(

        Family sharedFamily,

        bool familyInUse,

        out FamilySource source,

        out bool overwriteParameterValues)

    {

        source = FamilySource.Family;

        overwriteParameterValues = true;

        return true;

    }

}

 
Next use the instance of this class with the right version of the LoadFamilySymbol method like this:

document.LoadFamilySymbol(familyFile, symbolName, new FamilyOption(), out gotSymbol)

Invisible Reference

By Mikako Harada

Issue

I created a family which consists of a solid and a void. I inserted it to another family. As a simple example, it looks like a picture below; I placed two instances of the family, one vertically and the other horizontally.

When I try to align their edges using UI, I can select a "imaginary" line like shown in blue below. How can get this line using API?  When I iterate through the geometry of family instance, I only see the solid.   

Solution

Element Geometry option has a setting, IncludeNonVisibleObjects.  When it is true, it includes element geometry which is not visible. The default is false. Below shows a sample usage:     

         Options geomOp = m_app.Create.NewGeometryOptions();

         geomOp.ComputeReferences = true;

         geomOp.IncludeNonVisibleObjects = true;

         geomElem = elem.get_Geometry(geomOp);

 

Faces/Edges returned from Element.Geometry have no reference

By Mikako Harada

Issue

I'm trying to align two elements. NewAlignment() method requires references as arguments. But faces/edges returned from Element.Geometry has no reference. It simply returns null. How can I obtain references from a given element?

Solution

If you need to access valid reference objects from the give geometry, you will need to set CalculateReferences property of geometry option to true before you call Geometry. By default, it is set to false for performance reason: e.g.,

    Options geomOp = m_app.Create.NewGeometryOptions();

    geomOp.ComputeReferences = true;

Getting Started with Revit 2014 API and Family Guide

By Mikako Harada

Last year, I wrote about my handy "Getting Started with Revit API" document (sometime I called it "phase zero") as I get inquiries about Revit API every so often. Here it is the updated version:  Download Getting Started with Revit 2014 API. The changes are very minor: version number update and pointing to newer recordings. Old recordings may be still valuable for learning basics as the newer ones tend to focus on more advanced and specific topics. So I'm not going to repeat it here; rather I refer to the last year's page for the majority of part.

Another inquiry I received recently is about learning materials about Family creation. I double-checked the content manager here and he confirms that the Family Guide posted here is still the most complete one you can refer to (although it was not updated for a few years.)  This page include guides translated in various languages, such as Chinese, German, French, and Japanese. If you are new to Revit, this will be a good starting point to learn Family creation. If you are coming from Programing background, I must also emphasize that to master Revit API, you will need to understand how Revit works in UI.

Good luck!

Capture Escape key on Revit

By Augusto Goncalves

In some cases we need to hook to Revit to track some keys, for instance the ESCAPE key. This can be done with Win32 APIs with SetWindowsHookEx method. Below is the regular OnStartup and OnShutdown with calls to it.

public Result OnStartup(UIControlledApplication application)

{

  // hook

  HookMainApp();

  return Result.Succeeded;

} 

public Result OnShutdown(UIControlledApplication application)

{

  // unhook

  UnhookMainApp();

  return Result.Succeeded;

} 

private void KeyPressed(Keys keyPressed)

{

  if (keyPressed == Keys.Escape)

  {

    TaskDialog.Show("Key was pressed", "Escape");

  }

} 

And to make this work, also include the following methods on the project:

#region "Windows Hook"

// **********

// Code based on the following post

// http://www.pinvoke.net/default.aspx/user32.setwindowshookex

// **********

 

private void HookMainApp()

{

  // initialize our delegate

  this.myCallbackDelegate = new HookProc(this.MyCallbackFunction);

 

  // get the process and set up the hook

  using (Process process = Process.GetCurrentProcess())

  using (ProcessModule module = process.MainModule)

  {

    hookId = SetWindowsHookEx(HookType.WH_KEYBOARD,

      this.myCallbackDelegate, IntPtr.Zero,

      (uint)AppDomain.GetCurrentThreadId());

  }

}

 

private void UnhookMainApp()

{

  UnhookWindowsHookEx(hookId);

}

 

private int MyCallbackFunction(int code,

  IntPtr wParam, IntPtr lParam)

{

  if (code < 0)

  {

    //you need to call CallNextHookEx without

    // further processing and return the value

    // returned by CallNextHookEx

    return CallNextHookEx(IntPtr.Zero, code,

      wParam, lParam);

  }

 

  // we can convert the 2nd parameter (the key code)

  // to a System.Windows.Forms.Keys enum constant

  Keys keyPressed = (Keys)wParam.ToInt32();

  KeyPressed(keyPressed);

 

  //return the value returned by CallNextHookEx

  return CallNextHookEx(IntPtr.Zero, code,

    wParam, lParam);

}

 

// hook deleate

private HookProc myCallbackDelegate = null;

 

// hook id for unhook

IntPtr hookId;

 

[DllImport("user32.dll")]

static extern int CallNextHookEx(IntPtr hhk, int nCode,

  IntPtr wParam, IntPtr lParam);

 

[DllImport("kernel32.dll")]

static extern uint GetCurrentThreadId();

 

[DllImport("user32.dll", SetLastError = true)]

[return: MarshalAs(UnmanagedType.Bool)]

static extern bool UnhookWindowsHookEx(IntPtr hhk);

 

[DllImport("user32.dll", SetLastError = true)]

static extern IntPtr SetWindowsHookEx(

  HookType hookType, HookProc lpfn, IntPtr hMod,

  uint dwThreadId);

 

public enum HookType : int

{

  WH_JOURNALRECORD = 0,

  WH_JOURNALPLAYBACK = 1,

  WH_KEYBOARD = 2,

  WH_GETMESSAGE = 3,

  WH_CALLWNDPROC = 4,

  WH_CBT = 5,

  WH_SYSMSGFILTER = 6,

  WH_MOUSE = 7,

  WH_HARDWARE = 8,

  WH_DEBUG = 9,

  WH_SHELL = 10,

  WH_FOREGROUNDIDLE = 11,

  WH_CALLWNDPROCRET = 12,

  WH_KEYBOARD_LL = 13,

  WH_MOUSE_LL = 14

}

 

delegate int HookProc(int code, IntPtr wParam,

  IntPtr lParam);

 

#endregion

Navisworks 2014 API new feature - ToolPlugin

By Xiaodong Liang

ToolPlugin is actually a combination of InputPlugin and RenderPlugin. It allows you to customize the tool. Typically, it configures the behavior when mouse clicking the object. So you could switch between the native tool of Navisworks and your tools.

Firstly, create a class deriving from ToolPlugin . It is a kind of implicit plugin which has no interface. So the attribute DisplayName could be ignored. Next, override the methods you want to use. e.g. the following code demo overrides MouseDown and OverlayRenderModel. When the mouse clicks, it records the selected object, next draws a custom graphics with the bounding box of the object. In another word, when the mouse clicks the object, it will not highlight the object anymore, it will draw a temporary cuboids.

// The ToolPlugin example.

[Plugin("ToolPluginTest", "ADSK")]

public class ToolPluginTest : ToolPlugin

{

    ModelItem clickedModel = null;

 

    public override bool MouseDown(View view,

                        KeyModifiers modifiers,

                        ushort button,

                        int x,

                        int y,

                        double timeOffset)

    {

        // get current selection
        PickItemResult itemResult =

            view.PickItemFromPoint(x, y);

        if (itemResult != null)

        {

            clickedModel =

                itemResult.ModelItem;

            Application.ActiveDocument.ActiveView.

                           RequestDelayedRedraw(ViewRedrawRequests.Render);

        }

        return false;

    }

 

    public override void OverlayRenderModel(View view, Graphics graphics)

    {

        if (clickedModel != null)

        {

            //color for graphics

            Color yellow = Color.FromByteRGB(255, 255, 0);

            graphics.Color(yellow, 0.8);

 

            //boundingbox of the current selection

            BoundingBox3D boundingBox = clickedModel.BoundingBox();

 

            Point3D origin = boundingBox.Min;

            Vector3D xVector =

                new Vector3D((boundingBox.Max -

                                boundingBox.Min).X, 0, 0);

            Vector3D yVector =

                new Vector3D(0, (boundingBox.Max -

                                boundingBox.Min).Y, 0);

            Vector3D zVector =

                new Vector3D(0, 0, (boundingBox.Max -

                                boundingBox.Min).Z);

 

            //draw a cuboid

            graphics.Cuboid(origin, xVector, yVector, zVector, true);

        }

    }

}

 

To let Navisworks know to use your tool, you will need to write some codes in your main workflow (e.g. main plugin). Find your tool plugin, and set it as a current tool by

Tool.SetCustomToolPlugin

To switch back to the native tool of Navisworks, you could just set the tool to any mode of navigation.

[Plugin("EnableToolPluginExample", "ADSK",
         DisplayName = "EnableToolPlugin")]

public class EnableToolPluginExample : AddInPlugin

{

    static bool enable = false;

    public override int Execute(params string[] parameters)

    {

        if (enable)

        {                

            //switch to the native tool
            Application.MainDocument.Tool.Value = Tool.Select;        

        }

        else

        {

            //switch to custom tool

            ToolPluginRecord toolPluginRecord =

                (ToolPluginRecord)Application.Plugins.FindPlugin(

                                                 "ToolPluginTest.ADSK");

            Application.MainDocument.Tool.

                SetCustomToolPlugin(toolPluginRecord.LoadPlugin());

        }

        enable = !enable;

        return 0;

    }

}