Rudi @Revitalizer Honke
shared two important hints: a performance issue using ElementTransformUtils and a problem reporting mechanism built into the TessellatedShapeBuilderResult method GetIssuesForFaceSet.
First, though, let's highlight an even more important upcoming event, the series of DevDays online webinars:
- Register now for Autodesk DevDays online webinars
- Avoid using
ElementTransformUtilsfor batches - Finding cause of
DirectShapegeneration problem
Register now for Autodesk DevDays Online Webinars
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Avoid Using ElementTransformUtils for Batches
The ElementTransformUtils MoveElement method has an important performance issue when used on a large number of elements, as pointed out by Revitalizer in
the Revit API discussion forum thread
on a batch method for placing adaptive component points:
Question: I have a performance issue placing and moving adaptive components using the following code:
# place family instance, get default placement points,
# subtract from my desired coordinates (list) and move element
inst = AdaptiveComponentInstanceUtils.CreateAdaptiveComponentInstance(
doc, inst)
placePointIds = []
placePointIds = AdaptiveComponentInstanceUtils.GetInstancePlacementPointElementRefIds(
inst)
for ind, item in enumerate(placePointIds):
# assign a point object to refpt
# refpt is the orginal point of the family
# newpt the new point derived from pt information
refpt = doc.GetElement(item)
newpt = pt[ind]
trans = newpt.Subtract(refpt.Position)
ElementTransformUtils.MoveElement(doc, item, trans)
Answer: There is a performance problem with ElementTransformUtils, as pointed out in the thread
on ElementTransformUtils: performance issue.
It seems to auto regenerate after each movement.
In that case, you have to move every point separately. If the bad performance issue is related to the ElementTransformUtils methods, this might give better performance. To know for sure, you'd have to test.
Maybe you can use SetCoordinateSystem instead:
(refpt as ReferencePoint).SetCoordinateSystem()
Fleshed out a bit more, it could look like this:
Element refpt = doc.GetElement(item); XYZ newpt = pt[ind]; Transform tf = Transform.Identity; tf.Origin = newpt; (refpt as ReferencePoint).SetCoordinateSystem(tf);
Response: Hey, awesome!!! It works! Performance is way better and the code runs fluid!
I suppose this is even better than moving components, although I would be interested to compare both methods once it is fixed.
My code now looks like this:
placePointIds = AdaptiveComponentInstanceUtils.GetInstancePlacementPointElementRefIds(
inst):
for ind, item in enumerate(placePointIds):
refpt = doc.GetElement(item)
newpt = pt[ind]
tf = Transform.Identity
tf.Origin = newpt
refpt.SetCoordinateSystem(tf);
Finding Cause of DirectShape Generation Problem
Revitalizer provided more important hints on detecting problems in
the Revit API discussion forum thread
on a problem with solid creation by TessellatedShapeBuilder:
Question: I want to import some solids created by an external library into Revit with TessellatedShapeBuilder.
All solids are correctly tessellated and closed.
But I got sometimes the following error on calling TessellatedShapeBuilder.Build:
Could not create consistent vertex list
As far as I know there are some restriction about triangles, e.g., the distance between two vertices.
I could merge two vertices in this case.
But I don't know any other restriction, and how could I adjust my vertex list and triangle list to avoid the above error?
Answer:
The problem might indeed be due to vertices lying too close together; they need to be at least about 2 mm apart.
What I always do in these kind of cases:
While reading the input vertices one by one, I put them into a dictionary equipped with an XYZ comparison operator.
If a new vertex is very close to an existing one, my comparison operator considers the two vertices to be equal, so I ignore it and use the existing one instead.
The GetVertices method
in The Building Coder samples CmdNestedInstanceGeo.cs does
something similar using an XyzEqualityComparer.
You would simply have to replace the face vertex index of any ignored vertex by the index of its replacement.
There is also an Appliation.MinimumThickness property.
It says in
the Revit API help file RevitAPI.chm:
The minimum thickness allowed in Revit for a variety of geometric constructs. These include blends, extrusions, and wall layers.
Whatever problem you run into, try reproducing the same issue manually through the user interface.
That will probably provide more information on what the problem is than the Revit API does.
You should also have a look at TessellatedShapeBuilderResult.GetIssuesForFaceSet.
In fact, it may localize exactly the faces and vertices causing the problem.
Each TesselatedBuildIssue provides a GetDescription method.
Addendum
Rudi disagrees with my statement in the introduction above and corrects it, saying:
Thank you for mentioning me in the current TBC post!
I must admit that for both topics (ElementTransformUtils and DirectShape), I could not help the people, in fact:
- For the ElementTransformUtils method, FAIR59 provided the solution (SetCoordinateSystem), but he isn't even mentioned on TBC.
- For the DirectShape problem, the user said that he already checked my suggestions, without any success.
I still think Rudi's suggestions are helpful and important and worth highlighting.
Many thanks to FAIR59 as well, of course, as so often before in the past couple of months.
