I import a 2d DWG file that was exported from Revit.
I start working on it in 2D and get far into my work.
Suddenly my lines get ghost like and there are all kinds of weird planes and my boundaries are no longer accurate - a rectangle, for instance, might have 3 triangular “planes” inside it (meaning you click inside the rectangle and only part of the surface highlights) but no hidden lines or geometry are showing.
Sometime, but not always, I get a message that a 2d item I just pasted has “connected to hidden geometry” but no lines for geometry show, I definitely did not hide anything (I am positive), and even weirder if I paste somewhere else on the drawing and then use, for example, the left arrow key to force movement and then move to the exact area I just receiver the message there is no problem - there is no hidden geometry, it is something Sketchup has created.
So, 2 problems - objects becoming multi-plane and hidden geometries being created.
I am very careful to be working only in 2D and I don’t want to use Layout.
I am working in TOP view in Perspective (always).
If I switch to ISO I can see some lines are no longer on x,y,0
Weirder still, CTRL-Z does nothing, I cannot go back to the “correct” drawing I just had even if I undo 20 times.
Does anyone know what is happening… I’m about ready to abandon SketchUp and switch to Autocad/Revit.
The most probable thing that is happening that your model has something placed very far from the model origin point. This produces display artifacts like you describe. Perhaps the DWG you imported has, for instance, coordinates derived from a real world map coordinate system so that it origin might be located thousands of kilometers away.
Post the model to get a more accurate diagnosis than mere guesses.
How do you know? There is no 2D version of SketchUp, so any drawn line or edge can always be in 3D, keeping the camera in parallel projection from above does not guarantee 2D it just makes it so you cant see it, it does not lock in 2D.
This sounds like a misunderstanding of how tags work. Tags control visibility only, not object interaction. If you have raw geometry (edges, faces, etc) that has been assigned a tag, and you have that tag visibility set to “off”, you will not see those edges in your model space but they are still there and they are free to intersect, merge, and interact with any new geometry just the same as if they were visible. Turning off the tag visibility does not turn off the geometry. Only groups and components isolate geometry and prevent it from sticking to and interacting with other geometry. This is why best practice is to never tag raw geometry, leave all raw geometry untagged, make everything into a group or component and then add tags to the outside of each group or component. This workflow can be complicated by .dwg import process which can assign the Autocad “layers” as tags to the raw geometry. Best practice is to create components of assemblies and then use Clean Up or another extension to make sure all raw geometry is moved to “untagged”
This could be either intersecting with geometry that is hidden (raw geometry with a tag applied) or it could be your planes fracturing into 3d tessellations as you move because you are actually moving in 3D a small amount, or because you are dragging behind invisible geometry that is not moving on an invisible tag.
For a more comprehensive diagnosis please attach your .skp file to a reply so we can take a look and see whats going on.
People say things like this because they are frustrated, often from lack of information or incomplete knowledge. While not productive, this is human and understandable. I try to ignore those aspects of posts unless they are directly rude and to focus on being helpful if possible.
All of the above suggestions are very valid. I would just add that when you say you’ve imported from Revit, one of the things that typically happens in that scenario is that the Revit export creates groups within groups, and the Sketchup importer doesn’t disturb that. So you may think you are seeing all the geometry at one level, but actually there may be more geometry at a lower level that is tagged incorrectly (from Revit), and this just compounds your problem.
It is worth creating a new Sketchup model as a dwg import only and then explode out until you can really understand what Revit has done, and re-tag accordingly before re-grouping. Then you can import into the skp model you want to work with. And remember - naked geometry must always be untagged in SU!
