Can't intersect lines on a plane
-
Hi there,
This is driving me potty - when importing a .dwg to Sketchup Pro I'm not able to intersect the lines with a flat plan or close various faces by adding a line etc. The lines remain slightly thicker in places to denote a non bounded shape and I can't do anything with the model without redrawing, which defeats the entire point of importing the drawing file from CAD.
See attached image, you can see that certain shapes which are bounded on all sides are still selecting as part of a whole, meaning I can't simply extrude walls etc up.
Is this a bug? Is there a way around this?
I should point out that my .dwg data has been flattened to 2d in AutoCAD.
I've tried the 'flatten' plugin, which doesn;t make any difference.
Any help appreciated,
Thanks,
-
Keep in mind that SketchUp's Intersect operation does exactly what it says; Intersect Faces.
It's possible that you have gaps in the lines of your DWG file which will cause you problems with getting separation between regions. There are a few obvious ones in the image you posted.
-
Hi bosseye,
Check the imported PLan with the plugin "Stray Lines". This has often helped me. Sometimes you see these gaps only when extremely enlarged.
http://www.smustard.com/script/StrayLines
Charly
-
Gentlemen, thank you for your prompt replies.
Charly, I've run the StrayLines plugin, along with the MakeFaces plugin by the same author and I'm surprised by how many tiny little errors it showed up in the model - essentially it labels those areas which if I correct, suddenly I can bound faces and then push/pull as required. So thanks, this plugin (although not the instantaneous workflow I was imagining with .dwg import) has saved the day.
It is curious though - I'm religious with my snap settings in AutoCAD, I don't leave stray lines and I always ensure my lines are co-planar, so these myriad errors in the imported Sketchup data is odd because the errors are not there in the original CAD file.
-
ThomThom's EdgeTools help heal intersections too. I'd separate different types of lines and separate anything you don't really need to model/extrude (separate by groups (blocks)). I see in your test there are beam lines and doors--things that you don't need to make faces from for the wall model. You can extrude them separately, or draw over--but usually doors will be components and not extruded one by one. Just need a place holder in plan to remind you where those things are. The stairs as shown will not be useful for extrusion. It's a waste of time to make faces there unless you clean them up before import.
I do that: work on the plan BEFORE import to get clean basic shapes to extrude. Or I don't extrude at all. I import the plan as is and draw rectangles to outside walls, take it from there in SU. But that's just me.
It is nature of the beast to have problems with this whatever you do. I've rarely seen it make faces trouble-free.
-
Thanks for the reply - I'll try Thomthoms edge tool and see if that helps.
I'm having problems to be honest. I bought the pro version purely to be able to import .dwg data on the assumption that it would be quicker workflow, but it would appear that Sketchup is introducing errors on the import. Even really simple overlapped shapes drawn in CAD that are 100% snapped correctly, 100% flat still don't intersect correctly and make faces in Sketchup. Running the stray lines tool shows up myriad areas where lines suddenly don't join properly - these errors simply aren't in the original CAD file, so the only assumption is that Sketchup is not particularly good at importing the data.
A shame.
-
Sorry. It has problems, but for me it's worthwhile and I find most intersections that are square work. Circles and curves will definitely be messed up because as they change to segments, the intersecting lines do not meet the same way. I don't always use the CAD import directly but it's really helpful for layouts. Also it's the only way I know to bring topo lines in, which generally CAN be used with the plugins to make terrains, not to mention importing other extensive site info (or 3d) which would be really hard without dwg import.
-
@bosseye said:
.......to be able to import .dwg data on the assumption that it would be quicker workflow, but it would appear that Sketchup is introducing errors on the import. Even really simple overlapped shapes drawn in CAD that are 100% snapped correctly, 100% flat still don't intersect correctly and make faces in Sketchup......
Could you share what's in the model in your first post as DWG? instead of just the image?
-
Use vertex tools and make planar all lines.
-
@smicha said:
Use vertex tools and make planar all lines.
You mean adjust the individual vertexes on every line? I'll see if I can find the vertex tools plugin, its one of ThomThom's isn't if? I assume there is a command to make all vertexes co-planar as oppose to having to individually select....
Frankly, I'm coming to the conclusion that importing .dwg information into Sketchup is broken, or at the very least pretty buggy. I made another really simple .dwg file to test, just some circles and polylines. All 100% flat, all co-planar etc etc. I tried with all as polylines, I tried breaking lines up into individual segments, I tried various flattening commands (all data is reporting a z value of 0).
Import into Sketchup and after running all the intersect with model commands ultimately I'm left with this:
All the selected faces select with one click. They're not grouped, stray lines tool reports no stray lines so there isn't any gaps meaning they're joined up - its bizarre and frankly not good. And this is with an utterly simply CAD plan.
And apologies, I can't upload any CAD data due to client copyright issues. If you have the software to open a CAD file I might upload though, you can draw some circles and lines and import that to Sketchup and see if you can recreate the issue yourself.
-
Importing dwg works like a charm on my machine
- I created some shapes - 3ds max. Exported them as autocad 2004 dwg file.
- Imported in SU 2013.
- Triple click on any line to select it.
- Right click - generate faces.
That's it.
PS. Yes - Vertex Tools is a TomTom's plugin (one of many that I cannot image working without).
-
I go back and forth between AutoCAD and SketchUp all the time with no problems.
Some suggestions:
The cleaner your AutoCAD file the better it will open in SketchUp.
I keep a AutoCAD file called To SketchUp that has essentially nothing in it (no blocks, no linetypes, meta data, etc.). I copy my geometry into that file then use Purge (extensively)and Overkill to get the file ready for SketchUp.
SketchUp doesn't have arcs or circles so any line that intersects a circle will give you trouble. On the SketchUp side open the Entity Info panel and increase the chord count of the arcs to give you smoother lines. On the AutoCAD side I always extend any lines that intersect arcs several inches beyond the arc so I can trim them back in SketchUp.
I hope something here helps.
Advertisement