AUTOCAD import woes - any architects out there?
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Hey everybody, Im having problems when importing my cad base into sketchup7. I think it could possibly have to do with the survey was created in some other program that civil engineers use alot like land cad. I followed all basic import preparation rules like simplifying, cleaning and purging, and saving as 2004 dwg. The problem is that when I view the lines in SU, they "dance around" and move erratically - not letting me pick endpoints with the line tool and other issues. Some of the cad lines come out correct and behave, allowing for the typical delete short lines/make-faces process that you usually use in an imported dwg. Also, the topo lines look like they were splines or something; I can make faces no problem, but there is alot of "shining" (the white lines and noise that shows on the faces with no explaination) The only explaination is that SU is trying to triangulate way to many faces in too small of an area. I included the model and a jpg of the shining problem. Any help will be greatly appreciated!!!
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Is it placed in real world coordinates? SU doesn't handle very large co-ordinates that well. Place everything near origin before importing. Same goes for blocks. Some times you end up with only a few blocks that jitter, then it's the block's internal origin that's way off.
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In AutoCAD type 'base' and set it to 0,0,0.
When you import the DWG file do NOT keep the origin... -
When I import a drawing like this to draw contours I prefer just importing the image and tracing much simpler contour lines over the drawing. When you import a CAD drawing like that you end up (as you see) with Thousands of tiny little lines. i have to go in aand PEdit the lines and all of that --it;s just to hard. there is a simplify contours ruby floating around out there. but I just like using the freehand tool or other tools on top of the jpeg and draw my own contours. much easier.
Just a suggestion
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@unknownuser said:
When I import a drawing like this to draw contours I prefer just importing the image and tracing much simpler contour lines over the drawing. When you import a CAD drawing like that you end up (as you see) with Thousands of tiny little lines. i have to go in aand PEdit the lines and all of that --it;s just to hard. there is a simplify contours ruby floating around out there. but I just like using the freehand tool or other tools on top of the jpeg and draw my own contours. much easier.
Just a suggestion
You won't be able to trace jittering CAD imports. You wouldn't know where the lines should snap because what you see isn't what you get.
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@thomthom said:
Is it placed in real world coordinates? SU doesn't handle very large co-ordinates that well. Place everything near origin before importing. Same goes for blocks. Some times you end up with only a few blocks that jitter, then it's the block's internal origin that's way off.
Thank you thomthom - after spending all morning in the office figuering out what could be wrong, I simply moved the orgin (both manually in SU or in CAD pre-imported)and the jitter went away. You see, the problem is, I need to keep the coordinates in order to produce a seamless workflow between CAD (and all the xrefs from civil, architects, ect...) and LandFX. I can't just simply move my drawing to 0,0 - then everytime I get a dwg from the many others we work with it is a pain in the butt to align them up with my "new" coordinate. What Im really getting at is; I use a CAD plug in called Land FX that uses blocks to manage my planting plans. I link the active planting plan dwg file to a SU base that I already created the topo, place buildings, ect, and make sure the coordinates match the dwg. The blocks are then linked to components in the SU model, each plant block corresponding to a component plant. The link automattically uses the coordinates and a "grow" ruby (the opposite of drop) to place the components on my landform tin. Each file automatically updates eachother; ie. if I move a tree around in SU then save, when I open CAD that tree will be in its new place at the flattened elevation that I work in there. So thomthom, how far away from 0,0 in SU do things start messing up? If I uncheck preserve origin does it bring separate files that are on a coordinate in at the same place reletive to 0,0? Or does it pick a point on the dwg in the furthest 0,0 quadrant and just stick it there? Once again, thanks - its good to talk to someone who knows there stuff!
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@unknownuser said:
I see a huge amount of lines describing very little. I would have to agree that importing a 2d and tracing would get you off the ground quickly and allow for more effective construction on the surface. If you try to throw that single contour around while you are adding detail your work-flow will be slowed to a crawl.
thats because the contours were a spline from the civil engineers software, I know that you should simplify the heck out them, but I thought the spline might have had to do with the original problem!
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hmm... I see. Which plugin is it?
I'm wondering if it could be modified to take the Location information from SU into account when it syncs the files. So that you have your SU model at SUs origin.Not sure how far away the trouble starts.
At my office I often get models at their real world location. But I always copy what I need to import into a new DWG and pick one point in the drawaing as a reference point which I move to origin. That way, provided I use the same reference point, if I need to reimport the file it'll positioned the same as last.
But since you use that ruby, it complicates things. But there is no getting away with SU not being able to deal with numbers like AutoCAD. I can't do too large numbers, and it can't do too small. I do believe the ideal would be to position the SU model correctly using the Location setting in the Model window. And then have the ruby take that into account.
AutoCAD -> Revit workflow is kind of like that. In Revit you model around the origin and define in the project settings what real world coordinate the origin represent. -
You can try an easy trick: select all in your model and make a component (hopefully there are no unnecessary,stray lines miles away). Now the component will have its own axes - as close to the component geometry as possible (i.e. at the corner of the bounding box).
Now export this component as a SU model (right click > save as), open it, work on it and all and if you need the original placement, go back to the original model, right click again and reload. You can even explode the component now if you wish.
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@gaieus said:
You can try an easy trick: select all in your model and make a component (hopefully there are no unnecessary,stray lines miles away). Now the component will have its own axes - as close to the component geometry as possible (i.e. at the corner of the bounding box).
Now export this component as a SU model (right click > save as), open it, work on it and all and if you need the original placement, go back to the original model, right click again and reload. You can even explode the component now if you wish.
hmmm.. that sounds like a neat trick. Does that mean all the coordinate data will be reletive to the component axis and the only million feet away coordinate would be the one defining the location of the component? Ill keep you posted next time I get a chance to try it out. My only concern is how and if LandFX will be able to read the relationship to convert back to CAD.
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If you explode the re-imported (reloaded) component in the original but otherwise useless model, it will work as if you'd modelled everything in place there.
Your imported component will still be in the model file though but you can easily get rid of it by purging.
I do this (in a much smaller scale however - city block vs. individual buildings) but have done it successfully with a whole (Medieval) town and its churches. You can see some shots here. The extent of the model is about 1.3 kilometres / 0.8 miles so there was no such problem however I had performance issues.
As for modelling and geolocating, it can be used for GE quite efficiently although you always need to keep in mind that GE is a spherical projection and SU is orthographical so after a while this will cause conflicts.
Try it out with a simple, not crucial model first.
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