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Cad file size or points limit

#1

Hi there,
I was wondering if you can help with my query, I tried to upload contour from dwg file and got a message that there are too many points and suggestion box to reduce the tolerance. I couldn't find help on this topic to best approach this ie I tried to delete some of the contour lines that are not needed and purge the dwg file to reduce the size but still getting the too many points and the process will be slow message. And with reduction method not sure how much is it optimal size without losing too much tolerance.
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#2

(12-04-2019, 08:49 AM)Mick Wrote: Hi there,
I was wondering if you can help with my query, I tried to upload contour from dwg file and got a message that there are too many points and suggestion box to reduce the tolerance. I couldn't find help on this topic to best approach this ie I tried to delete some of the contour lines that are not needed and purge the dwg file to reduce the size but still getting the too many points and the process will be slow message. And with reduction method not sure how much is it optimal size without losing too much tolerance.

Hi Mick

Because every point along a contour line will be used in the triangulation it is important to make sure that the contour lines are represented by as fewer points as necessary using only the points that are needed to produced a good approximation of the curve.  

It is common when contour lines have been produced using curve tools in CAD and other software (as opposed to being manually traced) that the resulted lines have far more points than necessary.  I wouldn't delete contour lines unless the interval is very small, but focus on reducing the points, you can do this using the tools in Kubla Cubed.

Ultimately the descision in regard to how many points to remove is down to an estimators judgement.  One thing that can help is by looking at the contour lines 'before' and 'after'.  If you zoom into the lines, you will see both the contour lines unmodified and the contour lines with points reduced in a different shade.  You can see visually how far the contour lines are changing and make an assessment as to whether the change is deviated too far or if it is small enough as to not effect the topography that will be produced. 

If you aren't seeing these lines it is probably because the points you are removing are having very little discernible effect on the contour shape and it can only be noticed by zooming in.  The point reduction algorithm is very sophisticated and will remove points that contribute little over ones that are used to define dramatic changes in the contour.  You can often remove 1000's of points before noticing a significant difference in the lines at the standard zoom level.  I would zoom in  a bit though using the middle mouse wheel to get more clarity on what is happening.

If you are still stuck after playing around send the file to support and we can talk you through the process sharing screens.
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#3

Thank you for the promote response. I have followed your recommendation and play around with, it's working fine now.
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