Surface Help

[PKINGSTON]

I have been having issues with my computer freezing and I now believe that has some to do with the surface creation. My company is provided with a drawing that has all Lidar for the City. Query and redraw the area I am redesigning. My file for a Lidar-only file is 3294KB but after creating the surface it becomes 20,945KB.

I have tried a different approach with weedfeature for the polylines. I select angle 2.00(d), no grade, length 50.00', and no 3D distance. It weeds out 43763 of 216925. Use 2862KB to 18932KB. 

Is there anything else I can do to reduce the size of the surface?

I shortcut the created surface into my other design drawings.

[neilyj666]

Did you try SIMPLIFY surface?

[PKINGSTON]

When I try that the surface the contour lines distort and attach themselves to other lines.

[PKINGSTON]

The pinkish/green lines join multiple times on a contour line and the white/gray lines do not. @neilyj666 

[neilyj666]

@PKINGSTON  Yes - contours are the most inefficient objects when trying to build a surface and you get odd things happening when the contours make sharp changes of direction. You can try changing the surface build order and move the minimise flat areas to be the last operation but you may possibly get better results if you had the original point cloud data in a file.....🤔. 

The file size will increase as there are many triangles created for the surface although the resulting dwg isn't particularly large in terms of MB.

Have you tried cropping the surface into smaller areas - this is my usual work flow? I work on a lot of windfarms which cover many km² within the site boundary but the actual infrastructure occupies a much smaller area

[PKINGSTON]

I usually try to make my surface the smallest I can. I design utilities and paving projects for my city. I use a rule of thumb to create a surface: 1) add 100' to the alignment length in both directions, 2) extend the width by one block to each side, and 3) use 1' weeding factor and 2' supplementing factor for as many minimize flat areas. The longest project I am working on is 2.1 miles long.

[jefflambert9091 · Accepted solution]

You can "Mapclean" ( I have tried weeding the polylines and tried "PLdiet" but maplean does a better job and is faster) Then create a surface from those contours. After that you can them simplify the surface in the edits (use Edge contraction) to take it down more. The danger is hacking the surface too far and losing the integrity. I always keep the original surface (in its own file) and compare.

[jefflambert9091]

My last post is if you were supplied contours from the lidar data. If you have the lidar data I would recommend using C3D Lidar Tools. Once you have a surface you can simplify by 90% and keep the integrity of the surface.  

[neilyj666]

@jefflambert9091 Whilst it is very useful does Mapclean > Weed Polylines work on 2D polylines?

[PKINGSTON]

@jefflambert9091 That is what I was looking for it reduced my file sizes by half.

[jefflambert9091]

There is Simplify Objects in the Cleanup Actions list. I had to go to help and look at the about and the settings a tolerances. I did not realize how much/many things mapclean does. For now, I just use it for cleaning up contours.   

[neilyj666]

I'd forgotten how powerful MAPCLEAN is...😀...but one has to be careful that the resultant surface is still fit for purpose e.g. a large surface for catchment analysis would be very different to one required for a housing project.

[PKINGSTON]

I will be careful and compare the surfaces using my profiles for the utility and paving project. @jefflambert9091 @neilyj666 

[jefflambert9091]

The best way is to keep the original surface and place it in a different surface style. (I keep it in its own dwg and  datashortcut it) I have a "1 and 5 TINN" surface style with the contour lines being colors Cyan and Blue. I then have my reduced surface in a different style "1 and 5 EG" with the contour lines being colors 7 & 2. If the contours start to move off the original you have gone to far.