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*Expert Elite*
Posts: 1,091
Registered: ‎06-03-2011

# Re: PNT files

03-16-2012 11:43 AM in reply to: Jeff_M

Jeff_M wrote:
does he shoot contours, or does he shoot points with elevation?
He shoots points with elevation, then he comes back home, and the very first thing he makes is.. contours from those points.
Contours are the base for every serious topographic plan: how did you project before computer era?
Answer: in 2D, on a contour basis, trust me.
If somebody lets me choose between a bunch of 3Dfaces (TIN) or a shape with elevated contours, I go with the second one, without no doubt, dear Jeff.
Distinguished Mentor
Posts: 661
Registered: ‎07-30-2008

# Re: PNT files

03-18-2012 03:11 AM in reply to: antoniovinci

antoniovinci wrote:

Jeff_M wrote:
does he shoot contours, or does he shoot points with elevation?
He shoots points with elevation, then he comes back home, and the very first thing he makes is.. contours from those points.
Contours are the base for every serious topographic plan: how did you project before computer era?
Answer: in 2D, on a contour basis, trust me.
If somebody lets me choose between a bunch of 3Dfaces (TIN) or a shape with elevated contours, I go with the second one, without no doubt, dear Jeff.

The first thing that gets done with points are that they are added to a surface in civil 3d from which trianlges are created, from which contours are interpreted. Check out what gets changed when contours are smoothed.

When I carry out a topo survey I measure points (and breaklines) that will create a surface model that will give the best representation in the computer of the actual ground, based on triangles.

Before computers, surfaces were drawn with contours, which were calculated from the points that surveyors measured. The surveyed points were plotted onto paper then measured between to calulate the elevations that were to be drawn as contours. The contour lines would then be drawn smoothly between all the calculated elevations of the same height to give your contour plan. The same process that occurs with a tin surface in computers.

If this fixed your issue, click on "Accept as Solution"

Andrew Puller
Maitland, NSW, Australia
Windows 7 Enterprise 64bit
Intel core i7 2600 @ 3.40 GHz with 16GB Ram
Civil 3d 2013 64bit
*Expert Elite*
Posts: 2,384
Registered: ‎04-27-2005

# Re: PNT files

03-18-2012 10:55 AM in reply to: antoniovinci

Contours are a lie. I would MUCH rather have the triangles of the surface then an approximation of the surface aka contours. If you build a surface from contours, what is happening between the contours? You have absolutely no idea. If you get the triangles, you have the maximum amount of information from that surface. Do you build from contours? No. You build from points. The contours are simply a graphical representation of those points that make it simple for us as humans to see what is going on.

I hate to say it but I disagree with you, Antonio (I'm assuming that's your first name). But hey, that's the great part about this discussion group, people disagreeing with you is a great way to learn.

*Expert Elite*
Posts: 1,249
Registered: ‎09-05-2006

# Re: PNT files

03-19-2012 09:27 AM in reply to: BrianHailey

Brian:

The biggest problem that I have here is agreeing with Jeff, ALL THE TIME.

Oh well, maybe, someday!

Bill

Contributor
Posts: 14
Registered: ‎03-29-2011

# Re: PNT files

03-19-2012 03:11 PM in reply to: Jeff_M

I am going to consider this issue resolved for me.  In future I will ask for LandXLM file.  I was actually looking for points.  When I received the .txt file with point information, I imported .txt file and got what I was looking for.  I appreciate all the good answers.  When I called the surveyor, he didn't know anything about a .pnt file. I use him regularly therefore I will just get the .txt file and insert it.

Thanks again,

Mando