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CADMAN33619 · Joined: 21 Jul 2009 Posts: 23

Hi All,

is there a lisp that will give you grade elevations after picking start/end points and entering the desired slope? (or something similar)
I've heard of something like this before. I'm not very good at determining what the grades should be for two points with a desired slope and I have not been able to find any tutorials to help.

Thanks
Cadman33619

CarlB · Joined: 27 Sep 2005 Posts: 121

Do you mean you pick 2 points, and provide an elevation of one point, and a slope, then you want the lisp to place markers where the even feet or meters are located? Or do you want to specify some grade interval, say "0.25 feet" and have all those shown? Please elaborate. I may have (or can create) something similar ..

CADMAN33619 · Joined: 21 Jul 2009 Posts: 23

not exactly, Carl...

for example...adding new grades to a parking lot...I have an existing grade of 32.43' at the first point. I need to set a new grade at the second point. I know what my slope should be (1%) and i know what the distance between the two points is (30') but i'm not sure what the new grade at the second point should be.
I know there is a method to figure it out but i'm not sure what it is. I thought maybe there was a LISP that could automate this task. The areas I need to set grades for are pretty large and it could take quite a while to figure them all out.

Thanks
Cadman33619

CarlB · Joined: 27 Sep 2005 Posts: 121

Probably hard to find a lisp that does exactly that. Also depends if by "point" you mean an AutoCAD point object, and if you want the routine to place the new elevation text, etc.

the calculation is simple, PT2 elev=Pt1 Elev+ (slope x distance)
The lisp could do just the calculations and give the second elevation, or could actually place the elevation text. It would have you pick an elevation (say a text object), ask you for slope (+ for up, - for down),. If just text, it could use text location as the starting point, or ask for the starting point. Then pick 2nd point, and list could report the elevation, or place the text, maybe a copy of the first selected but elevation modified. So many options Smile

CADMAN33619 · Joined: 21 Jul 2009 Posts: 23

That sounds like exactly what I need... The first point would be an existing grade from the survey...the second point would be a new location for the new proposed elevation grade.
Sure wish I new how to create these things.

Thanks

CarlB · Joined: 27 Sep 2005 Posts: 121

If you email a drawing which includes a "survey point" and an elevation label I can put something together.
cab AT eeiteam DOT com

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