Need help with setting height on a contour map

[Elo]

Hi, this is my first post so sorry if I've put this in the wrong forum.

 

I'm about to start modelling the house we're building in max, but I've run into a problem I'm having some difficulty with. Now I've modelled a house and site before in tutorials, but the survey files I've worked with before have all had the contours set at the correct heights. I've been looking online for a week now and I haven't been able to find any tutorials or advice on how to take a survey map that's flat and push all the lines up to their correct heights. Now I'd just move the lines to their indicated heights by setting their z values to their correct heights, but looking at the file has me confused as to exactly what those heights are.

 

The brown lines are marked with one metre in between them, but the cream coloured lines in between those aren't marked with heights. Each of the red dots are a height marker though. What confuses me is that these markers don't sit on any lines but the few red lines that you see, and even when they do sit on a line they're marked with varying heights, which as far as I can gather means that the line doesn't sit at one height, which kind of throws into question the red lines usefulness as a contour line. I just don't know how to interpret what I'm looking at.

 

Because this is the site plan for the house I'm planning on living in for the next 20+ years, I'd like to get the terrain and model as accurate as I can get it.

 

If anyone could offer me some advice on how to best do this, or a link to a tutorial I'd be much appreciative. I'd be willing to pm anyone who's willing to help me the dwg file to look at if it'll help you see what I'm talking about. I'm using 3dsmax 7 and I'm unsure what version number the surveyors cad file is.

 

Thanks in advance.

[Virgil Johnson]

I can't really see the drawing clearly...

 

so let me ask some questions and see if they make sense.

 

First is this the existing or final grade contour? (Looks like the existing to me.)

 

Are the red marks survey points? (Points where the elevation was measured.)

Do these represent important points - corners of buildings - road elevations, etc.

 

Do the red lines indicate the boundries of the graded terrain? Are these areas to be "flat"?

 

Are the brown lines 1 meter different in elevation? - leading me to think the division is measured with the cream lines.

 

hope this gives you a start

 

Virgil

[Elo]

First is this the existing or final grade contour? (Looks like the existing to me.)

Existing.

 

Are the red marks survey points? (Points where the elevation was measured.)

Yes.

Do these represent important points - corners of buildings - road elevations, etc.

No.

 

Do the red lines indicate the boundries of the graded terrain? Are these areas to be "flat"?

No.

 

Are the brown lines 1 meter different in elevation? - leading me to think the division is measured with the cream lines.

Yes.

 

 

I'm looking for advice or a guide as to the best way to turn this into a terrain.

[Virgil Johnson]

To make a terrain...

 

Put the contour lines on the different levels and use the terrain command in Max. (under "compound objects")

 

Check out the help files if you are not familiar with this.

 

To get the z values just look at the called out elevations and the (cream) divisions between are even increments going up or down depending on what is called out at the major (brown) lines

 

 

As to the red lines... are you sure these are not the final grade contours?

 

As to the red markers...there must be a reason why these points were chosen for an elevation measurement.

 

But without more information about the project I can only make guesses.

 

I have done dozens of these projects and always the existing contours were shown with grade plans on them.

A part of the site has to be changed to build something.

 

Otherwise buildings would poke into the ground or sit in the air at different corners.

Unless of course you are building on a perfectly flat site.

 

The survey points told me where to put the models as to XYZ.

(Without this information how would you know where to put buildings, etc.)

 

Virgil

[Elo]

As to the red lines... are you sure these are not the final grade contours?

 

No they're not, but they may as well be as only a small corner of the house is going to be on a slab and cut into the ground, the great majority of the house is on pillars. We're keeping earthworks to a minimum given the rockiness of the land. One of them is marked as a transverse line, but it's just a line between a power pole and a steel peg the surveyors put in the ground. At first I thought that the red lines corresponded to exposed rock, as the area is cut through by several layers of exposed rock, but when comparing the site to aerial photography, from google, the lines don't exactly match up. That said, rock is really the only thing the lines could represent.

As to the red markers...there must be a reason why these points were chosen for an elevation measurement.

I don't think so, as they're in a grid, sometimes they've taken two measurements close together when there is a sudden drop though.

 

Thanks for your help Virgil, I'll have a fool around with it today and post what I've done. I've got some concerns about the lack of scale indication, but that'll only be a problem when I'm modelling the building.

[Horhe]

You could also turn these splines to nurbs and use the u or v loft - but youd have to be careful not to get a heavy mesh. If you set the tesselation on low or medium, convert to mesh and optimize it you could probably get away with the mesh weight and be happy with it.

 

Or use the crossection and surface modifiers - but this could be a bit tricky. Be sure to place the ending points in the same row or collumn - reverse the spline if needed - or break and weld that very point you need at the end.

Same goes for nurbs.

 

Otherwise its skewy screwy skew... or somethin like that

 

First go for the compound terrain thing in the jig that should work ok

[Elo]

I sorted things out by just ignoring the elevation points and going by the contours, but now I've got another, related problem I need help with. The imported autocad file contained no kind of scale, I don't think they usually do, it's just that I'm about lost on where to go without it. Just used generic max units to set the height for the contours as it should be fairly easy for me to scale them correctly.

 

So my question is, how do I get this terrain to correct scale?

 

The only thing I can think to do is get my hands on a very long tape measure, and measure the distance between a power line pole and a metal stake that are both marked on the surveyors results. Are there any easier ways of doing this?