Terrain Model Options_Set Intervals Dynamically

[Paulji]

Tool Options for Terrain Model has the option for setting intervals of existing "flat" contours. This is done by increasing the topo interval based upon the sequence of contour picks using the SHIFT key.

 

Using the "Set New: Interval" only increases in the "positive" direction from the Site (Starting) Height. This makes multiple instances of hills and valleys in a large site plan slightly difficult.  One must use the MOVE tool to tediously rise each contour to the correct height.

 

My suggestion is that the Terrain Model Tool Options include the ability to repeat an interval and change to a negative interval.

See attached.

[¢hris £und]

Been a long time since I had a need to do this, but when I did,  all I had to do was "Think Through"   with the contour lines   That is, even outside of the plane you are going to raise, the lines continue on, and are connected, wrap around etc...

[Paulji]

Wrapping or connecting open segments of equal elevation outside the property boundary (prior to selecting them) is helpful to some extent when using the Set Interval option.

 

The fact that the elevation of contours only inrease sequentially in a positive direction makes the Set Interval option less useful then it could be. Sure there are ways to set each contour line at their correct elevation prior to creating a terrain model but I believe the Set Interval option could be tweeked to take some of the drudgery out.

 

I sometimes deal with properties that are comparatively large ... 60 to 90 acres. These often have multiple hills, valleys, ridges etc.

 

The way I envision my suggestion working is to turn the Positive Interval radio button ON to sequentially increase contour elevations by clicking each contour line going up to the crest of a hill ... then switching ON the Negative Interval radio button and "back-tracking" downwards re-selecting contour lines downward to the low point of valleys. Switching between Positive and Negative Interval directions would work for both open contour lines (those that extend outside the property boundary) and closed contours within the property boundary.

 

The Repeat Interval would be useful for elevating open contour lines of the same elevation height.

 

An alternative to "back-tracking" or re-selecting contours previously selected would be to select any previously selected contour to get it's elevation height in a similar way that the F4 key resets a base point only instead of resetting a 0 value it would get the elevation value of the selected contour line. You would the with a Positive or Negative Interval set ON continue to select new contours.

 

It would also be nice if you could hover the cursor over a contour line and its elevation would display.

 

Hope this makes sense.

[setz]

I usuallly just use the join (objects) tool (not the join lines tool) on all contours of the same elevation and then the selection process is quick and straightforward.

[¢hris £und]

It does,  It would probably be a good idea to display the most recent picked elevation in the Options dialog too, so you can always know where you are, or need to go.

[Paulji]

Hi All,

I'd like to suggest a better solution.  Forget about trying to improve the Set New: Interval option.

 

Better Suggestion:

Why not improve and automate a technique that already works well. The technique is to elevate each contour line one-at-a-time to its correct contour level by picking each contour line and entering a height in the Pick/Info tab/Object transformations/ Z-origin edit box.

After all contours have been elevated, use the Terrain tool /Existing option.

The advantages of this technique are:

1. You can see in 3D the contours move to their positions in space. (This is not possible when using the Terrain Model/ Set New: Interval option.)

2. You can check the height of any contour by picking on it and seeing its height in the Object transformation group. (This is not possible when using the Terrain Model/ Set New: Interval option.)

3. You can elevate contour lines in any order ... this makes it easy to switch from a high contour on a hill crest to a lower contour on the foot of a hill and continue downward on a slope. (This is not possible when using the Terrain Model/ Set New: Interval option.)

4. Lastly, you can enter contour height sequences in either a positive direction or a negative direction. (This is not possible when using the Terrain Model/ Set New: Interval option.)

The only disadvantage of this technique is that each contour must be picked one-at-a-time and Z-height values must be entered one-at-a-time. This makes it a tedious process when creating large terrains.

A better solution is to add a Contour transformation group to the Terrain Model -Tool Options.

HOW THIS WORKS:

1. Click on the Contour transformation option radio button.

2. Enter a contour height in the Starting Height edit box. This will be the Starting Height for multiple picked contours.

3. Enter a value in the Contour Interval edit box . This can be a positive (increasing contour interval) or negative value (decreasing contour interval).

4. Pick contour lines in sequence holding the SHIFT key.

   NOTE: On-the-fly you can then enter a new Starting Height and switch the Contour interval from a positive to a negative value or vise versa, then continue picking contour lines holding the SHIFT key.

5. Contour transformation Option.pdf    

[Paulji]

Hi setZ,  

I'm trying to understand how you use the join (objects) tool on contour segments.  It appears one cannot use the Organize/Join tool on segments but only solid or surface objects.  I get the following error message when I try to create a terrain model using the Set New: Interval option: 

 

   "Object must be a solid or a surface,  Use Create Reference Object for all other types of objects."

 

I get the following error message when I try to create a terrain model using the Set New: Interval option:

 

"Reference Objects are not handled by this tool."

 

If however, I use the Reference Objects to "join" contour segments of the same height into a single object I can raise these segments together using the PICK tool.   Thanks for that tip.  It will be useful.

 

I still believe that my latest suggestion would significantly decrease the time required on complex topo sites with huge numbers of contour lines.   Maybe not so much on smaller topos.

[setz]

Oops,  My bad.  This technique works well in V6.

 

The new Join Tool in V8 is very limited in what it can do.  No more joining of open lines, no more joining of solids and surfaces.  It would be VERY helpful to have full functionality returned to this tool.  I understand the reasoning for which ADS did this, Joined objects of different types behave badly in some situations but the functionality FAR outweighed the issues that could occur.

 

Make Reference is not a very good substitute option because it limits full functionality that Join used to allow.

 

Another related bummer is the lack of "Status of Objects - Single Volume" option.  Kills me every time I join a lot of similar objects together only to have a boolean tool blow them all apart each time it's fired - it's like herding cats all day long.

[Paulji]

Hi setZ,

 

That's interesting.  Good insights.

 

I tried using the Group tool to group two contours on the same contour level.  Using the PICK tool one cannot simply enter a Z-value in the OptionTransformation/ Z origin.  That options do not appear.  So one must use the MOVE tool to move perpendicular to the reference plan.  No big deal.  

 

Then using the USE Existing option of the Contour Heights option you can select all the contours that are raised to their proper elevation ... including the grouped contours.   One doesn't have to explode the group in order for the TERRAIN MODEL tool to work).  

 

Grouping of contours of the same height, however, has no effect on creating a terrain model using the Contour Heights/ Set New: Interval.   

 

Honestly, I don't see any value of using the Set New: Interval option of the Terrain Model Tool  ... unless you are building a terrain model where the contours increase in a positive direction sequentially from one contour to the next. 

[Paulji]

BTW.   Ust for fun...attached is a terrain model using Set New: Interval where the interval is a negative value.

 

[setz]

Set Interval used to be very important!  It was my go-to option when making terrain when using V6 - with joined open and closed lines.  You're right though, without being able to join all types of contour lines now, more complicated terrains from contours at the same elevation are no longer practical using Set Interval.   (I haven't been required to make terrain since I switched to V8 full time about 6 months ago).