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Pasting Surfaces

28 REPLIES 28
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Message 1 of 29
Pointdump
1639 Views, 28 Replies

Pasting Surfaces

Struggling to understand some key concepts, and Helpspeak is my second language.

 

From the Help Section:
"You cannot paste the grading surface into the surface that you are using as the target surface. This is disallowed because of the dynamic relationship between the gradings and the target surface. To accomplish this task you should create a copy of the target surface and paste the grading surface into the copy."

 

1. Why do they refer to pasting the grading surface INTO the target surface? Shouldn't one surface be pasted ONTO another? Yes, that bothers me.

 

2. Why can't you paste a grading surface onto a target surface? I thought "dynamic relationships" was what Civil 3D is all about. How do you make a copy of the target surface?

 

Dave

Dave Stoll
Las Vegas, Nevada

EESignature

64GB DDR4 2400MHz ECC SoDIMM / 1TB SSD
NVIDIA Quadro P5000 16GB
Windows 10 Pro 64 / Civil 3D 2024
28 REPLIES 28
Message 21 of 29
troma
in reply to: Pointdump

You have to look for the loop.
If you paste into the original, you get:
Existing Ground Surface > Grading > Grading Surface > Existing Ground Surface > Grading >Grading Surface > Existing Ground Surface > Grading etc.

If you paste into the copy (I call the copy "Composite Surface"), you get:
Existing Ground Surface > Composite Surface
and
Existing Ground Surface > Grading >Grading Surface > Composite Surface

As you see, there is no loop. It all ends at the Composite Surface. And the grading is targeting a surface that doesn't change (unless there is updated topo).

The Composite Surface is made of two pastes: paste in the Existing Ground Surface, and then paste in the Grading Surface.

Mark Green

Working on Civil 3D in Canada

Message 22 of 29
Pointdump
in reply to: troma

OK Troma, now we're getting somewhere.

 

"The Composite Surface is made of two pastes: paste in the Existing Ground Surface, and then paste in the Grading Surface."

 

So a pasting operation is distinct, and completely separate, from the drawing, unlike, say, draping a feature line over an existing ground surface? Or can you paste a surface into an un-pasted surface? I'm starting to understand Tim's suggestion of pasting into a blank surface to make a copy.

 

"...targeting a surface that doesn't change"

 

What is it about a COPY of a surface that doesn't change, but the ORIGINAL would?

 

Dave

Dave Stoll
Las Vegas, Nevada

EESignature

64GB DDR4 2400MHz ECC SoDIMM / 1TB SSD
NVIDIA Quadro P5000 16GB
Windows 10 Pro 64 / Civil 3D 2024
Message 23 of 29
troma
in reply to: Pointdump

If you paste into the original, you are pasting into the same surface you are targeting. This creates a loop.

If you paste into a copy, you are still targeting the original. So you target one, and paste into the other. This avoids the loop.

You do not target the copy! The copy does change!

Mark Green

Working on Civil 3D in Canada

Message 24 of 29
Pointdump
in reply to: troma

Thanks, Troma.

 

"If you paste into a copy, you are still targeting the original."

 

I gave you a Kudo for that. If acceptance grows into understanding, it'll be a "solution" too.

 

I thank you very much for your efforts.

 

Dave

Dave Stoll
Las Vegas, Nevada

EESignature

64GB DDR4 2400MHz ECC SoDIMM / 1TB SSD
NVIDIA Quadro P5000 16GB
Windows 10 Pro 64 / Civil 3D 2024
Message 25 of 29
fcernst
in reply to: troma

You have to look for the loop.

 


Why does there have to be a loop? I agree with Dave, not a very dynamic performance by the Grading object.

 

First scenario:
-Grading object executes Daylight to Target Surface

-Grading object surface updates.

-Target surface updates

-Grading object doesn't move because Daylight points are still the same.

-STOP

 

Second Scenario:

-Add data to Target surface

-Grading object daylight moves

-Grading object surface updates

-Target surface updates

-Grading object doesn't move because Daylight points are still the same.

-STOP

 

The only thing is you would not be a able to come back in with your Daylight slope; say from a 10:1 back to a 3:1 unless you added data back to the Target surface first that would allow the Grading object to again Daylight at 3:1.

 

 

 

 



Fred Ernst, PE
C3D 2024
Ernst Engineering
www.ernstengineering.com
Message 26 of 29
troma
in reply to: fcernst

Are you explaining how it does work, or how it should work?


Mark Green

Working on Civil 3D in Canada

Message 27 of 29
fcernst
in reply to: troma

This is how it should work. It's less overhead for the drawing and the User than making a copy of the Target surface in the drawing. Who wants to keep track of all that?

 

Sounds like the algorithm needs some work in this area.

 

I would amend my post to say that you could also just hit Undo to get back to your 3:1 from the 10:1 example, or you could add additional needed data to the Target surface.



Fred Ernst, PE
C3D 2024
Ernst Engineering
www.ernstengineering.com
Message 28 of 29
troma
in reply to: fcernst

 

I really don't know much about how all the data management and processing stuff works behind the scenes, but I would hope that a surface created by pasting in two other surfaces doesn't put barely any overhead on a drawing.  There is barely any additional data for it to process.

On the point of:

" -Grading object doesn't move because Daylight points are still the same."

I would question how that can work.  If you grade from a featureline, create an automatic surface from grading and paste that surface into the target surface, is the daylight still the same?  Isn't the grading going to intersect the target immediately, seeing as the target surface now extends to the precise location of the featureline?  So the grading routine would have to add some function to check the target for being collinear, and if it is to target the far end of the collinear section rather than the near end.  Either that, or we need some object that recognizes that "I am a surface, and I hold this definition (EG) and that definition (grading), and I respect the dynamic interaction of both definitions with each other".  It seems to me that the composite surface is a good solution for that.

 

Another reason for copying the Existing Ground rather than pasting into it, is that you'll probably need it later.  Don't you need to show the original contours on your plans?  You don't edit the Original Ground topo with design information!

 

Actually, I'm not opposed to your suggestions.  But I do think there's a reason for the way it is.  And if I were suggesting improvements to the grading routines, this wouldn't be top of my list.

 


Mark Green

Working on Civil 3D in Canada

Message 29 of 29
fcernst
in reply to: troma

If you grade from a featureline, create an automatic surface from grading and paste that surface into the target surface, is the daylight still the same? 

 

 

Why would it be different?

 

Paste

Target surface updates

Grading object executes

Grading object Daylight does not move because Daylight points have same X,Y,Z solutions

STOP

 

 

Don't you need to show the original contours on your plans?  You don't edit the Original Ground topo with design information!

 


On construction documents yes, but we don't need Autodesk to Nanny that for us, right?  What about the visualization purpose?



Fred Ernst, PE
C3D 2024
Ernst Engineering
www.ernstengineering.com

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