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Can VW Export Site Model Mesh and Create a New One Model Base on It?

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This may sound uncommon but I figure it could be the most efficient way for me to grade some sites.


For instance, I am working with a site sourrunded by existing paving.




And I am proposing to have a flat area with a constant slope for drainage somewhere on the site.




But after I placed the pad modifier, I can't propose access from the surrounding as those modifiers will come across the red pad and causing errors.



My question is: is there any way to merge the site modifier---in this case it is the red pad---- with the model, so I get a clean model with a flat area, also free of modifiers, and I can start to place other modifiers without concerning about modifiers conflicts?

I tested exporting model to 3d contours and generate a new model, but this is going to lost details of the existing model, wondering if I can export the model mesh and use it to generate a new one?


Thank you.  

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Try this trick courtesy of @Tom W..  I haven't tried it, but if you decrease the spacing between the topos before ungrouping, you should get a higher level of detail:



Another method I saw for modifying the Existing model was to apply the modifiers then go to Top view, change display to '3D Contours', Ungroup the model which converts it into 3D Polygons, then use these as the source data for creating a new site model based on the modified terrain.



Edited by E|FA
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@E|FA Thank you. But there is another reason stops me from using 3d polys to create model: if the site modifier is riding on a 3d contour, it will want to conform to that immediately, this will cause unwanted results. I attached an example for this.


First model is created on 3d points, you can see the proposed contour streched evenly and naturally




The second model is created by 3d polys, you can see the proposed contour is heavily constrained by those 3d polys.



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Use a Pad Modifier but place a Grade Limits around it. The 'Create Grade Limits from Pad...' command is useful for this.

Update the Site Model. It will look something like this:


Change to 'Top' view + change the 3D Style of the Site Model to '3D Contours'.

Ungroup the site model to convert the contours into 3D Polygons.

Select all the 3D Polygons + use them as the source data for creating a new site model.

The resultant site model will reflect the modified terrain but won’t include any modifiers.

This is the Existing model now:




  • Like 1
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@Tom W. Thank you for the info. I post 2 images in my last chat, you can see the difference betwwen models created from 3d polys and 3d points, the point based model has much better response for new site modifiers, so I am wondering if there is anyway I can export the mesh/point instead of 3d polys. I am aware that 3d polys can be converted to 3d locis but when there is a "curved" site modifier/3d poly the amount of 3d loci is huge.

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Hi @DDD I wasn't aware that the source data a site model was created from - whether 3D loci or 3D polys - would have a knock-on effect on how the model responded to site modifiers... To me the second screen shot you posted just looked like the pad was missing a grade limits. In my screenshots, the blue site model was the original model which happened to be created from 3D Polys. And then the second green site model was my reconstituted version which was also obviously created from 3D Polys. But both seem to behave fine? Doesn't the method described get you what you want as outlined in your original post? 

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1 hour ago, DDD said:


The second model is created by 3d polys, you can see the proposed contour is heavily constrained by those 3d polys.

This one looks odd.  Did you use a grade limit?

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@E|FA No I didn’t, I think my point was that model built on points has better result with new site modifiers. But since Tom pointed out his model which was built on polys worked just fine as long as there is a grade limit, I’ll test it and follow up the result, thank you.

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@E|FA @Tom W. Hi I tested the grade limit on the model, yes the contour looks better. However the problem still exists, without a grade limit the 3d-poly based model behaves differently :


This is the point-based model, I put on a new pad without a grade limit, the contour slopes back to existing surface evenly on each corner




This is a 3d poly-based model, I put on the same new pad without a grade limit, and you can notice the contour slopes back to existing surface in a different manner as they are constrained by lines instead of points, also the labeling is much worse that point-based model



In my case I can only have one big grade limit defining the property line, but when I am grading smaller objects on the site I am not able to put nested grade limits within the big one. If the model is based on 3d polys it will behave like what I showed above. So I prefer to work with points.

But this brings up another question: when I convert 3d polys to 3d points it creates too many vertices. I am aware there is a function to simplify the 3d poly, but the result is confusing:


the setting recommends the tolerance to be smaller than the closest horizontal distance between two neighbored contours.  




the default setting is 0.45" and the result is messed up: I have crossed lines and a couple straight lines are lost



I scale down the tolerance and the result is still confusing



I attached the file below, any direction is appreciated, thank you.

site model(3d points)_v2019.vwx


site model(3d poly)_v2019.vwx

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7 hours ago, jeff prince said:

@DDD have you considered telling your pad to affect the existing site model and have your road affect the proposed?  This can eliminate some conflicts in such cases.

Can you explain what you mean? A pad on the existing model will still conflict with one on the proposed.


What about the point @DDD makes about a site model that uses 3D Loci as source data + one that uses 3D Polys as source data behaving differently when modified? Is that something you've encountered + one should be aware of?


Like @E|FA says this is helpful for learning more about site modelling



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@Tom W. In regards to the use of ex. Vs proposed strategy, I got that from Vectorworks as a technique and I have found it works fine.


in regards to Points vs Lines data... Surveyors collect points and the lines they show in their drawings are an interpretation of the points.  I suspect Vectorworks is no different.  I use points whenever I can because they are faster with more predictable results.

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@jeff prince Thank you Jeff, this is excellent! I was block by the concept of "not having crossed pads" and overlooked the possibility to apply them on existing/proposed sites.

@Tom W. You will still get the yellow caveat but it really works, I'll do more tests but it seems promising.

  • Like 1
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@DDD cool that's good to hear can you explain what you've done? I'm still not clear what difference it makes having the pad affect the existing model rather than the proposed, apart from affecting the cut + fill calcs... but keen to learn more. Thanks!

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@DDD Maybe I'm missing something here, but I'm confused by the intent in the latest file you posted.

Here's what I see.

You have an existing site that you are developing a 3'9" high pad onto in the existing phase, identified as site preparation.  That makes sense.

Then you have two new pads to affect the proposed condition.  One pad sits at 2'11" (below the site prep), and one pad above the site prep at 5'10"

Mmmkay.  What is the desired outcome in this situation?  Would you not have a retaining situation where these pads sit over or under the initial site preparation OR are you going to bring in a fill to resolve those edges and blend them with the site preparation?


Given that design choice, how do you expect Vectorworks to grade for those pads?  With the information provided Vectorworks is attempting to resolve the edges of these pads and bring the grade to them.  I can see why Vectorworks is confused, or maybe I just don't get it.

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Posted (edited)

@jeff prince Hi Jeff, the design intent doesn't matter that much  in this case. I am creating an exaggerated example to show the problem of having crossed pads although they are applied separately to existing & proposed site model. Kind of like re-painting a wall, my goal is to "wipe" the existing irregular grading by creating a pad to the existing model, then to add proposed grading objects on it, and let them take precedence whenever there is a conflict between the existing and proposed. As you can see, where the pads are crossed, the proposed grading objects do not take precedence completely and errors are showing.


The goal is to have the two proposed pads (top and bottom) to be flat, and grade back to the "preparation pad" correctly.



 Please let me know if that makes sense to you, thank you.


*I attached another mockup by adding two grade limits for the proposed pads and it looks more like it, but the problem still exists as you can see those irregular points. If we can make the small pad flat then this is what I am trying to achieve.




Edited by DDD
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@DDD I think based upon what you want to accomplish, it would be best to create versions of the site model corresponding to the construction operations, incorporating each previous operation into the next model's existing site data.  That should give you fine control with these exaggerated situations.  I suppose I haven't seen this kind of conflicts because my grading operations aren't so severe, or when they are, I'm using retaining structures.

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