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How real terrain ?
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* October 28, 2018, 06:46:57 AM
I would like to ask how to make a fairly real terrain around the building.

Terrain command
Great idea. Theoretically and in demonstrations it works well. But practical application?

When using any real terrain (geodetic focus), significant degenerate areas are created at the boundaries of the component. They can not get rid of them, they can only be slightly smoothed by inserting auxiliary non-existent points.

Some idea?


* October 28, 2018, 08:23:07 AM
You could try to use Edit tool and delete the nodes that are going down to workplane, or make a rectangle/ closed Polyline over the bad area and use the Terrain Modifier on it.
This fault's is normally in the mapfile you make the terrain from.
Another option is to explode it one time and Slice or Subtract the bad area, but of course, then it's not a terrain anymore, but can be very handy to work withe the boolean tools if you should have many different plain levels side by side in the terrain.
And if you should have a "hole" for Foundation walls ore something you can use leave subtrahend and later select that bit for find the volume of it.
If it's a big area, you also then have the option of using Surface Simplifier to take down the filesize and it's more easy for TC to work with, aka smooth moves when rotate for different views


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* October 28, 2018, 10:17:19 AM
Degeneration can not be corrected by editing nodes. There are no nodes in the degeneration.

Terrain modifier - on a 3d collapsed area? I'm talking about real terrain and not some simplification. I would definitely welcome terrain modification by 3D curves.

The error is not only in the mapfile. It's also in the manual creation of terrain by the mouse.

The problem is in the terrain algorithm. It combines all boundary points without distinction.
If the boundary (perimeter) points are approximately in a circle, then the terrain works perfectly.
But this is not a real state. The landscape with which the designer works usually ends on a straight edge. Building, wall, fence, etc. All the points are linked to this edge (in line).  And there (in line) is needable degeneration. You can limit it by inserting other nodes. But just limit it. It always stays there, it will not be so pronounced.

Editing (Slice, etc.) is a problem. Although I can adjust the surface afterwards, but the body will become individual boundary surfaces ( hollow body with circumferential surfaces ). And so I can not find the engineering properties. As a volume of earthworks, etc. So it is just for rendring usable.

I do not know.
Perhaps it can not be professionally used. The circumference of the terrain is never a circle. It is limited by the surrounding area, the boundaries of the land. It's a rectangle, a trapezoid, or a L or T shape. If there is an inner corner there is a problem. He works quite reliably with the outer corners. The borders points on the line are treated as an inner corner. And that's wrong. Only the closest perimeter points must always be connected, regardless of the others.
There are also different edges and fractures on the real terrain. Only rarely are 2d curves and areas (the terain modifier can not be used).

Usually I prefer to create terrain using lofting, but it is not so easy.

An experiment file is attached.
After much simplification. The original terrain is in layer whith red colour.


* October 28, 2018, 11:02:56 AM
I'm talking about terrain modifier to cut away the bad parts, see Attached.
In pic 2 i also put on the original terrain so you see why i want to take away that part, it look "funny" in perspectiv view in that direction.
And i talk about when we order and get dxf/ dwg terrain from government, not a "home made", i seldom have errors if i do that, but it's not worth the time used to it if i can get a file with all the info i need for relative little money, and the one i order is more correct than the one i can make by trace P.lines over a map or similar.

If the Solid is hollow, you can try to make a Surface from Solid and then make a Solid from Surface, that will many times cure it, and you should always make a bigger terrain then what the actual plot is, so you can cut away what you dont want to see is my experience


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* October 28, 2018, 12:19:48 PM
It looks like a smart solution, but it can only be used occasionally. Because ...

The geodetic focus for construction is limited to building land and publicly accessible adjacent streets. The surrounding land may not be accessible. Even - mostly not accessible. Maybe as an attachment. Orange color is what is targeted. Surroundings are not accessible for focus.

If I use the modification according to the written one, I will leave half of the building land. And the most important thing is lost - terrain at the boundary of the building site. At the boundary of the land I have to exactly connect and / or suggest a wall, sloping etc.
Only half of the terrain I need? That's just unusable.
So I stay with terrain created by lofting. It's challenging, but it seems to me less than other methods.

For me, it's a program bug. The terrain command must link to the edge only the most bold boundary points. Not all. It probably will not happen automatically. There is no possibility of defining the boundary curve (boundary points from the terrain). Then it should work as it should.


* October 28, 2018, 01:07:31 PM
I got all the info i want/ order in the mapfile i get from government, but it is like it original terrain was before there was buildt something on it, so any thing that have been done with the terrain on the area around the plot i only get in 2D and will need to have someone to go out there and meassure the z values of it if needed, normally we dont need it for the architectual drawing.
That drawing is used for a splitted Application of building something, if that looks ok for the government, we send out People to get the exact messurement of Z values and borders as the map we get can be maybe 20-30 cm wrong, but it is the same map building Department have, so they cant complain on it :)
I also can get the waterpipes, eletrical cables, ligth poles for streetligth etc if i want too.
The blue houses on last attachment  i get the info , rim and bottom of roof pluss length and by that i cab put out a simple house so they can see the Project comperred to the other in the area, and i have a ppm that making them based on this 2 infoset and i just snap it to the middle rim and rotate them a bit.
I need to show how the area will looks like in a line follow the Outer side of the building to/ across the border, but that i do with the Drafting tool on the building and terrain, very easy :)
Then i show original and planned terrainline in the drawing, see Attached.
BTW, the map cost normally about 210 US $ incl tax, and was what i payed for the terrainfile in this project as well


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* October 28, 2018, 02:43:43 PM
I begin to feel like we're talking about something else.
You are talking about land-use planning and I about the project of a particular building.

Government maps sufficient for land-use planning, but certainly not for a project of a particular construction that must be precisely fitted. And exactly connected to the surroundings. 20-30cm difference? Often there may be a 5cm big problem !!. Because you may have to run water into the house. Or you do not meet the regulations for the disabled. Or a ramp at a hall without a leveling platform at an existing road. Etc.

I thought designing was the same across Europe or at least similar.
If I'm designing a particular building then I need the basics first. And these are :

1. Cadastral map
2. Precise geodetic focus of building land
3. Map data of utility networks from their owners (eletro, water supply, sewerage etc .. They are dgn.TuroCAD and dgn this is the chapter for itself)
4. Different surveys (engineering geological survey, radon measurements, noise, etc.)

Only then can I start doing a project.
Without it, it's just a study, just pictures that can be a 30cm error with no further consequences.


* October 28, 2018, 03:50:59 PM
Nope, i think we are talking about nearly the same thing, in an Architectual drawing it's not important if the Z value is 25 to 30 cm wrong from what it is in the real world, i dont plan waterpipes etc at that time, actually i never do, the plummer take care of that, i only make sure that it is correct when we are applying for the permit 2, to start building, we already got an pre permit for building it, then we have checked the Z values and have the correct Z comperred to the real life, it's not difficult to lift a house in the drawing, or lower it if that is what we need, and adjust the terrain or ramp to it.
The only thing i need to make sure of is that there is min 90 cm from the bottom floor to the bottom of the place where the plummer should connect to the main pipesystem for water out of the building.
In the pre permision the government will tell us if we need to adjust something to that higth, we also get a drawing that show the water pipes when we order the neighbor list to whom we should inform about the buildingplans, then we also see if we need to move the building or the pipes if they are crossing the building somehow, and of course the same thing with eletric, gas and telephone etc, but the heigth of it is not important in the beginning.

That said, i dont work with big buildings, max 3-4 units and after the Architectual drawing we need to produce the Engineer drawing, that has to be accurate, but why waste money on a survey if you dont get pernission to build it anyway, so we wait until the pre permision is given, make the Engineer drawing and then we make the Construction drawing based of the permit and we know exactly what we are allowed to build and where pipes etc are.
Somtimes, but very seldom we need a survey before apply for pre permit, but that is only if the area have changed alot since the terrain was messured, the customer want to really max whats possible on the plot, i think to remember 1 time the last 10 year or so.


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* October 29, 2018, 03:42:42 AM
I'm not sure we're talking about the same thing. Yes and No.
The building permit process may be differently called in different countries. You are typing a "pre premit", architectural drawing.  I'm writing about a " and-use planning" and a study, the exact name is in our country: „decisions on the location of the building“, in Norway is called mayby "pre premit." But it is same – any „phase one“. The terrain height, if any, can be +30cm.

This first phase does not interest me. I'm not talking about that. I'm only interested in the second phase.
How do you write about „permissions“ and „Engineer drawing“. The „building permit“ contains the exact floor height of the first floor (- + 0.00 = xxx.xx). This must be included on each drawing. When changing it, you need „application for permission to change the building“. And this can take 3 months, even more (in Czech, really !!!) And the construction will stop for that time. Here I need a precise geodetic focusing of the terrain. I'm talking about it.

The discussion about the differences in the design and construction process is interesting, but I am interested in others. How to make a terrain model. Quickly and accurately.

The Terrain „command“ is a great idea. Its practical use is very problematic.
At the borders there are degenerate areas. These must be subsequently modified. Terrain modifier, trimming, inserting other nodes into the terrain. And that's a lot of time consuming. So, I'd rather use lofting to create terrain. From a 3d point, I create 3d curves from which I create a 3D terrain using lofting. Sometimes at one time, sometimes in parts, with subsequent joining of parts. This creates an almost accurate terrain model, incl. edges and breaks. At the border, the edge, is almost absolutely accurate. However, it is very time consuming.

The problem is that the terrain connects all the nodes. On the periphery, especially if the boundary on the line, only two nearest nodes are to be connected. All distant nodes (on straight line) should be excluded. Either automatically (the program can determine whether or not there are points on a straight line). Or automatically by specifying the sensitivity parameter of the binding range between the nodes or the manual input. Identifying boundary nodes. This would be even better. In the case of the shape of a terrain with inner corners, it is not possible without human assistance to determine correctly the software where the boundary is, the circuit.
It would be great when it was possible to determine what is terrain edge, break, slope. To do this, he would use a terrain modifier, but he would have to be able to work not only with 2d curves but also with 3D curves.

It's a great shame that the terrain command does not work as it should.


* October 29, 2018, 07:11:03 AM
We are talking about the same, only use different words :)
In Norway we have 2 systems
1 step apply that takes 12 weeks, if the government is not happy with the project, they refuse it, we have to pay full fee and make a new applyment, wait another 12 weeks and it goes like this until the government is happy with the project.

2 step apply is what i like to use 12 weeks if they are not happy they let us know what, we dont pay full fee and we dont "loose" place in que.
Second part of 2 step, when they are happy and we want to start the actual building we need to apply one more time, answertime for that is 3 weeks, and the the total fee is only about 50 $ extra, so in other words we save time and money if the project is not 100% inside the regulation law's for that area and to the like of building Department.

So the terrain :)
When i order a terrain i get all the things i need, see Attached in dxf or dwg, i also can get what is special for Norway, Sosi, a txt format but more info inside it
Then i use terrainlines drag out XYZ points info in TC from it and make the terrain, if i need to level one area i use modifier, if there is more i make a copy of it and explode the and use boolean tools on it, original terrain in different layer and close it.
Then it's sort of easy to make the adjustment i need.
It is timeconsuming yes, but i think it's better then using loft for making a terrain and it is the same terrainlines and info that the government use to check, so …..
And TC terrain follow 98-99 % on the terrainlines, so it is pretty exactly in my mind, and best of all, it's included in TC :)

Then the Z Level, the terrain is made from fly over it with plane, using a radar, hence the difference comperred to real life, but it will be like that all over, so it,s easy to just move it a bit up or down when somebody have checked the real z heigth


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