Terrain problems

[ChrisO]

Can anyone teach me how to make terrain that doesn't have strange bumps, troughs, etc all over the place? I've been trying for days.  Everything I do results in a complete mess.

The help webinars make its all look so darned easy, but it just doesn't work they way they show it.

 

Home Designer Architectural 2021

   

[DavidJPotter]

If you are using elevation points as opposed to elevation lines, splines then I am not surprised that you are having difficulties. I never use elevation points, they are hard to see and find to edit them after the fact. The basic datum for terrain is that the software will generate a gradient from one elevation value to the next elevation value. For abrupt changes in terrain you use the "Terrain Break" object to define abrupt changes. Try to keep your terrain as simple as it possible and laid out smoothly from end to end. I realize that the "real world" often does not follow this maxim but most land used for structures does. Having two elevation values too close to one another or vastly different elevation values causes a bizarre world end product, so keep your modulation of the terrain plodding, checking each change to track if it was correct or not. If that change looks weird, then stop, alter that change and then check again until you get the right looking product. Like every thing else, in this software the product you see is what you created, so it it sucks, you made it that way. Find out how to do it right and through trial and error practice you will eventually arrive at personal competence.

 

DJP 

[ChrisO]

I have tried using elevation lines and elevated regions, but the videos said avoid elevation points so I did not use them.

I am tearing my hair out over this. It is ******* driving me witless.

[DavidJPotter]

Can you explain what is wrong, a section at a time please so specifics could then be addressed?

 

DJP

[ChrisO]

Here's an example.

I opened a new plan, completely clean.

I created a terrain perimeter.  Changed the material to tiles so that the lines will show any strange shape anomalies.

I created an elevated region and set the elevation to 5m.

I copied the elevated region, and pasted it next to the first region, then moved them together.

I changed the second region to height 4m.

 

As can be seen, a number of irregular anomalies were created.

Look at the tiles on the 3D picture; the disturbances are all over the place.

Look at the join between the two regions; it is not uniform in any way.

Look at the contours at the lower end of the plan. They are skewed towards the right hand corner.

 

     

 

 

So now the assumption is that a straight retaining wall should tidy up the anomalies.  It does a fair job, provided it is placed with pin-point accuracy along the whole length of the region interface. But there are still anomalies.  

 

 

 

And, if you alter the length of the wall and do not cover the whole interface across the entire terrain, then the anomalies spread all over the terrain. You might think these are too small to matter, but when you add more elevated areas the effect multiplies, and eventually you ca get some really crazy shapes

 

   

 

Now I've added a terrain following wall, and placed a retaining wall at the bottom of the slope between two elevated regions.  Look at the results.

[ChrisO]

Sorry to say it, but the terrain function is just a pile of wombats doos.  Hours and hours wasted...  This went from a fair model of a stepped hillside to this. Every time the terrain is built, it gets worse.  I'm struggling to keep a polite tongue in my mouth.

[Jo_Ann]

The elevated regions are shown with different hatch patterns.

The side walls are regular terrain walls,  and the horizontal walls are terrain retaining walls.

[ChrisO]

Thanks. That's very close to what I am trying to do.  Can you send me that plan and let me look at it?

 

There's one significant difference to the real situation: There is a road along the left hand edge of the terrain, and the road height is about 1m below the height of the terrain on the other side of the wall.  Therefore the wall has its base on the lower side (the road). Would that make a difference?

 

 

10 hours ago, Jo_Ann said:

The elevated regions are shown with different hatch patterns.

The side walls are regular terrain walls,  and the horizontal walls are terrain retaining walls.

 

[ChrisO]

We seem to have a workable solution now. 

The method of butting elevation regions up against each other does work, but it is a brute force solution and it causes very slow 3D rendering. Even the smallest error will produce huge anomalies.

Having worked with the tech support guys, the following method works reasonably well:

1. Separate the elevation platforms by a distance that would result in about a 45 degree slope. Without the retaining walls, this is displayed as a fairly even ramp between the two heights.

2. Place a retaining wall mid-way between the two regions. This will display as flat land above and below the wall. If the terrain slope leaks through, separate the regions more, or reduce the height difference.

3. When building outdoor stairs or other objects that sit on or across the gap between the regions, cut the retaining wall and rebuild it beneath the object such that the edges don't quite show. This has the effect of preventing the terrain building under the object and penetrating it. It's only needed if the terrain shows through.

4. Contrary to what is shown in some of the help videos, it is not a good idea to use terrain holes because these somehow stress the terrain calculation and cause oddities.

5. If you change terrain height, you must check objects like chairs etc. They will be suspended in mid air or buried underground. To restore them, just open the object and save it again.

6. Do not not stay in terrain-tool mode for any longer than necessary. The slightest error can cause a small elevated region that is incredibly hard to find.  Similarly, avoid using elevation points and elevation lines. A very thin elevated region is easier to handle.   I'd recommend marking any small areas with text or an object so that you can find them again.

7. Extend the elevated regions outside the terrain perimeter. It seems to use few contours.

8. Use "Fill" to colour your elevated regions. It makes it easier to see what is going on.

9. Use the "draw order edit tools" to bring objects to the front so that the elevated does not get selected first when clicking on an object.

10. Save new versions frequently in case to do something wrong and cannot find the error. 

 

I found that it is easier to use the "absolute elevation" settings when working with objects on the terrain. That's personal preference caused by the need to set room heights to get a particular shape of roof.  It also applies to plants and trees because they like to be sat on the floor, but you might not know where the floor is without doing a mental calculation.

 

I still do not have a solution to the weird behaviour of retaining walls connected to other walls.  

The upper landing required for outdoor stairs doesn't seem to work properly if you use the automatic height setting (I'm using the Mac version). Set the height that you need. The lower landing seems to work fine.

There's another problem with retaining walls in that the app can suddenly decide that any additional retaining walls are too complicated and it starts to throw warnings.

 

I await further answers from tech support.