How-to: terrain mesh

[Arcadia]

I want to know how I can trim the base of my mesh. I have my project zero set to a finished floor level of 99m and my 1st reference level at 0. When I put my mesh in I used a level of 0 to 1st reference level then put in my contour lines at the appropriate levels between 96m and 99.5m etc in relation to 1st reference level. This is all fine and the mesh shows at the right hieght in relation to my floor level. However I now have a mesh that is essentially a column 99m high. This makes 3D navigation a pain as when I use the orbit function it sometimes picks a spot in the middle of the mesh to rotate around instead of the model and I get wild swinging instead. Also when I export to VBE you sometimes drop in off the mesh and end up down at reference level which means you have a long way to fly up to floor level. How do I keep my levels at the correct 99m above reference (in other words without having to assign assumed levels) or whatever but then cut the base of the mesh so that is only say 2m below my lowest mesh level so it more manageable. Sorry for this long explanation!

[David Maudlin]

Arcadia:

I may be missing the issue, but the height of the Mesh's base can be set in the dialog box (or Info Box). I this is not the solution, then post some images illustrating the problem.

David

[Anonymous]

David is close to the good solution. In order to avoid what I call the candle problem (a huge column below your terrain) you have to do the following :

1 . Before modeling your terrain set the reference level of the mesh (second input on David image) to be very close or equal to the lowest point of the terrain, in your case 96m, and the terrain skirt (highlighted on David image) to be very short, 1m should be enough

2. Then when you input the height of the points and the lines, use the zero project reference, in spite of terrain reference level, this way you will be able to input the real height of all the points

3. Watch in 3D you get using this method terrain with a short skirt. Even if you made a wrong calculation and have to push lower the bottom of the mesh adjust it with the value of the skirt, you will then be able to have some points below terrain reference level

[Anonymous]

You can fix your existing one most easily by just stretching the bottom upwards in 3D.

[Anonymous]

Well Matthew, if I did not misunderstand your reply, stretching upward manually the bottom in 3D view will automatically push upward all the points above as stretching is limited by the reference level of the mesh… Having a bottom higher than the reference level was possible in old versions of ARCHICAD, but this does not solve Arcadia's problem.

[Arcadia]

Lifting the mesh up in 3D didn't help. Using Til's suggestion and realizing that project zero in my reference levels dialogue box should be 99m not 0 solved the problem for me although I had to go through and reassign the correct hieghts to all my mesh points again. This is the first time I have tried to model my mesh using 'real' hieghts as before I used assumed hieghts relative to the floor level but I now I know how to do it properly I can see it being so much easier. Thanks for the help.

[Anonymous]

Til wrote:
Well Matthew, if I did not misunderstand your reply, stretching upward manually the bottom in 3D view will automatically push upward all the points above as stretching is limited by the reference level of the mesh… Having a bottom higher than the reference level was possible in old versions of ARCHICAD, but this does not solve Arcadia's problem.

I thought I remembered doing this. I must be mistaken.

[Arcadia]

I can't understand why actually. Why can't we adjust the levels of points on the bottom of the mesh? I have had another situation where I would have liked to do this.

[David Maudlin]

The height of the skirt can be adjusted in the 3D Window, just select a node on the bottom, then the top row, second from left icon in the pet palette, you can use the "z" coordinate to input an exact height. If you drag the bottom higher than the top, then the entire Mesh will move up. (But if you want some weird results, input a negative height for the mesh skirt, in the Info Box you will see the bottom listed as higher than the top).

David

[Anonymous]

Thanks for checking David. I guess I'm not losing my mind after all (at least not yet).