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Drawing hardscape with a rainwater run-off gradient - help!

Is there a way of using the hardscape tool to draw a surface which has a rainwater run-off gradient?

I tried looking at "3D reshape", but couldn't see anything obvious (I'm using VW 2008).

The problem is that a "real world" patio of (say) 5m width with a 1:75 fall would have a Z plane difference of 67mm. between the two edges OK this might not look "wrong" in a 3D view, but if the patio edge is a retaining wall and steps to a diffferent level, the construction cross-sections would be wrong and the dimensioning would be wrong.

The only way I can see to represent it is a NURBS surface, but this seems a really difficult / tedious way to address the issue - though I guess it would allow a 2-way fall to be modelled!

Steve R.

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Tags: Hardscape, gradient

Replies to This Discussion

Permalink Reply by Jonathan Pickup on November 20, 2009 at 12:58pm

i can only think of a workaround. Use pads to create the 3D parts, and use the hardscape for 2d only.

Permalink Reply by Tamsin Slatter on April 7, 2010 at 1:08pm

Steve

A good workaround here is to use the Roof Face command under the Landmark/AEC menu. This will allow you to create the fall you want but also get a good 2D display. You won't be able to show any edging materials with this method, but you could always use Walls to do this. Are you working with a terrain model? If so, create a pad with the correct slope value beneath the roof face "hardscape" to modify the site as required.

All the best
T

Permalink Reply by Steve Rice on June 11, 2010 at 7:10am

Hi Tamsin - thanks for this advice, and sorry I took so long to try it & reply!

Roof face works great!

I like being able to use any polygon shape, and being able to have the "roof" axis on a diagonal, so the whole of the "patio" can be on a tilted plane, giving a 2-way fall. It's also easy to make "cut-outs" in the roof face/patio - e.g. inset planting beds / water features / etc. By having several distinct roof faces with differing axes, I can now fairly easily model hardscape with correct surface water run-off falls to embedded channels, slot-drains or gullies. As you say, edging detail could be included by using a wall, but in order to get the same fall(s), I used the following:

1) Duplicate (in-place) the roof face / patio;
2) Modify - edit group the duplicate. Use the offset tool to "shrink" the polygon by the width of the edging - e.g. 200mm for a pavior - then exit group;
3) Select the larger and smaller roof face objects and use modify - clip surface;
4) The edging is now a second roof face but with the exact same shape, slope and z coordinates - it can be moved to a different class and further edited - e.g. to change its z-axis and thickness values (as a 50mm thick pavior is thicker than a 35mm thick Sandstone slab!)

Using the roof face also allows objects (e.g. table & chairs or humans) to be positioned on it, just like a hardscape would - something which my previous experiments using "very low, but very thick walls, adjusted using the 3D reshape tool" didn't allow!

I've attached an image of a simple example - didn't bother with texturing!

Thanks ... Steve R.