topic Re: ArchiCAD 12+? in Modeling

!Restored: ArchiCAD 12+?

Anonymous — Thu, 24 May 2007 02:56:45 GMT

As the debate on the relative merits of ArchiCAD 11 rolls on, and we all digest what still remains to be addressed, there are obviously numerous issues that remain unresolved.

Some we have learned to live with, and find workarounds for. There are others that I believe are much more fundamental.
One of those is how ArchiCAD deals with curved surfaces.
Many people fail to understand that in ArchiCAD, curved surfaces become facetted in Views AND 2D section and elevation windows. It is like turning a vectorial line drawing into a bitmap - it might look OK but try doing anything that requires accuracy (like, for instance, working drawings!) and you are in trouble....

I have prepared a PDF (refer attached file) complete with an example explaining the problem.

Please consider lobbying GS as I reckon this will become more & more of a problem...

Re: ArchiCAD 12+?

Rafal SLEK — Thu, 24 May 2007 07:40:44 GMT

Are You sure that Wishlist isn't better place for Your thread?

Re: ArchiCAD 12+?

Wokka — Thu, 24 May 2007 07:57:23 GMT

Hey Robert,
I feel your pain!
I've actually added this to the wish list for the last 5 releases, ever since R5 had real curved walls!
We use a lot of colorbond in our designs, often with curved roof elements and just the annoying facets on 1:100 elevations is bad enough, let alone construction documentation.
I'm resorting to using special profiles just to get the 3D looking right.

Re: ArchiCAD 12+?

Rob — Thu, 24 May 2007 08:38:36 GMT

Administrator guys, could you please move this topic into the wishes section just keep it more and logically accessible to the wider audience I suppose...
Anyway Rob, I fully agree with your comments as the current curved roof tool is a dinosaur in terms of actual usability. it's almost ridiculous...

Re: ArchiCAD 12+?

stefan — Fri, 25 May 2007 12:22:55 GMT

While I don't often use curved surfaces, I do agree with a commitment to a more robust geometrical core in ArchiCAD. Real curved (or planar) roofs, walls and floors, which correctly intersect and produce reliable sections are very important for the Virtual Building.

Now AC11 is released I hope the programmers have a short (well-deserved) break and the project management team focuses on improving the Virtual Building before all else. I still have major complaints about intersections between multilayered floors with multilayered walls, which is also fundamental, IMHO.

Re: ArchiCAD 12+?

Djordje — Sat, 26 May 2007 09:41:40 GMT

No need to move the topic to Wishlist. This is the place for all general discussions about Archicad.

Re: ArchiCAD 12+?

Anonymous — Mon, 28 May 2007 08:15:44 GMT

From your document, you note that Revit may better represent curved surfaces. I should note that even if Revit does, it doesn't necessarily make the situation more usable. Snapping to these objects in many cases (when the cut plane is not parallel to the object's curvature) is impossible. Dimension references will not pick up the object at all. A short 2D line has to be drawn for the dimension to snap to.

Re: ArchiCAD 12+?

stefan — Tue, 29 May 2007 07:56:59 GMT

Having real curved surfaces is one thing, making them act as real building elements (e.g. placing windows, deriving schedules, properly dimensioning them) is a whole other problem.

The visualization is almost there (with issues), but the other aspects, essential for BIM, are far from being realized. But I don't think that there is any software for BIM, at the moment, that does this correctly. You might try CATIA/Digital Project, but I assume that what you gain in surface capabilities will be lost on other aspects: drafting and correct construction documentation? I don't know...

Re: ArchiCAD 12+?

Anonymous — Sun, 02 Mar 2008 10:25:01 GMT

Clean 2d is a major need . Sometime is difficult to have both 3d and 2d clean in the same project. For example the shaded + shadow elevation for circular columns in AC11 is better than older versions but can be better maby using a fill like Linear gradient fill for cilinders or Circular gradient fill for spheres optimized for 2d representation .

Re: ArchiCAD 12+?

Anonymous — Sun, 02 Mar 2008 15:18:29 GMT

The real source of the problem is translation from mathematical curve to something that your graphic card can understand. Even Revit is faceting. Create a curved object and zoom very close and you will observe it. In Autocad it is even worse, because you have to use regen after zooming. Even in Rhino that is nurbs modeling software you have parameters that define how the objects will be faceted in 3D window. We probably should complain more to the graphic card producers to incorporate accelerated display of mathematical curves and surfaces.

Going back to the problem you can typically resolve it by splitting object to the smaller pieces. And as I remember even if your display shows faceted wall that differs from the real curve, the snapping will lead to there actual curve, so there should be no problem with accuracy.

Re: ArchiCAD 12+?

stefan — Mon, 03 Mar 2008 13:51:02 GMT

Miki wrote:
The real source of the problem is translation from mathematical curve to something that your graphic card can understand.[...]

The viewport display is just a representation, which indeed uses the Graphics card for improved performance. The analytic display in ArchiCAD (the hidden line display in the "internal engine") uses the real lines and curves and this uses only the CPU. Even though it is not possible to display the "real" surfaces in a program such as Rhino, they handle the full geometric complexity underneath for geometric operations.

In fact, we see the clean surfaces only through some representational approximation 😉