1st parametric AEC CAD

[Rob]

I just would like to know (curiosity) why Revit claims to be the 1st parametric AEC CAD on the market since 1997. Is that true? or it's just another misleading marketing slogan? What about GDL then, wasn't it parametric before AC 6 got released?

[Scott Davis]

Revit claimed to be the first FULLY parametric building modeler on the market. Revit's parametric abilities are bi-directional, and the change made to an object is automatically propagated throught the entire model. Make a change to the plan, and all sections, elevations, RCPs, schedules, etc., automatically update. Make a change to the schedule, and the entire model updates. No need to manually initiate an update. In this sense, Revit was the first fully parametric building modeler. No one else had the ability to keep a set of documents fully coordinated as changes occured.

[Rob]

oh, I have not noticed 'fully' word (not being sarcastic), that's why I got confused...
thanks anyway

[Eduardo Rolon]

And the differences with ArchiCAD are?

Oh I get it, Revit is the first one since '97 and that is different from being the first one since '82

[Rob]

to avoid misunderstandings which could be easily drawn from my first question I should say I have asked because of my dispute about CAD history article on the net, which states Revit's claim. Personally I have not worked with Revit and I have not monitored its development over years so that is why I got little bit surprised....

ejrolon, take it easy and have a lovely day

[Scott Davis]

ejrolon wrote:
And the differences with ArchiCAD are?

Oh I get it, Revit is the first one since '97 and that is different from being the first one since '82

Is ArchiCAD fully paramertic? Can you make a change and have it propagate through the entire model and sets of drawings automatically? Can you change an item in a schedule and have it update the model? Can you make a change from a sheet?

[Karl Ottenstein]

Scott wrote:
Is ArchiCAD fully paramertic? Can you make a change and have it propagate through the entire model and sets of drawings automatically? Can you change an item in a schedule and have it update the model? Can you make a change from a sheet?

Seemingly so (whatever 'fully' might mean?); yes; yes; yes. 😉

Some updates can be chosen to be done manually. A few (other than the above questions) have to be done manually: zone updates, placed schedule updates, detail windows...

Karl

[Rob]

dear Scott,

surprisingly you can, what's more you can programme fully parametric object with unlimited number of parameters and you can use system variables as well (read only mode). So, for example you can query system which storey you are on, where is the north etc....
Archicad is basically huge relational database with its own language GDL which has its own programmer interface within Archicad itself. So being a little bit agile in GDL programming you can cover really huge area and customisation (to the really high degree). However you can unlink particular sections/elevations and so on to get just 2d lines if you wish.
But you must know that... it has been built in AC from early 90-ties (to my knowledge)!?

[Anonymous]

Scott wrote:
Is ArchiCAD fully paramertic? Can you make a change and have it propagate through the entire model and sets of drawings automatically?

Personally, I prefer to have the changes propagate only when I want them to. This has always been my primary reservation about Revit. How this difference makes Revit more fully parametric than ArchiCAD escapes me. The claim to be the first fully parametric AEC modeler seems a bit like being the first left handed person to fly solo across the Atlantic.

Don't get me wrong. I think Revit is a very interesting product. The last time I used it was about 3-4 years ago though; maybe I should look into getting a new demo version.

[stefan]

Before you shoot on the claims from Revit, beware that the definition of "fully parametric" is not a very objective one. There is no plain and clear definition of what this is supposed to mean.

In a certain way, changing a cell in Excel and then causing the whole spreadsheet to update and trigger all kinds of VBA-macro's can also be called parametric (if you limit your modifications to the cells that are allowed).

That said, I think both ArchiCAD and Revit can more or less fullfill this claim, although not in the same way. There are many differences between the two of them.