Sunday, December 21, 2014


This was my presentation for AUX Dubai 2014 last week.  It's partially based on my rigs & profiles session at RTC Chicago, but with some new stuff ... mostly about using rigs in form-finding studies for high-rise towers.  Two slides to introduce myself.  Day job ...

Thursday, December 18, 2014


While preparing the previous post, I was motivated to dash off the basic modelling for a Starc 2 urinal.  Simplicity itself, which is the charm of this particular model.  I haven't tackled the symbolic views yet.  In fact this is almost able to stand up without symbolic work, but for the tendency of rounded edges to dissapear in orthographic views

So that's where I stand with my urinal collection.  A nice row of peas in a pod.  The image below shows the original cad versions alongside the natively modeled "improvements".  Still 2 or 3 to be tackled here, and strategies to be chosen: vanilla, point world, exploded CAD or CAD import.  Plus some cleaning up to be done in other cases.

A couple of posts ago I dodged the question of file sizes.  Time to address this now.  For some freeform shapes I have been modelling in Point World, exporting to SAT, rounding off edges, importing to Vanilla and exploding.  Looking at some of the SAT files, it is clear that rounding of sharp edges is an expensive operation, purely in terms of kilobytes.

Of course this doesn't necessarily translate into performance issues, or even larger project files.  Interestingly enough, 5mb worth of SAT files when collected into a single RFA end up at less than half that size.  Don't ask me how.

Received wisdom suggests that nesting, constraints and formulae impact performance more than megabytes.  This is good news for sanitaryware because although the geometry is often demanding, the shapes are fixed.  We might nest the taps and add a couple of visibility parameters but that shouldn't be a worry.

When I did the Puravida series, the nested taps on the bidet turned out to be very heavy when made in point world.  It was an interesting modelling exercise, but I managed something close enough in Vanilla at one twentieth of the size.  For a small item like this I think the nurbs version isn't really justified.  Cut your losses (or perhaps it's "cut the suit according to the cloth")

So I ended up with 4 Puravida families weighing in at around 1 to 2mb each.  That's complete with symbolic plans and elevations, material parameters and chrome fittings, but no connectors as yet.  Not being an MEP engineer I rarely get around to adding connectors to families. (my bad)

One more example of the unpredictability of file sizes.  I discovered that the downloaded SAT files for Happy D washbasins explode nicely inside Vanilla Revit.  Now the shapes may be fairly simple, but they do include a number of rounded edges.  My family has nested taps, visibility controls and 3 items of exploded geometry (1 basin plus 2 pedestals)  The whole thing weights in at less than 750 kb.

This family also includes symbolics in all 3 directions and for both types.  I don't know what software they used for the modelling, or even if that has any impact on the file size issue.  Would be interested to know if anyone has workflows for generating explodable 3d CAD more simply that my Point World methods.  You can see from the next image that exploding the geometry and adding symbolics results in a much better family. (but read Aaron's comment below)

Here is a view of my current Duravit collection.  I'm about ready to share this, and to invite people to contribute to the process of completing the collection.  Who knows, maybe we can even persuade Duravit to come to the party.

After all, other European manufacturers have started to make the effort.  Here are some families downloaded from the BIM object website.  Don't ask me why the thumbnails have a black background.  Maybe they were made my MEP engineers :-)

I decided to open these families up and take a good look.  This is all modeled directly in vanilla. Quite a tour-de-force in some ways.  But for my money, there is a certain amount of wasted effort.  I wouldn't have bothered with all that hidden detail around the back of the basins for example. 
There may come a time when BIM is used by the plumbers who install the fittings on site to help them visualise the whole process, but we are not there yet by a long way and if we do ever get there, I am not sure that they will be using the same objects that are used by the architects to position all the fittings in a 300 bedroom hotel (for example) Perhaps there will be a hyperlink in the family that takes you to a place in the cloud where all those finer installation details are modeled

Put more simply I am saying "let's model the parts that show in an interior rendering to an acceptable level, but don't get too carried away with unnecessary detail" which abbreviates to KISS.
So I simplified the basin considerably, cleaned the geometry up a bit so as to eliminate most of the seams, left out some of the finer detail on the bottle trap and generally felt like I had created a somewhat better family at the end of the day. 

I also added symbolics to the elevations and a masking region in plan view.  My approach to symbolics is to use them selectively.  With rectangular objects / sharp-edged objects I would tend to let the 3d geometry do the work, but if the shapes are "blobby" or there are too many edges/seams showing up in plan or elevation, symbolics are worth considering.  Sanitary ware is a classic case because the shapes are "blobby" and the sizes are fixed. (no struggling to get the 2d and 3d to flex in harmony)

Just out of interest, this family started at around 560kb, dropped to around 350 after I simplified (not immediately after, but 2 or 3 saves later)  Then it went back up to around 470 with the additional symbolics.  Lean and mean.

By the way, none of the above is intended as a criticism of BIM object or the manufacturer Jika, or whoever modeled the original family.  I think they have all made significant contributions to the global BIM effort and I enjoyed building on the platform they provided.  I hope they can also accept my suggestions in the positive spirit intended.

Almost ready to share my Duravit collection now.  Hope it's been worth the wait :-)


Sunday, December 14, 2014


About 9 months ago while working on my Urban Design presentation for RTC chicago I did a study of the Dessau Bauhaus in context.  Just a simple massing model of the famous building itself, and lots of schematic mapping out of the surrounding landscape.

For some reason my BIM pencil seems to like drawing maps.  Who am I to argue ?  But what an intense piece of history lurks beneath this landscape.  All these avant-garde artists and social dreamers cooking up their recipes while Adolf and his cronies sneak their way into power, perfecting propaganda as an art form along the way.

I'm not going to go any further into that right now, but while doing the research I stumbled across a Bauhaus Chess Set which struck me as a wonderfull little exercise in Vanilla parametrics.

I love the way this chess set is abstracted down to the simplest of geometric forms.  Classic Bauhaus design: break things apart, analyse them, rebuild from first principles.

My initial analysis suggested that I needed 3 families to cover all the pieces.  The Knight and the Bishop are basically one-offs.  They don't have to be, but I wanted to keep things fairly simple.  The other 4 pieces are covered by a family with 4 types and some visibility controls.

The plan is to make everything fully scalable.  Mostly this is done by equalisation constraints and simple formulae linking everything back to a module (usually the width parameter) For example in the Bishop family the thickness of the cross (T) is expressed as Width/3.

The knight is a big solid cube with two half-sized void cubes biting away diagonally opposite corners.  I guess this is an abstraction of the dog-leg manner in which knights move across the chess board.

The multi-purpose chess piece is very simple.  Notice the use of root 2 for the diagonally placed crown, and of course the visibility controls that I mentioned before.  And that completes the chess pieces.

Let's go ahead and place them on a board.  Lots of equality constraints here to make our 8x8 grid.  We need 4 material parameters: 2 for the board and 2 for the pieces.  Also 2 parameters will suffice to control all the pieces: one for the pawns, the other for all the rest.  Everything is now expressed as a fraction of the board width.

So of course the whole thing scales endlessly.  Well not quite.  We still have Revit's built in aversion for the extremely small and the ridiculously large.  It's optimised for buildings, stop complaining.  But I do feel able to complain about the lack of intelligent symbols for North Points and Scale Bars.  I once came up with a workaround for scale bars that uses ordinate dimensions referencing a detail component.  Maybe the logic is that drawing sheets will become obsolete so why waste the energy ?  I like drawings (you probably know that)  Whether we print them or not is another issue, but orthographic views arranged on sheets are very powerful means of communication.  You can't figure out how a building works just by doing a walkabout.

We have to get past this illusion that BIM is about making everything realistic.  The tension between realism and abstraction is as old as the hills and will be with us until we drive ourselves extinct.  The paradox of visualising reality on 2 dimensional surfaces has informed art for 30 thousand years.  Let's not fool ourselves with this nonsense about the end of history.  The end of history is armageddon.  Trust me, you don't want to go there.

So I'm happy to shift in and out of 1d/2d/3d space, exploring ideas, shuffling data, imagining impossible worlds.  Piet Mondrian took a journey around the time that the Bauhaus was built that has always blown my mind.  He started out with still lifes and landscapes that were partially abstracted, a bit like Cezanne.  Then he just went on flattening out and abstracting, form-finding in a way ... endless variations until all that remained was shape and colour.

Bauhaus students were also encouraged to simplify and abstract, but the logic now was to create forms that reflected the realities of industrial production.  These seem like trivial ideas now, but 90 years ago they were much more revolutionary than all the little consumer toys we label as "disruptive technology" today.  For that matter, the minimalism that Mr Jobs tried to copyright was really plagiarised from people like Mondriaan, Picasso, Gropius, Mies.  (It's OK I'm just being provocatively naughty)

But be careful what you wish for.  The 1920s and 1930s were stirring times.  Everything seemed to be changing.  Technology was something to love or hate, worship or despise.  Bauhaus masters like Johannes Itten reacted by immersing themselves in meditation and the mystical pull of ancient religions.  Dear old Adolf had a different plan in mind.   Technical solutions and aesthetic movements are wonderful in their way but hard economic realities and political turbulence have a knack for sweeping all that away overnight.  The Bauhaus was closed down.  Many creative minds fled Germany.  I have experienced hyper-inflation first hand.  It changes everything.  It drove me into the desert in search of gold.

Just a few reflections on History, Art, Politics ... and of course the game of chess.