Wednesday, April 15, 2015


OK, this is a first for me.

I've never used Revit Server, nor has anyone in our office ... until now.  We suddenly find ourselves needing to do some work jointly with our UK office and have managed to get things basically working.  It's not a hugely demanding situation, but the connection speeds are not that great, and it takes a LONG time to open the file in the morning.  After that it gets better, but crashing is not too much fun.

So I'm just asking people out there if they would care to share a little experience and any hints they may have.  How serious are latency issues ?  Any dos and don'ts that are not in the documentation ?  (I'm guessing that the documentation is like most Revit documentation ... not quite perfect)

What are the alternatives, for a medium size practice that will continue to do most of it's work on a local network ?  When will C4R reach the Middle East ?  (not expecting an answer to that one, but I'd love to know)

Share your experience, point me to a link.  It's a genuine question.  We are stumbling into new territory.  Trying to get some input from our local reseller also, but it seems they also don't have much experience in this area. 

So that's it.  I've overheard people grumbling about Revit Server and I prefer not to fall over horrible latency issues and break my leg.  Forewarned is four-legged  (who said that recently)

No pictures, shock horror !

Wednesday, April 8, 2015


How I love misleading titles:-) 

The humble louvre, whether fixed or as a door, is a necessary evil in our designs.  I blame the engineers.  Seriously though, they are a classic case for the consideration of 2D v 3D.  What level of detail should we model?

My standard approach is to use a material which includes horizontal lines as a fill pattern.  This allows a single door family to serve for louvres, glazed aluminium or panelled wood.  It's lightweight and flexible, and via a bump map can even do tolerable service in rendered views ... from a distance.

Recently I had to represent a variety of louvre types in a set of design proposals.  I have a family that I've used for several years that uses an array of rectangular slats in a rectangular frame, so I decided to adapt this.  I should explain that architects with "modern" sensibilities tend to prefer the purity of rectangular slats for screens that proviced a measure of privacy sun protection.

The slats in this family are a nested component with linked parameters (Width, Height & Length)  So all I had to do was to modify the cross-section of this family.  My first attempts, I must admit were quickly cobbled together and required some trial and error when adjusting the parameters.  But they did the job at the time.

On reflection I came up with a plan for a louvre-slat with user-friendly parameters.  Nothing spectacular here, but I thought it was worth sharing.

We already have width & height parameters inherited from the rectangular slat.  The first thing I did was to add a diagonal in the form of a Reference Line.  The great thing about Reference Lines is that (unlike planes) they have ENDS which can be locked in place.  Just use ALIGN as you normally would when locking a line to a reference plane, then TAB through the possible selections until the end highlights.

The thickness of the louvre is then set out using the diagonal as a centre.  Load this back into the original screen family and it works fairly well: lots of parametric control and quite convincing, even from close up.

At first I was happy to use the existing Height parameter to control the angle of the louvre, but eventually I decided that an Angle parameter would be simpler to use.  This requires a bit of trigonometry.
50 years ago I learned the simple mnemonic "Tommy on a ship of his caught a Herring"  Evidence to the curious workings of the human mind that this has stayed with me ever since.  There have been times when many years past without me ever thinking of it, but when the need arises I can recall it instantly. 

I want "Height" to be calculated using "Width" and "Angle".  The relevant formula is Tangent = Opposite/Adjacent.  A bit of manipulation leads me to Height = Tan(A) * Width
I was quite proud of this, but of course you can't set the angle to zero.  Wouldn't it be nice to have a slat that could be either square or angled ?  So I developed a second version.  This time I didn't need the Reference Line and the calculations are slightly more complex (but still within the confines of the algebra I learnt as a 14 year old)

So now I have a slat component with 4 "user input" parameters and 2 calculated values that I tuck away under "Other".  In practice of course the user input values are driven by parameters in the screen family that the slat lives inside.

Hook everything up and we have a pretty flexible set-up.  It can look like a series of shelves, or louvred glazing, or an AC vent.

I've organised the parameters in groups to make it as user-friendly as possible.  There's only one thing missing really and thats a "Spacing" parameter to be used in the formula that calculates the number of slats.

I got an error with this that's been puzzling me for some time.  The message threw me off by talking about importing the correct table.

Eventually I realised that I had 3 types in the family and at least 1 of them had a zero value for "Spacing".  That would generate an infinite number of slats, hence the error message.  If only the message mentioned a zero value instead of asking me to change the formula or import a non-existent table.  Anyway, it won't catch me out next time.

So that's it.  Finishing with another rendered view of some of the families I made and pointing you to a link where you can download the basic screen family.  Hope you find it useful.

Download The Family


Monday, March 30, 2015


That will be the title of one of my presentations in Washington this July. 

I am very proud to have been accepted once again as a speaker at RTC_NA, the North American version of the premier Revit Conference, "by users, for users".  Really looking forward to spending time with old friends and new, visiting the capital city for the second time, and hanging out with my daughter Wendy both before and after.

This diagram that looks a bit like a mouldy growth, spreading across a cracked wall, is in fact a subway map of Washington DC, subjected to various digital distortions.  This is one way to generate irregular, seemingly organic effects via the hexadecimal rigidity of the mindless machines that dominate our modern lives.  My session will approach a similar topic from a different angle, using basic family editor techniques to conjure up an impression of the casual disorder that typifies vernacular buildings.  You are most welcome to join me.

You may have noticed that my blog has been sadly neglected for several weeks now.  We have been burning the midnight hours at GAJ, a sure sign that Dubai is starting to go somewhat bonkers again: projects coming out of our ears.  Intense work experiences generate new ideas and I continue to reflect and learn as I stumble along with BIM pencil in hand.  Hopefully I can find more time for digital sharing over the coming weeks and months.

Last weekend was a chance to do this, and to start working on my presentations.  But I was side-tracked as I leapt (metaphorically) out of bed on Friday morning, by an idea for the RTC logo.  I don't want to be rude because I have great respect for the guys and gals behind this wonderful event, but IMHO the graphics are due for a makeover ... a little dated, don't you think ?

Anyway, it set me off on a little journey based on "why don't I do this in family editor ?".  I belong to that small band of fanatics who think that about almost anything.  I had in mind those Bauhaus style typefaces that are highly abstracted into parallel bands of straight lines and arcs.  Couldn't that be parametric ?

This is all sweeps.  Just 3 of them in fact.  The paths are constrained to reference planes, with a couple of reference LINES thrown in to keep the ends of the letter C to a 45 degree termination. 

I'm using a loaded profile so that the width of the letters can easily be varied in a coordinated manner.  The original motivation here is to be able to play with proportions parametrically, something that is harder to do using a graphics programme.
As a bonus I get the third dimension (which we will call thickness)  I don't intend to use this in my primary branding graphics.  I'm going for that very simple, flat look that dominates the world of touch and swipe right now.  But maybe it will come in handy here and there, used very sparingly.

Having said that, of course I couldn't stop myself playing around with the possibilities.  Lots of fun, and a good flexing exercise for my parametrics, but these are not graphic images I would actually consider using on letterheads, or presentation templates, or badges.

So let's get back to the flat logo.  I placed my family on a floor, just a square, drawn with the radius option checked.  Export this from a plan view and you have an image at whatever resolution you should choose and can now move on to conventional graphics programmes to play with colour combinations and add regular text.

I'm using the Calibri font that Microsoft commissioned in response to the accusation that Arial was boring (I think that's more or less what happened)  This has the advantage that almost everyone has it on their machine, it's simple and bold, but with quite a lot of subtle character.  My opinion, once again.  Feel free to differ.

I've given a passing nod to the current RTC colours.  Continuity is important in any re-branding exercise. And that's my contribution to the non-existent debate about the RTC logo.  I hope I haven't offended anyone by doing this in public.  It's just a bit of fun.  But personally speaking, I do think this is a much crisper, cleaner, web-friendly graphic style than the existing logotype.

Just for fun I mocked up a PowerPoint template.  Again this is just a personal opinion, but I dislike fussy graphics on these templates.  I suppose the idea is to make a boring series of bullet-point pages look a bit more exciting, but that's pretty weedy.  Shouldn't a speaker be able to come up with some compelling visual images that enhance his/her ideas ?  Isn't that what we want to focus our attention on, as opposed to some background graphic frills ?  So I prefer a simple, abstract template that isn't going to clash with the punchy images that a more imaginative presenter will surely put together.

At this point, I went back to Revit and punched in a couple of simple formulae to make the whole thing scale up and down based on a module.  I like to hide the formula-driven parameters down in the "Other" box so the end user doesn't get confused. 

Turns out that I needed one more constraint to get everything to scale properly.  I had neglected to give the letter C a labelled radius, which is of course just the existing "Module" parameter.

And not I have a family that can be copied around and varied with consumate ease.  Different sizes, different slenderness ratios, different thicknesses to brink colours to the front, or sent them to the back.  Once again, this is not a graphic image that I would use regularly, but it is nice to have a logo that is simple enough to handle this kind of manipulation.  You might want to generate a couple of these playful variations to use as accents at specific events or locations.

So that's it folks.  Once again, it's just a bit of fun.  I'm not trying to tread on the committee's toes or anything like that.  But it's been an interesting opportunity to explore and illustrate the capabilities of Family Editor in a slightly unusual context.

And remember, if you want to recharge your Revit batteries, there's no better way than registering for RTC, now available on 4 continents.  (Poor old mama Africa, left out once again)