Sunday, June 17, 2018

TUSCAN TRAVEL TALES

I had never heard of Anthony Bourdain until a few days ago, and I have nothing to say about suicide, but I have been reflecting on my travels, and I do think there is value in sharing stories and looking for meaning.

I have always regarded drawing as a tool for asking questions, probing deeper and paying closer attention.  So sketching over some of the photos from my trip to Volterra seemed like a good way to try out the new "all free" Autodesk Sketchbook.  I started on my phone (Note 8) and was thoroughly impressed with what can be achieved on such a small screen. The user interface on the Android version is excellent in my view, and I love the sPen.


My first drawing is very loose in style, kind of a pen & ink feel.  The perspective is quite dramatic, converging towards a distant point then disappearing round the corner to points unknown.  I was thinking in traditional "art" terms: composition, rhythm and balance; areas of flat surface contrasting with areas of detail.  These are very abstract ideas, but as I work I notice incidental details.  I become aware of the typical street lights projecting out from the wall on scroll brackets. 
Before the trip, I had started to think about the windows and even begun to make some Revit families.  There is a lot of variation, but also some extremely strong, persistent themes.  Ground floor windows are almost always treated quite differently from the upper stories.  The main factor seems to be security: sturdy bars forming a grid of squares or diamonds, or occasionally more elaborate scrolls and radial arrays.



Ground floor windows have solid shutters, opening inwards, secured from the inside.  By contrast, upper windows have louvred shutters that open out.  These are fascinating contraptions.  Some of the louvres are fixed, some enclosed in a secondary frame the hinges out like a flap when the shutter is in the closed position.  So you can have the shutters wide open with the glazing closed, or the glazing open with the shutters closed, but the flaps up to admit more light and air.  Or you can play with the permutations to suit the situation.

It's clear that many of the residents of Volterra live in apartments, so the window a point of contact with the outside world.  Domestic life spills out in the form of washing lines on pulleys and little rows of plant pots on the window sill.  How far does apartment life trace back? To medieval times, late Roman, early Etruscan?  Would it be possible to outline the evolution of urban housing in Tuscany over the centuries?



My second drawing was chosen for its dramatic pattern of light and shade.  I started with a simple boundary and areas of flat fill to represent deep shadow and sky.  Later on the flood fill accidentally picked up patches of darkness in the lower walls.  These two moves conspired to tilt the image towards a comic-book style, emphasised by the powder blue and yellow.  No shutters here? I guess the geometry of the tall narrow alley keeps the windows in shade most of the time anyway.  Is this a general rule, or a lonely coincidence?



Volterra gives the impression of being a single organism.  The palette of materials is restricted but quite rich.  Walls are often a wild and crazy blend of stone and brick, perhaps with patches of crumbling stucco, and accents of dressed stone.  Doors often come as a hinged pair, even where the opening is quite narrow.  I love the traditional blacksmith technique for locking a grid of bars together like threading cotton through the eye of a needle.



The mixture of stone and brick is sometimes a random effect over time as window openings are moved around, sometimes the calculated insertion of brick string courses and relieving arches giving structure to random rubble walling. It's not unusual for the lower courses to be dressed stone, with un-coursed rubble above.  It's difficult to know how much of this rich textural variation was meant to be seen and how much results from stucco falling off, or owners never quite finishing the job.



I'm not sure how to characterise my third drawing.  I used my iPad this time and it became a highly abstracted study in textures.  Once again I was attracted by the drama of the perspective.  The alleys are often bridged by arches, sometimes with linking rooms above, but here apparently structural buttresses, resisting internal thrust.  But why?  You can see a couple of rainwater pipes here, normally copper, descending from half-round gutters.  It seems to be normal practice for the downpipes to disappear inside the wall at ground floor.  Is this to protect them from damage?  Presumably they drop straight into an underground stormwater system.

Water collection and storage was surely crucial for a hill-top town.  There are public drinking troughs at low points just inside the city walls.  There are circular stone covers that surely give access to stormwater drains.  I first saw these in Florence, and there are lots of them in Volterra.  Sometimes you can see outflows from the edge of the street leading to barrel-vaulted brick drains.



"Roman bricks" to me are long, wide and shallow: half way between a brick and a tile perhaps.  Think Frank Lloyd Wright.  The standard size in Tuscany seems to be 250x120x55.  The interesting thing about this format is its flexibility.  You can use it for flooring and vaulting as well as in coursed walling.  Various kinds of vaulting are commonly used in ceilings, often plastered, but sometimes with the flat brick exposed.  How are these constructed?  You would assume that timber formwork is used, but how do you go about constructing an internal vaulted ceiling within an existing space?  It seemed to me that some shops and cafes had managed to do this, but how?  As a side note, there are coats of arms all over the city.  I wonder how many families maintain this tradition, or can interpret the symbolism.



I suppose you could set up a blood-circulation metaphor, where "Via" means Artery, flowing from gate to gate across the crown of the ridge, and lined with the Palazzi of the patrician class.  "Vicolo" then would translate to capillary, dispersing oxygen to the lower classes as they trickle down the slopes towards the perimeter wall.  But why are these dingy, crumbling alleyways so attractive, so tinged with romantic beauty?



Getting back to the windows...  I will get around to more Family Editor work in due course.  Meanwhile there are dozens of images to sift through and make sense of.  I'm fascinated by the ironmongery/window hardware.  What are all these items called.  There's the shutter stay (?) for holding open the flap, usually a rod bent into shape like a tent peg.  It slots into a series of holes in the shutter flap to hold it open at different angles.

The bottom hinges are commonly L shaped to hold the bottom rail at right angles to the hinge stile, in case the tenon joints should loosen up and the whole frame droop into a parallelogram.  Then there are the wall brackets that hold the shutters in a fully open position.  Flat steel bar built into the wall, with a spring clip hinged from the outer end.  What about the little catch that holds the flap in place when closed: two flat plates and a little rotating arm?  Very common also is what I guess must be a flag-pole holder.  So many things you can do by leaning out of one of these windows: hang out the washing, water the plants, adjust the flow of light and air, fly the flag.




My final drawing was done on the PC using a Wacom tablet.  You can tell by the sensitivity of the line and the level of detail.  This is San Felice, a chapel and a minor gate.  This image captures the feeling of a limitless horizon around the town: rolling arable farmland floating out in every direction.  Comparing the three formats/operating systems/pen technologies?  I still find the Apple pencil disappointing, but the iPad is a good compromise between phone and PC peripheral in terms of size and portability / ease of use.  I guess I will continue to use all three.




Down the hill to the right is the "Fonte di San Felice" part of the city water system that includes underground cisterns and at least one natural spring.  Lots of questions about how that network works (or worked).

We have so much point cloud data, mapping out the major arteries in three dimensions.  I've linked this into a massing model of the city, constructed in Revit.  This image is a camera view from that Revit file, with the point cloud isolated.  It shows two drinking troughs and an archway going under the road that circles the city just beyond the perimeter wall. Below are snaps of a stormwater outfall and one of the circular stone covers.



The massing model is colour coded, dividing the city into zones as an aid to understanding its structure.  I'm really enjoying the combination of this very abstract, representation of the city and the incredible detail of the reality capture data.  It's a potent combination for analytical studies.  To date my main focus has been to consolidate memories of a rich two-week experience and to build up my knowledge of the city, it's structure and urban texture.  But of course I'm also beginning to search for meaning, to make comparisons and to ask probing questions.




At some point I will look to connect this work with my studies of the Bank of England.  Tuscany has very strong historic connections to the economy of Britain.  Wool was the mainstay of British wealth for centuries, and the bankers and merchants of Florence played a key role in this trade.  There is a famous episode in Medieval history called the Revolt of the Ciompi where the wool workers rose up against the patricians and established their own government ... briefly.  One of the striking features of Volterra is the role that artists and craftsmen continue to play in the life of the city.  There is a continuity of urban life which is almost tangible: the alabaster workshops, metalworking and terracotta sculpture.



Reflecting on the last few images, I am also struck by a physical resemblance to the Bank of England: the jumble of irregular building masses crammed within an encircling screen wall, a palimpsest bearing the marks of historical evolution.
The BIM pencil strikes again.

Sunday, May 20, 2018

JUST SO STORIES

I think it's fair to say that churches are very prominent in the history of Western Architecture.  Clearly they are deeply loaded with symbolic meaning.  I was brought up a Christian, but the "plain meeting room" kind, and I've been an atheist for at least 45 years now, so what meaning would I find in a church building?  Why would I set about modeling and analysing a church? 



I can look at the technology, materials & structural forces.  We could think about response to climate (I guess, although that aspect is probably less relevant that in a dwelling) and of course we can look at aesthetics in a fairly abstract way (rhythm, proportions, symmetry) but without meaning it all falls a bit flat.  Music is much more interesting when it evokes an emotional response.



I carried out a series of studies of Hawksmoor's London churches some years ago, but that was handled at the Urban Design level and strongly influenced by my excitement about rediscovering the city that I first fell in love with as a student ... 45 years ago (again)  More recently I modelled on of John Soane's three London churches.  Here the motivation was to take on a Soane building that I might actually be able to finish (lol) and to compare different aspects of his style and design approach.

https://grevity.blogspot.ae/2014/11/six-of-best.html

https://grevity.blogspot.ae/2014/11/more-hawksmoor-churches.html

https://grevity.blogspot.ae/2014/12/wool-gathering.html




I've been modelling the church of San Giusto Nuovo in Volterra.  This time it was about doing something tangible with the point cloud and photogrammetry information that we acquired during the workshop I recently attended.  But of course, the more churches you model, the more you start to aske questions and make questions and as a human being it's pretty much impossible to avoid looking for "meaning".



This is the first time I have used a point cloud to inform my modeling.  It's been a wonderful experience, not perfect, but so much better than fumbling around with the kind of source material I usually start from. 



One little trick that I developed to combat the sluggish response when trying to model on top of a point cloud.  Let's say you are in an elevation or section view and you want to model a particular decorative element.  Take a reference dimension based on points that you have already established, then use the snipping tool to save a jpeg of the area in question.  Switch over to family editor using a suitable template.  Paste in the jpeg (I wish you could just paste into Revit from the clipboard) and scale it based on the reference dimension.  Now you can trace over the reference image without Revit trying to snap to individual points within the scan data, or struggle to regenerate the screen as you zoom in and out.



San Giusto appears to be the Italian version of Saint Justus, a fairly common name.  "James the just" comes to mind, "just" to prove that I have a residual biblical memory, and via this sentence, that words "speciate" into multiple branches of meaning, simply by being used.  "Ius" was a Latin word for legal right, it came to mean correct, or precise and you can perhaps see how that slipped sideways into "only".  "Just So" stories started off meaning exactly so, but by being applied to rather fanciful tales flipped its meaning so that "Justice" became "Fake News". Which I suppose is poetic justice. Words are slippery.



There are smaller scrolls to terminate buttress walls down the sides of the building.  These line up with the internal arches that divide the nave into three bays, before the crossing.  Once again the point cloud was a wonderful tool for fine tuning the size and shape, but less so for articulating the form itself.  The yellow stone used here is quite soft, so there's a good deal of erosion and patching up.  Captured Reality can be quite irregular.  I choose to model an idealised version of the church.  Purified or justified perhaps. 



So the aim is to capture the design intent, to evoke a scroll in you mind's eye.  The size and proportions will be very close, but in Revit the ramped end of the spiral is always going to be a bit of a nightmare.  So I will cheat.  The starting point is an extrusion, drawn in a side view and adjusted to match the scan. Then I add sweeps, picking the edges of the extrusion for my path and using a profile a bit like a turned baluster. 



I wasn't able to do this "all in one" so I split it into three sections which proved useful later on.  I've done something similar before with the Ionic capital.  You can add two cylinders then extend the edge curves so they disappear almost tangentially into the sides of those cylinders.  The result is quite convincing and your brain does the rest.



One of my goals for the workshop was to use photogrammetry to capture sculptural detail and embed this into a Revit family.  Recap photo was struggling a bit on site, probably down to the flaky internet, but Dave Dreffs took some of my efforts and converted them successfully.  Here are some of the source photos.  It's a coat of arms taken from the plinth of one of the side altars that line the nave of the church.  I am assuming this has to do with local patrician families displaying their piety/investing in the afterlife.



Recap photo stitches these up automatically and spits out a textured mesh.  It can be quite detailed and quite heavy.  In this case an obj file of around 100mb.  Dave also made a nice little video clip, which I think you can do in Recap Photo itself.  I've been a bit lazy about spending time in these apps to be honest.  Or to put it another way ... impatient to use the results within Revit and get on with analysing the building.

https://youtu.be/HGhXZdvzwJA

3d Studio Max will open the obj file.  I am a total novice here, but you can then go to Modifiers/Mesh Editing/Pro Optimiser.  This will allow you to decimate the mesh, basically reduce the face count.  You can also do this in Recap Photo, but you are going to use Max to convert to DXF anyway.  You need to be pretty drastic.  The DXF version we are using (2004) has a limit of about 32k vertices.

 

Next step, is a process I have described before where you can select all the edges and make them invisible.  If you don't do this the mesh is going to look really awful in Revit.  To put it another way, by hiding the edges in this mesh you can have edges switched on for normal Revit geometry without this shield turning into a black blob because of the thousands of visible edges.  Another workaround is to set the line colour for the mesh to a pale grey, but this is a poor second best.

https://grevity.blogspot.ae/2016/03/be-gone-sharp-edges.html

https://grevity.blogspot.ae/2017/07/kak-handed.html



Here is my mesh brought into the altar family.  The black edges really help to define the mouldings around the plinth, but the lack of edges within the coat of arms disguises the fact that is is actually a mesh of tiny little triangles.  Revit does actually create the occasional black edge where the geometry is strongly undercut, but this is a bit unpredictable and changes as you rotate the view angle.


Ultimately I made the coat of arms as a nested family and created another one that can be swapped out with a type parameter.  This is just a simple lozenge shape which is based on the reality at San Giusto.  Perhaps some of the entities sponsoring the altars didn't have a coat of arms, or maybe they were taking the economy route.


To get the coat of arms to show up nicely in a hidden line section view, you will need to add some symbolic lines.  The whole process is quite time consuming.  Minimum of twenty photos from different angles, process them all in Recap Photo, decimate the mesh, hide the edges and convert to dxf, embed in a family (scale to suit) set the material in object styles, add symbolic lines/masking regions to taste.



But if you want to model historic buildings like this in Revit it does add a layer of reality that is difficult to achieve any other way.  We've already talked about fooling the eye/brain.  To be honest, all drawing/modelling/artistic representation comes down to this.  Whether you are Michelangelo, or Marvel Comics ... you are using sleight of hand to trigger the brain's pattern recognition system into believing a "just-so" story.  Of course, Enscape helps


In the end you want to do "just enough" to convey the message you intend.  In this case it is a question of finding a balance between abstraction and reality that will allow us to ask useful questions about the building: how it is built, what it meant to the community that used it, how does it compare to say St Peter, Walworth built by John Soane a century or so later.  My initial interpretation of the bays was that the arches extended into cross-walls carrying beams that run lengthways along the nave.  But I think the span is too large and the continuity of the roof void impeded.  Who knows?  It would be wonderful to venture up into that space.



So I have reverted to a trusses above "shell vaults" interpretation.  We did see lots of examples of ceiling vaults built with the shallow flat bricks that predominate locally. Again, I would love to see Tuscan tradesmen constructing these vaults.  One of the advantages of building a model from scratch with software like Revit is that you can create it "as it used to be".  Whereas a point cloud just captures a moment in time with whatever alterations and clutter have accumulated over time. So I restored the high level windows along the aisle, on the assumption that they used to exist.  Another open question, and there are many more to be asked.


So that is my version of San Giusto, Volterra as it stands today.  I would love to explore some deeper questions.  I haven't mentioned the question of the bell tower which seems to rest partly on the edge of a vault, nor the fact that I have omitted the lean-to structures either side of the "east end".  These look to be later additions, but they could be altered versions of rooms that were there originally.  The church was designed in 1628 though for some reason not consecrated until 1775.  The style puzzles me a little.  It is often described as Neoclassical or Renaissance, which I take to be generic terms.  The date would put it in the Baroque period and it does strike me as a kind of very simple, "rustic" version of Baroque.  But those are discussions for another day. Much to be done.


Sunday, April 8, 2018

STILL WAITING

Too long between posts, and especially behind on reporting my Bank of England
work.  We've been plugging away steadily, but even with a three day weekend, time seems to run out before I can document the progress.

Waiting Room Court was due for an upgrade, including the loggia along the northern side.  Soane had a strong liking for processions of tall narrow arches.  We have come across this in his church at Walworth as well as the central corridor of the Board of Trade.  I think the loggia is one of his best variations on this theme.  The drama is heightened by the way it proceeds from the relative darkness of the Doric Portico, opens up into the courtyard, then closes up again.



In preparing this post I came to another of those "realisation moments" that make this work so addictive to me.  The paired, shallow, flat columns of the distinctive north façade of Waiting Room Court are not just one of Soane's mannerisms.  They are their because of his wish to combine an "enfilade" of arches down the length of the corridor while keeping the space open to the elements on the courtyard side.  On the internal side, the cross-walls that host the arches are framed by a pair of half-pilasters.  On the open side these half-pilasters wrap around to be expressed as those distinctive flat columns that make such an impression in Yerbury's record photos from c1930.


Another subtlety I quite enjoyed was the splitting of walls in section view to create the hint of an entablature resting on the pilasters.  Along with the two types of arches, come two arrangements of ceiling coffers, both quite elaborate and treated here as loadable Generic Model families.  The enscape3d image below was captured before creating the coffers families and the three images on the left record a developmental sequence, starting with an in-place extrusions, copy-pasted into a family template, then cut by voids.  Is this a Soane original design, or is it developed from a classical precedent?  Obviously stepped coffers, and oval coffers were not invented by Soane, but what about this combination.  I really don't know.  Perhaps someone will stumble across an answer.


It's important to remember that Waiting Room Court (WRC) is built at the junction of old and new.  Princes Street used to run diagonally across this space, until Soane straightened it on behalf of the Bank as it flexed its muscles over its former landlords the Grocers' Company, who owned the land where the loggia was built.  So the loggia represents the new regime: modern banking with shareholders and a board of directors, while the other 3 sides of the courtyard recall the older world of medieval guilds and hereditary occupations.  Whether consciously or not, Soane has expressed this transition in his architectural treatment.  And it's interesting to note that he maintains a balance between contrast and harmony.  The courtyard holds together despite the rather different elevational treatment of the loggia.  All four sides stand on the same rusticated base.  Britain managed its transition into modernity without the cataclysm of the French Revolution partly due to the moderating influence of the Bank of England.



It's almost embarrassing how easy it is to capture compelling images with Enscape3d.  Here you can see the two types of coffer and the two different arches.  Also on view is the higher ceiling in the central bay, which is still very crudely modelled.  I'm tempted to add some top lighting here, although the survey drawings suggest blind recesses rather than windows.  This is not definitive of course.  The survey also shows the narrow end bays as open, which is a change that was made later on by another architect.  Certainly it would be unusual for Soane to create this additional height without lighting it.  This was done before gas lighting remember. 



The WRC itself was long overdue for a facelift.  Window families were just simple openings in some cases.  The main cornice had been created as a wall sweep and kept coming apart at the corners.  Replaced with an in-place sweep. The basement story needed to be treated as a rusticated base so we made a start on that by fleshing out the large half-round windows.



It's clear that several of the windows are "blind" because they back on to the junction between rooms or, in one case overlap between the top corner of a vault and the ceiling void above.  To achieve the blind window effect, replace the cut opening with a void extrusion.



As the rustication proceeded it seemed appropriate to update the render appearance for the walls to a more stone-like material.  This led to some quite dramatic images, but ultimately the stone finish is not correct for the internal spaces, so I have begun to set up new wall types



All the same it does feel good to have additional richness in terms of material finishes.  We will have to look for other ways to achieve this moving forwards, maybe it will come in features like the fireplaces, and perhaps we can start to add furniture, carpets, etc. to bring spaces to life.

An interesting question that arises in my brain from time to time.  Why spend time creating seductive, dramatic images?  How does that relate to "historically accurate modelling" on the scale of aims and objectives?  My answer usually is: this is all about understanding, finding meaning in our built past.  Understanding doesn't always arise through conscious reasoning.  In fact the evidence is that our opinions are formed at a subconscious level and subjected to conscious reflection after the fact.



So I would say that it's a cyclical process, like anything in the creative realm you pour energy into an activity then stand back and review.  Emotions and reason intermingle to drive the whole thing forward.  Insights often come apparently from nowhere: those Eureka moments.  So while you are "waiting" for the next blinding insight, why not feed the brain with stimulating visual fodder?