Wednesday, October 24, 2012


Jack Milburn, my first grandchild, was born yesterday in Graz, Austria.  The tomato stalk was a query I received a week or so ago.

I'm going to explain a couple of techniques a bit more carefully and in the process make some more "Edible Plant Objects", modify my "Bean Pod Hand" and further refine the "Halloween Face Assembly"

So first of all the "Centre Pole" trick.  My tomatoes are based on 5 rectangular rigs configured into a radial array.  Check out the picture.  The key to keeping this relatively simple is the centre pole.  All 5 rigs share the same centre pole (a vertical reference line locked to the centre of the family)

This allows everything to scale up and down under the control of a master scale factor.  But within the rigs, I have great freedom to vary the shape of the curves that control the 5 curve lobes of my vegetable.  There are no nested "profile" families involved here.  The tomato consists of 5 curved surfaces.  Each surface is defined by 3 open-ended curves.

The tomato stalk uses a different approach, basically the one I used last year for my Doric Pumpkin.  It's a vertical stack of closed profiles.  The profiles are all instances of the same nested family.  Each profile has an offset (Height) parameter & a radius parameter.  One of them has been pushed off-centre & given a slight twist.  A random intervention.

Time to do some work.  I want to take the wonky tomato and convert it into a mushroom cap.  First I dissolved all the surfaces, then I needed to isolate each of the 5 profiles, one by one.  That's pretty easy: view cube into a top view, make a window around what you want, use the sunglasses to isolate. 

I have made my rigs wider and flatter, as befits a mushroom.  This causes the original curves to bulge out rather alarmingly. No matter, I am going to rebuild them into two simpler curves meeting at a point.  Plenty of patient point re-hosting ensues.

Having done all that 5 times over, I can select curves, (3 at a time) and "create form" them into surfaces.  Separate surfaces for top and bottom so I can use different colour materials.  It definitely looks like a mushroom so  I am a happy chappy.

And what are these mushrooms for ?  Lips of course.  Which lips ?  Quite right.  Witch lips indeed.

Pushing my head "sub-assembly" back into the main model, I can make a few more tweaks.  Reverse one of the avocado eyes to get the sideways glance.  Play around with the eyebrows, hunch up the shoulder blades.  Need some teeth though.

Teeth had better be pips.  Could be pumpkin seeds, grapefruit pips, who knows ?  This has to be a stack of closed profiles.  Tried to be too clever at first & came up with a profile that wouldn't join up smoothly.  So I simplified.  Still can't quite predict when I'm gonna hit one of these "can't make form" issues.  I guess it means I'm pushing the boundaries a bit.

Nice toothy grin, more fiddling with the eyes & brows.  Facial expressions are pretty tricky.  Our subconsciouses are so good at picking up every subtle nuance.  Conscious brain is left standing.  Squint your eyes, go make a cup of tea, ask someone else.  It's coming on though.

By the way, the teeth are fully scaleable.  All the widths & breadths & heights link back to a single scale parameter.  Could have built in more variability, but I think a simple change of size is enough.  The pic below catches me in the act of filling out the formula fields ... 2 down, 7 to go.

I need the left hand to hold the basket.  So my bean-pod fingers should curl around more to form some kind of fist.  The pods themselves are nested inside a hand assembly, so copy and rename that (right hand, left hand seem good names)  Can rename the bean pod if you like, but it's safely wrapped up inside the hand so no big deal.  Ah but the magic of the rectangular scaleable rig !!!

All I need to do is rehost a view points and nudge them about, hey presto, curly fingers. 

OK so it's not a perfect fist, but it will do for now.

I'm getting close to the point where I can put the Snow White source image aside and do my own thing.  Or perhaps pay more heed to Arcimboldo.

So what else does it need ?  I'm thinking it's a bit bare.  Archimboldo's pictures are absolutely crammed with stuff.  Not sure I can get anywhere near that, but there is time to throw a few more vegetables at the canvas & see if they stick.



  1. Fantastic!

    Oh, and congratulations on the birth of your grandson!

  2. Legend! You should come and present this at RTC New Zealand May 2013

  3. hai,,,nice work,,, i am trying to model hemishpere adaptive component like bowl,,,,with thicknesss,,,,any suggestion,,,still i cant find the way to stretch the circular,,,,,


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