La prima puntata di SuperQuark della stagione 2017 è stata per noi una splendida occasione per aiutare a spiegare la tecnica fotogrammetrica di modellazione 3D e parlare di alcuni progetti di Cultural Heritage che abbiamo realizzato sfruttando questa tecnica.
In particolare abbiamo avuto modo di mostrare il progetto Isabella d’Este Virtual Studiolo.
Siamo molto contenti che la regia abbia scelto di coinvolgerci e che i giovani del laboratorio abbiano avuto l’occasione di mostrarsi nelle loro attività.
A perpetua memoria della bella presentazione fatta da Daniele e Luigi sulla realizzazione del concept demo video dedicato al virtual studiolo di Isabella d’Este, ecco il video condiviso dalla Blender Foundation
In this tutorial you are going to discover how to:
use fluids for dropping sealing wax
manually animate the spreading of the wax
use modifiers to impress a seal
define a realistic wax effect
Are you longing to get a result similar to the one presented in our demo video?
If we have managed to put up a good tutorial, you should be able to. Otherwise, contact us, and we will apologize for our poor communication skills.
Let us start.
First of all we created 3 UV spheres with different size and shape. One of the spheres was a little bit sculpted in order to modify its shape. The fluid coming from the spheres is initialized with three different starting speeds. The first and second wax drops move a little bit up, along the Z, before going down. In this way, we simulate a diachronic fall.
(A possible solution with a movement of the spheres in the domain was discarded as deemed unsatisfactory)
The plane is set as an obstacle. Its parameters are shown in the image (no slip). Both plane and spheres are Fluid (physics)
In order to simulate the wax density: base 2, exponent 3 in the viscosity parameters
For avoiding excessive spreading of the wax on the paper: Slip type -> no slip
To obtain a Slow motion effect: Speed 0.3
After several attempts we discovered that the parameter that suited us better for the Real World Size is 0.4 meters for the domain
To obtain a wax-style fluid Smoothing is set at 4
Bake a test simulation with a final resolution of 100-150 to see if there is something wrong. When you get a first result of the wax spreading correctly, bake the definitive version with a final resolution of 200-400.
Now that the wax is on the paper we want to smooth it even more, so we add a Corrective smooth modifier with parameters:
Factor between 1-1.2
Repeat at 50-80
When the simulation slows down, stop the animation (for example at frame 220) and duplicate the wax object. Press “Esc” for keeping it still and put it on another layer. To fix the copy and transform it into a mesh with that shape, apply the Fluidsim modifier.
For your convenience, re-name the two objects. We named the first one wax-sim and the second one wax-fixed.
Swapping the two wax objects
In order to swap the two objects during the animation, you have to animate the visibility.
Place yourself where you stopped the animation earlier. In our case, at frame 220.
Select object n. 1 (wax-sim).
In the outliner, animate visibility and rendering as enabled by placing the mouse cursor on each relative symbol and clicking on the “i” key.
Go to frame 221, disable them and animate as before (mouse cursor on and “i” key)
In order to show the second object (wax-fixed):
Go back to frame 220
Animate visibility and rendering as disabled.
At frame 221 enable and animate them. That is, make the opposite of the previous steps
Here is a GIF presenting the entire process for swapping the objects.
Refinements with Shape keys
For concealing the swap between a moving fluid object and the static wax one we used a couple of shape keys, a suitable tool for giving the final touch to the shape of the wax drop.
In order to work on the real mesh, the corrective smooth modifier is temporarily reduced from a factor of 1.2 to a factor of 0.01.
Hence, for smoothing by hand the surface and give a faint persistency of the spreading effect, two shape keys are created: smooth and grow.
Shape key smooth – for reducing the roughness of the surface without the use of the Corrective smooth modifier, we can use sculpt with the smooth brush.
Shape key grow – by using the sculpt tool the shape of the drop is a little bit enlarged and rounded off, for simulating the last phases of the spreading of the wax on the surface. For this aim, a wide enough grab brush will do the job.
Once this phase is concluded, we can take the corrective smooth modifier back to a factor of 1.2.
Animation of shape keys
It is time to animate the two shape keys in opposition to the corrective smooth modifier by gradually reducing the modifier(from 1.2 to 0.01) while increasing the shape keys grow and smooth (from 0 to 1).
This animation starts for us at frame 221
The animation of the shape key grow will last longer in comparison to the transition occurring between corrective smooth and shape key smooth.
When the transition of the corrective smooth is concluded, by reaching a factor of 0.01, the displace animation starts, in the picture from frame 271 to 310.
Impress the seal
For the displacement animation we activate 3 modifiers:
Subdivision surface (with levels as shown in the image);
Displace (important is the creation of an empty for correctly positioning the seal in the displace);
Subdivision surface (again).
At this point, animate the strength from 0 to 0,025.
Be careful with the Subdivison levels in the view because the mesh will be very heavy.
The texture is in black/white and the levels of gray define the height of the displacement relief.
For simulating the shift of the wax due to the impression of the seal, these levels are higher (i.e. whiter) near the border of the seal and soften towards a slightly darker shade of gray in the area beyond.
In the image, the configuration for the shader “wax”:
Il VisitLab è felice di introdurre i lettori del suo blog ad un nuovo progetto. Lasciamoci guidare in questo viaggio dalle parole di Deanna Shemek, capo progetto di Isabella d’Este Virtual Studiolo:
My visit to Cineca last month was really amazing. I’m from the University of California, Santa Cruz, and I went to Cineca’s Visit Lab in March to meet with a team of super-smart people there. Together we are building an immersive, virtual recreation of the famous Renaissance studiolo of Isabella d’Este.
Isabella d’Este, Tiziano, 1534-1536, Olio su tela, 102×64 cm, Kunsthistorisches Museum, Vienna
Isabella led an active life, especially for a woman of the sixteenth century. She married Francesco II Gonzaga, marchese of Mantua in 1490 and governed their city state with him. In her spare time, she commissioned and played music by important composers like Tromboncino and Cara. She ran a perfume pharmacy and grew her own flowers for those products. She collected art and antiquities, and showed them off in her special space, her camerini, also known as the studiolo and grotta. A lot of her paintings, sculptures, and other beautiful things are now in museums around the world, and we are working together to put as much of it as we can back together, so people around the world can visit the studiolo virtually.
This is Giovanni, the film director at Visit Lab. He has a lot of good ideas.
We got right to work, talking about our plans. How can we tell people about the Virtual Studiolo in a film of just 2 minutes?
Then we went into Cineca’s virtual theater to look at the models they have made so far. This is Mission Control. Antonella and Daniele set up the model for me to look at.
Maria Chiara joined us, and we took a look at the photogrammetry model they have made of the real Studiolo, in the Palazzo Ducale of Mantua.
There are lots of working phases in the process (mainly involving Blender)
Wow, they can even turn the studiolo inside-out!
We talked about our next steps.
We like it, so far! I can’t wait to see what comes next.
And before I go, I get to meet the big guys: This is the supercomputer hardware room. I’m standing next to Fermi
Maybe these were made in California, but the Virtual Studiolo will be Made in Italy!
Thanks, Antonella, Maria Chiara, Daniele, and Giovanni!
Grazie a te, Deanna.
Continuate a seguirci per altri aggiornamenti sul progetto.