The
texture and lighting of the elements in this piece added the final
flourish. The glossy bottle, the
smooth tequila, the shiny metal and the crackling ice set in a pure, dark
atmosphere set a somewhat seductive mood that the team achieved through
compositing several render passes.
Take a look below!
This wraps up our Liquid Simulation series for now. S&M has a lot of great work coming up which means more 'behind the scenes' soon. Watch this space!
Having
recently finished simulating the surging dam and its conglomeration of splashes
for Mountain Dew, the work for Hornitos seemed almost easy. However, creating the smooth, sultry
flow of tequila presented its own challenges.
Taking
the physically accurate model of the Hornitos bottle seen in the previous post,
the team filled it with fluid particles.
Because the shot required the tequila to pour from the tilted bottle,
the primary challenge was getting the pressure pockets of air to travel through
the neck of the bottle to convincingly create the ‘glugging’ of effect of
liquid pouring through a constricted pathway. Having ironed out this detail, the team applied the proper
viscosity to the liquid and then subjected it to other physical properties
including gravity and noise to give it believable flow and movement.
Cascading
across the embossed, channeled surface, the liquid needed to feel light and
delicate. Because the shot was
quite close up, the spacing of the particles became an issue as, at that close
viewing range, the particles were too far apart to be construed as a proper viscous
liquid. To ameliorate this issue,
the team multiplied the resolution of the particles by a factor of 20 helping
them achieve a more convincing result.
This
shot of the tequila filling in the horns was the most complex of the entire
spot. To accomplish the desired
aesthetic with proper splashes, the team composed the main fluid with several
smaller simulations. This allowed
them to more easily tweak various locations of the fluid. The simulation was run at a higher
frame rate than the rest of the spot, essentially slowing the simulation to allow
for greater control over the splashes.
The simulated particles then had to be pushed back the proper frame
rate; NextLimit’s new particle retiming tool within RealFlow became
indispensible in this situation. Once
the main simulation was complete, the team continued to introduce new fluid
systems to fill in the gaps within the horns.
After
modeling all of the elements and perfecting the liquid simulation, the last
step in creating this spot was lighting and rendering. Check back tomorrow for the last post!
Before approaching the tequila simulation, the team first needed to create the rest of the elements in the spot: the Hornitos Tequila bottle, the
grooved surface through which the liquid cascades and lastly the icy horns that
fill up with the flowing tequila. These pieces were necessary to complete the simulation and would also be featured in the final piece.
The first and easiest element for the team
was the Hornitos Tequila Bottle. Seen grayscale and partly textured here, it was eventually properly textured, lit and rendered to create a photoreal bottle.
Next came furrowed surface over which the tequila would flow. With the embossed text, "double distilled", and the shallow grooves, these elements added points of interest to the visual as they would interrupt the smooth flow of the tequila simulation. Meant to be a shiny metallic surface, the team also included
various knicks and grooves along the channels to give the element a slightly
aged, more compelling feel.
Most engaging for the team in terms of modeling was to create
was the set of icy horns that fill with the pouring tequila. Dictating a more organic aesthetic,
these horns were sculpted using MudBox.
This allowed the team to more easily form the various imperfections illustrative of actual ice. Of course it would take the proper texture and lighting to
fully achieve realism, but that will be approached in a later post.
With all the CG elements created, the next
challenge was going into RealFlow to simulate the flow of the tequila. Check back tomorrow for more on the tequila simulation process!
To showcase the purity of Hornitos
Tequila, this spot endeavored to set a pure but sultry atmosphere. In a
dark void, the tequila pours slowly from the bottle to cascade across a surface
embossed with lettering touting the spirits’ assets. We follow the liquid
as it spills across crackling ice in which more of the tequilas’ qualities are
engraved. The spot ends with the liquid pouring headlong into a pool
topped by the Hornitos logo. The mood needed to be slow, deliberate and
provocative. The final piece remained true to this brief throughout being
story boarded, pre-vized, animated, directed, lit and finished all in house at
Smoke and Mirrors NY. Every part of this spot is completely CG generated, from
metal to ice, bottle to liquid.
Given the voice-over script and a few
inspiration images, the SMNY team set to work concepting their ideas for the
piece, initially devising each shot using animated sketches. Having established various shots,
the team then combined their sketches of the proposed flow of tequila with grey
scale 3D elements to nail down the look and feel of the fluid motions in the
spot.
Having solidly pre-vized the spot, the
next step was to create the remaining CG elements in the spot as well as
perform the liquid simulation as depicted in the boardomatic sketches. Check back tomorrow for more on that!
Creating a flow of such magnitude at the scale of a dam was
not without it’s trial and error!
Working in RealFlow, the team was faced with reigning in calculations
and numerical values of the real physical properties of laminar and turbulent
flow. Setting up scenes to
simulate overnight, the team often found that one small error, such as a
misplaced decimal or a slightly inflated value produced some disastrous effects! See below...one decimal out of place caused the simulation to explode water from all sides:
There are no mistakes though; only lessons! These ‘bloopers’ were just part of the R&D process and
ultimately helped the team gain a more in depth knowledge of the software and
the best way to control it.
The knowledge the team gained working on this spot came in
quite handy as, just as soon as Mountain Dew wrapped, the team set to work on
another liquids simulation piece for Hornitos Tequila. A much smaller scale, this piece had an
entirely different look and feel that presented its own unique challenges. Take a look at the spot below and check
this space tomorrow for more on how it was created!
After mastering the main flow of the dam, the team was ready
to attack all of the splashing elements that characterize the turbulent flow of
the surging water. The crux of the
simulation, these splash elements were actually comprised of several separate
fluid simulations that, when brought together, would create the overall effect
of crashing water.
various splash simulations and the script used to strip out excess particle
As was mentioned in the previous post, the final simulations
had to run at an extreme resolution in order to ensure that there was enough detail within the
splashes to create a realistic look to the flow. However, it was impossible to work at this level of detail
and then actually render within the 3D authoring tool.
To navigate this issue, the team wrote a bespoke script that would strip out the extraneous particles from the simulation while maintaining an aesthetically workable
resolution [see image above]. In
addition, they did a tremendous amount of R&D work to push
the limits of the system to determine how high they could set the particle
count and still finish simulating on schedule. As such, they were able to create a simulation with a
fairly high level of detail in the splashes. The three images below illustrate the level of detail visible at increasingly zoomed in distances. These images were taken of the particle clouds after the script had been run. Click on the images for a larger view.
zoomed out
zooming in closer
zooming closer still
Looking at the clip above, each colored box represents an
independent splash. These
splashes were created by the curvature and density of the primary fluid simulation down the dam. Particles were
emitted wherever details in the waviness or density of the main flow met specific criteria. In this case above, when the threshold for the density fell below a certain level, splashes occurred. In other words, the edges of the water happened where it met the
geometry of the dam.
splash simulations looking down the dam: each colored box represents an independent splash
splash simulations: alternative view of the various splashes interacting down the dam
Because each splash was composed of several fluid simulations, the
next challenge was usurping enough machine power to actually complete each
simulation.Working in Next
Limit’s RealFlow, the software’s IDOC (Independent Domain of Computation)
system was a incredible help as it allowed the team to complete different
elements of each splash simulation across multiple machines, thus allowing the team to have more time to research, develop and perfect the piece and also allowing them to complete the work on schedule.
As mentioned before, it took an incredible amount of R&D
to perfect the fluid simulations.Check back tomorrow to see a few of the ill-fated attempts that
eventually led the CG team to their completed work.
The Smoke & Mirrors CG team has been hard at work honing
their fluid simulation skills in the past few weeks, first with a complex spot
for Mountain Dew India featuring a gushing dam and then with a beautifully
smooth piece for Hornitos Tequila.
Simulating the frenetic surge of a large scale dam in RealFlow for
Mountain Dew was a welcome challenge for the CG team, and the research they
conducted to complete Mountain Dew helped them to quickly and easily nail the
simulations to finish the Hornitos piece.
There were two main challenges to simulating the dam flow: scale and resolution; Scale was the largest hurdle for the team to overcome. In order for the liquid to feel massive, an
accurate scale needed to be established early on for the particle simulations.
Had the real-world scale been ignored, the liquid would have felt like it was operating
in miniature. Working at the scale of a dam, however, created other challenges in terms of render time and resolution.
To accomplish realism at such a scale, the fluid simulation actually required a conglomeration of several smaller simulations: one to create the
main, massive flow of water down the dam and then several others to simulate
the various splashes that occurred in the waters’ journey down the slope.
Ironing out the main flow first, the team simulated this surge
without the other splashing elements using a grid domain. This helped to contain this specific
flow and allowed for faster and more predictable simulation.
The next hurdle the team encountered was resolution, aka how
dense could they simulate the particles and still finish the job on schedule.
Since it was concluded that they would be using mostly particle shading for the
foamy whitewater, the particle density needed to be extremely high - much
higher than the traditional mesh shading common to smaller liquid jobs. Some of the scenes clocked in at upwards of 25 million particles. For purposes of testing however, simulations
were run at 1/50 of the final resolution that they were to be rendered. At this scale the team could get
a clear idea of the physical properties of the fluid that needed tweaking to
perfect the simulation without having to deal with the heavy renders.
Having tackled the main flow of water down the dam, the team then dove into R&D for the various splash simulations. This was a complex process that required work at a very high resolution....check this space tomorrow to see how the team achieved this!
