The list of effects in Horton Hears a Who! is surprising. Photo credit for all Horton images: Blue Sky Studios.

Of the animated features released so far in 2008, which one contained all of the following effects?

Water surface simulations, water drips, water spray, water jet, water falls, water splashes, bubbles, fountains, clouds, sawdust, rigid body sims, blowing leaves, cloth sims for flags, buntings, awnings & blankets. Boiling oil, fire/campfires, dust/debris. 3D fluid sims for fishbowls, melting snow, chemical spills, saliva/mucous, Novocaine, antacid liquid, popcorn kernels, shower heads.

Did you figure it out yet? If you didn't guess it with Novocaine and antacid liquid, here are some more effects from the same feature.

Tears, confetti, airborne clovers, Dandelion seeds, Demolition Dust, Dew Drops, Pollen, Soil debris, Soil Impressions, snow prints & snow powder & snow chunks. Flowing rivers, lasers, steam, smoke, mist, other volumetric effects. Mower clippings, sand, splinters, ice debris, distortion and cloud effects for the soundwaves.

If you guessed Horton Hears a Who!, you guessed right. Out of all those, which ones would you say were the most challenging to create?

According to Kirk Garfield, visual effects supervisor at Blue Sky Studios, "Some of the most challenging effects were in the opening sequence where we watch droplets of water collect on a leaf, drip and dislodge a seemingly massive spiky nut. This spiky nut then bounces down a tree and through a dandelion field.

"For the droplets collecting on the leaf, we used a combination of methods. The main droplets were animated by hand in Maya using spheres. The surrounding droplets that filled out the leaf were procedurally placed. We then used some of our in house post-particle editing scripts to combine the systems into one for meshing.

"Once the water droplets collect at the tip of the leaf, the droplet falls through the air until it collides with the spiky nut. The nut detaches from the branch, and then we witness the seed bounce down a tree and finally falling into a field of dandelions. The directors' wanted it to feel epic, so we cheated the physical forces a bit depending on the camera angle. The individual seed tufts dislodged from the core of the flower based on a custom set of rules written in both Maya (MEL) and CGI Studio."

Garfield added that since many of the effects are final animation dependent, pre-production was vital. "During pre-production is when we do most of our look development. By coming up with practical solutions to effects, we were able to provide more of it for the production. We also do a lot of housekeeping during pre-prod like refining our pipeline scripts (fxPipe) in preparation for the next production."

For Horton, the overall relationship between animation, layout and effects is important. Based on the script or storyboards, assumptions are made about what effects are needed for the film.

Meanwhile, the overall relationship between animation, layout and effects is once again important: "As early as the script or storyboards, I make assumptions about what effects are needed for the film," Garfield continued. "I collaborate most with story and layout to ensure what is requested is able to be produced with the current resources. We do a lot of planning with previs and layout to minimize the complexity of effects. We try to raise red flags before it is too late to basically avoid a crisis."

As for the interaction between characters and effects, they start by planning the collaboration in the early stages of production. "We often request temporary animation of a character or prop to help develop the work flow and or the look for the effect in question. Like any production, time is precious. Instead of waiting for final animation, we usually get in early and test things out, so by the time final animation is delivered, we have 75-90% of the work complete. In the final stages of effects production, we work very closely with materials and lighting to ensure everything looks good and is ready to hand off.

"Time and resource concerns were alleviated with proper planning, simplifications, and creative workarounds. It was imperative that we work close with the departments up and down stream of us. Horton was a good challenge for us. We had to learn how to achieve style without making the effects look too fake. We did this by paying attention to the way Seuss would draw effects.

"During previs effects exploration, we tried to adhere closely to the way Seuss illustrated effects like water, smoke, etc. We found that if you wandered too far from reality, it looked surreal. We had to find a middle ground where the effects were believable but stylized at the same time. We found that Seuss had a very specific way he would space things in his drawings and we tried to mimic that when placing our effects."

An animated feature that adheres even more closely to the look and feel of live action is the spacey comedy/love story WALL•E, which just opened from Disney•Pixar. After hundreds of lonely years of doing what he was built for, WALL•E (short for Waste Allocation Load Lifter Earth-Class) discovers a new purpose in life (besides collecting the waste that human left behind) when he meets a sleek search robot named EVE. She comes to realize that WALL•E has inadvertently stumbled upon the key to the planet's future and races back to space to report her findings to the humans who are hoping to return to the planet they deserted.