I found another playblast of a Hellboy 2 shot I worked on so thought it would be fun to show it here and also explain how it was done.
It's from the film's 'Tooth fairy' sequence. The first half of the movie is the playblast, the second half is an early comp with basic textures and lighting, a first pass at the background 'swarm' fairies and a few of the other effects.
There were several narrative points that had to be addressed in this shot. In the first part the director Guillermo del Toro wanted the rolling statue covered in squashed Tooth Fairies, this had to then reveal a mass of dead and dying Tooth Fairies, twitching and writhing around.
I approached this by first creating a library of cycles that I could reuse quickly and easily to create a moving carpet of the creatures.
Above I've named the cycles and shown how they were applied ... as best as I can remember.
Face Up 1, Face Up 2 and Face Down are cycles I kept predominantly still but with some random spasms and twitches.
Twitcher - Flails around, letting out an agonising scream then finally relaxes and coils into his death pose.
Kicker - is based on an insect video I found on youtube. The idea is that the dead insect's nerves keep his legs kicking, this drives his body round in a circle.
Crawler - with his legs and one arm badly injured, this fairy pulls himself along by his one good arm.
The rigs also had a clever function - a series of blendshapes that could be dialled in to give the effect that a leg or arm was missing. There were also shapes that got rid of everything but the chest, head, or hips and legs. This meant I could quickly and easily make the cycle look very different by removing half the fairy, or could superficially make a cycle look distinct just by removing a few legs or an arm.
I populated this section of the shot with these characters, then tried to create 'hero' tooth fairies to give the viewer interesting things for their eye to settle on ... and also to amuse myself. There was a platform in the top left of frame so I placed a hero 'kicker' on there - he drops off the statue then feebly kicks himself in a circle. In the centre of the picture, '2' drops off the statue into frame to draw your eye into the picture. '3' - a badly injured 'crawler' drags his torso forward leaving the rest of his body behind.
The next level of Fairies had to interact with the characters, these were some of the most fun to do. They are lead by the actions of the actors who are miming being attacked by the creatures. It was then my job to find a series of movements that would fit the actions performed. For this to work convincingly, the characters movements have to be rotoscoped onto CG doubles. My memory's a bit hazy here but I think I did both Hellboy and Abe in this shot, (apologies if it was someone else). Double Negative had a neat little tool that made it easy to constrain the Tooth Fairies to the geometry of the CG doubles and it could be easily animated on and off as they landed and then took off or got hit.
There are four of these 'attacking' Tooth Fairies in the shot, two on Abe when we first see him, one who lands on Hellboy, and one much later, and you'll have to look very closely for this, on Abe's leg when he is on the stairs - Abe sweeps him off, he hits the banister and bounces back onto the stairs and is then stood on.
I'm always impressed by actors who can convincingly mime such actions with nothing to guide them, it also makes the animator's job a lot easier. The actor who plays Abe, Doug Jones, is awesome at this, I hope to write a post on just this soon.
The next level of Tooth Fairies are the ones that are to be shot by the various characters, you'll notice in the playblast in the top video that the gun blasts are absent. It was up to me to work out when the best and most appropriate time for the gun to go off. Again much of this is driven by the performance of the actors.
To create exploding fairies I was able to use the limb removing blendshapes I mentioned before. When a fairy is shot his visibility is switched off, at the same time several other fairies appear with their various parts hidden, they are then scattered to create the impression that the fairy has exploded. The effects department then added in some liquidy gloop to give the fairies a nice splat too.
I also used this technique for the fairy that Hellboy swipes, I thought that since Hellboy is supposed to be incredibly strong it would be good to have this one disintegrate with the impact.
Each rig in the scene slowed it down so I tried to be as efficient as possible with my Tooth Fairies, you'll notice many of the attacking, or being shot in the background swoop past camera to get extra value out of them.
Amusingly, in the first playblast a member of the on set crew also makes an appearance, he was painted out in in final plate.
Here is the finished shot. As you can see many extra effects have been added - the swarm stuff is awesome as is the fire and tooth fairy blood and goo, on the ground around the dead fairies.