For Cherry’s leg, TMD had hoped to develop an automatic tracking solution, but a keying solution was used instead. 

A director with a strong emphasis on visuals, Rodriguez relied a lot on animatics to develop concepts for the movie. "Most of our animatics were a guideline or visual blueprint to aid in communication on set," Olivia adds. "We try to take them to a finished look when we have the time to in order to help establish the mood, choreography and pacing upfront. There was one instance, in the Machete motorcycle jump animatic, where I recreated the practical rig that would be used on set to fly the motorcycle through the air. I set the CG bike up on this animated rig and flew the virtual camera towards it to make it look like the bike was flying through the air. Once Robert approved this, I was able to provide different views and schematics of the virtual scene to other departments to use for the actual shoot."

A Leg One Could Kill For
Planet Terror features a lot of colorful characters, but in terms of uniqueness, no one comes close to Cherry (Rose McGowan), a tough lady who wears a fully loaded machine gun as a leg! Early in preproduction, Toader and Olivia built an in-house gunleg version for animatics and to help in the design. Once the final design was approved and built by the props department, Eyetronics scanned the prop and built a CG model. "Early on, we hoped to develop an automatic tracking solution, but due to discomfort and safety requirements, the L.E.D. cast the actress wore was thrown away, and we focused on a keying solution," Brunet says. "The green boot which lit up in a grid pattern became a diffuse gray stocking with limited leg movement, but did allow a slight knee bend if needed by the actress. Ultimately, we hand-tracked the bandage and gun in XSI for every leg shot. The actress wore an ace bandage that we blended the CG element into. It also gave us a consistent measurement to match."

Adds Dela Cruz, "There wasn't always a clean plate. And even for those shots where a clean plate existed, the camera wasn't motion controlled, so matching the two shots was difficult. Most shots began by removing much of Rose and the background. Clean plates were manufactured in Flame or Photoshop, and tracked into the scene. Then, specific parts from the original plate would be rotoscoped back in. Each background plate posed unique challenges. Shots that one thought would take five minutes took three days. More difficult looking shots sometimes took only hours."

The Sickos’ look was realized through special make-up effects created by KNB EFX Group with several enhancements by The Orphanage.

In several scenes, Cherry wears a mere table leg instead of her signature gun. Although looking simpler than the gun leg, at least on paper, the effect turned out to be much harder to sell as being real. Animation was made difficult by the fact that the prop connected to the actress above the knee. Any movement by the actress shifting her center of gravity or bending her knee caused the CG object tracking to look wrong. In many shots, a rigid table leg would travel below the deck or floor… To overcome this, the final table leg rig gave the team a lot of freedom to lock the tip to the floor, but also allowed a natural hinge or joint under the bandage.

Joining Rose and pals in the zombie bashing is a wild biker (Danny Trejo) who rides a Gatling gun-equipped motorcycle. In a key vfx shot, the character jumps on screen while a massive explosion occurs behind him. "The plate was shot with a rig raising the cycle and actor about six meters off the ground," Brunet notes. "The rig was remotely controlled to rock the cycle back and forward while spinning the wheels. Trejo was placed on top of this contraption and fired blanks out of the gun while a massive pyro ball was detonated from behind at a safe distance. We took that footage, replaced the sky, removed the rig and added CG bullet shell casings on takes where he did not fire the gun." The effect of moving forward in space was achieved by animating in XSI a 3D camera past digital models of power lines, particle smoke and a textured sky dome.