The engine is very flexible because all it wants to know is where you want it to burn, so we could do all types of looks with it. In one day we could look at two or three takes of the fire, so we got more turnaround with it. Once you have your low-particle-count simulation, then you feed that into the Verte, which is in the GPU. "Chris wrote the whole engine on the Nvidia video card, so it's hardware-accelerated," Alexander says. By piling up a bunch of slices together, you still get dimensionality to it but you're giving your time and energy to the screen space, where you need it, like the edges of the flame where you want to see those little licks. "If you look at a fire, it's actually pretty difficult to tell how deep it is. Since the fire itself is moving, the particles move from slice to slice in 3D. "You can get really nice detail around the edges of the fire and you can get speed out of it because you're not worrying about depth." The fire effect's 3D volume is "sliced" like a loaf of bread, focusing on the X and Y dimensions, but not the Z axis. Horvath's engine calculated how the particles would burn "but he does it in two-dimensional slices so he can do very high-resolution simulations very quickly," Alexander says. "We still did a particle sim, but it's a very low particle-count, like fuel flying around in the air, just to tell us where it's going to burn." The team put this low number of particles into a tornado configuration, made it look good, and then ran it through Horvath's secondary engine that actually simulates the fire. Alexander credits it and the resulting fire effects as ILM's biggest achievement in the film. He ended up using a new approach developed by ILM's Chris Horvath. However, Alexander says, "You have to have such a high density of particles to create the detail that you need in fire that it very quickly becomes unwieldy and slow." ILM's first approach was the standard "brute force" method: Simulate particles - "a lot of a lot of them" - into a 3D volume to try to emulate the look of fire. Fire's pretty difficult and we didn't have a solid solution for it." Still, the decision was to forsake ILM's successful history in filming practical pyro effects and to go with all-CG flames. Despite their brevity, says Tim Alexander, ILM's VFX supervisor on the film, the fire shots "chewed up a great deal of our time and energy. The culminating sequence is about seven minutes long and the fiery climax is only about eight shots. For this sequence's effects Yates called ILM.
Dumbledore even hurls submarine fireballs at the enemy as they retreat underwater. In the novel he engulfs the aggressors in vast sweeping arcs of flame that he controls, creating a vortex of fire.
They land on an island in a crystalline cavern where thousands of undead humanoids - Voldemort's victims-now-minions - suddenly emerge from the waters, ensnare Harry and drag him down into the murky depths.ĭumbledore reacts with a new trick. It's fairly easy to describe HP6's climax on paper - Rowling did it - but how, exactly, would you do this on film? Harry and wizard/mentor Dumbledore enter a foreboding watery cave on the trail of ultra-bad guy Voldemort.
There's a seventh novel yet to be filmed, so we presume that the budding wizard will need to survive the implacable mortal threat at the climax of HP6.
film, directed by David Yates, is the sixth and penultimate installment in the series based on J.K. SAN FRANCISCO - The climactic sequence in Harry Potter and the Half-Blood Prince is one of the most (if not the most) complex compositions of live actors, greenscreen, CG characters, environment, simulated natural phenomena and simulated fantasy phenomena I have encountered in 21 years of writing for Post.