Motion Picture | Fire and Ice | Ice dragon

Fire & Ice (2008) TV

Director: Pitof

Plot:

Ruled by King Augustin, Carpia is a peaceful kingdom in a world inhabited by dragons and knights. The land’s serenity is unexpectedly shattered by a Fire Dragon that spreads almighty fear and death amongst the kingdom’s innocent people…

http://www.imdb.com/title/tt1135493/

Final result:

Breakdown:

How to:

fire dragon post quote:

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This project was quite a difficult mission for us because of the more than 450 full cgi vfx shots. The timeline was a little under 7 months of production, starting from the day the edit got approved.  3 months before, we started with the previz and the setup of the whole pipeline to fit the deadline.

This is the reason behind the automation of this project. All the shading, td setup, simulation and rendering are script driven.

This is an example of the the flow in our project:

 

 

 

 

 

  • we take the master previz scene and generate (camera name based) the files for animation.
  • the files from animation get baked and cleaned, removing helpers and dummy stuff. Then we output 3 other files: shading, particle effects and environment.
  • the shading files use script based action for automation of the basic texture assignment, shading settings and light placement. After this, we teak around for desired effect and then we out put again, by script, files for beauty renders, layers and utility maps. All these are going straight to render farm.
  • the particle effects files split into 2 different files: low quality settings simulation and high quality settings simulation. The LOW Q settings simulation files output data to be used for simulation driven particles. The HIGH Q settings simulation files output data straight to render farm as fire, smoke and volume zdepth layers.
  • the environment files split into 2 separate direction: one is full cgi geometry and the other is mate paint projection. Both output all the beauty plus utility layers by script.

 

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previz

The previz animation was done during a 2 months and a half timeline. In that period of time the animators team build entire movie sequences that were followed by camera placement under director’s supervision. All the cameras were then rendered as previz to quick time files used in the edit.

After the final edit got locked we took the master files and break it apart for every shot.

The following shot is a close up of the fire dragon while the first village  attack.

model

The model concept came as a special request of the director. It is supposed to look the same as the Fire Dragon, the main difference being that this creature draws its powers from a different elemental: water/ice. This is the concept drawing of the creature that is to be the Ice Dragon

Ice Dragon concept

This is the clay model of the Ice Dragon.

Ice Dragon model

animation

Compositing and layers

Environment

The environment for this shot is quite a challenge because of the large distance of flight trajectory. We are close to the top of a high mountain that was striped mined for salt. Simply put it is a hollow mountain, made out of ice, with the ceiling collapsed and exposed to the sky for many years. We get a volcano like volume with huge stalagmites pointing out to the sky. Our dragon it is not a small creature. It is about 30 meters wide, but in this environment it looks small and fragile.

The idea being this set is that salt melts water and following this thought, movie hero decides to lure the dragon into this salt mine and collapse the remaining walls and stalagmites on top of it.

This is the comp of the environment

Salt mine composition

We split the render in two parts:

  • the cave itself
  • the stalagmites

The cave is simply built, like a cauldron. Our dragon comes flying from outside of the mountain, over the top and then plunges inside the salt mine. This is the reason why the cauldron and the outside wall are 2 separate layers/renders combined trough a gradient ramp later on.

The cauldron

Salt mine cauldron

The stalagmites are rendered using a vertical ramp for translucency because they are supposed to be made out of salt. On the layer of the stalagmites we still have the low poly geometry of the cauldron for the light bounce to be correct.

These are mated by a mask and added on top of the cauldron

stalagmites

Salt mine stalagmites

mask

Salt mine stalagmites mask

A z depth ramp + a vertical ramp were rendered in order to darken the depth of the salt mine and also add an atmospheric haze to the scene.

ramp

Salt mine ramp

The Ice Dragon

The approach to build the Ice Dragon is straight forward. We get a beauty pass that we alter by color correction nodes driven by horizontal ramps and ambient occlusion pass for the cracks and creases.

The two color corrected results are then merged with animation keys on the blend factor. The reason behind this is that the dragon is light blue and the sky is clear and crisp (producer request). This way is very hard to get any kind of contrast between the two, so we animate the blend between the light blue version dragon on top of the dark blue version dragon, considering the background of a given shot. The aproach seems overkill, but if you consider this a scripted precomp, you can easily tweak for every shot and then start from there.

Ice Dragon comp

Ice Dragon comp

Light Blue version dragon

Ice Dragon light blue

Dark Blue version dragon

Ice Dragon dark blue

A major part of the Ice Dragon is the icy mist it leaves behind.

To get the dragon inside that cloud of particles we used a Z depth layer to mate the particles on top of the dragon. Beside the Z depth, for the Ice Dragon there are rendered also 2 horizontal ramp for altering the tips of the wings, wing and body separately. Also, a mask for the head, eyes and teeth is used to separate these elements. There are not visible in this shot, but it worth mentioning.

Ice Dragon Z

Ice Dragon Z depth

The Volumetrics

A major contribution to the Ice Dragon is the icy mist around it. To get this to work as a volumetric cloud with nice fluid like dynamic we took the same aproach as for the Fire Dragon.

Particles composition

Ice Dragon particles composition

We took the animated baked mesh and calculated the volume needed to enclose it’s whole trajectory. With in this volume we build by script a voxel grid for a Fume Fx simulation. The settings are not to be high quality because the render result is going to come from a different setup.

This is the Fire render of the Fume Fx simulation. We use this as a tiny detail trough the composition. Also the color gradient of the fire gets modified to fit this sliced energy like object.

Ice Dragon Fire

The simulation result is used to drive 2 particle flow systems. One follows the same dynamics of the voxel grid and the other has some additional noise speed that is combined 50% with the voxel grid motion.

These systems are then fed into Krakatoa partitioning system. The partitions reside on network storage, so it is very simple to submit by script every partition to be cached by a different blade on the render farm.

When the caching process ends, we take these partitions and we load them into 2 different blank files. We create by script a 3 color light setup for render. The 3 lights have complete different color. One is completely red, the others are completely green and blue. This way I can isolate by channels value different parts of the particle cloud. This way I can animate into compositing different intensities mask by channel values and create a more dynamic cloud then rendered already.

One system is rendered as volumetric density

Ice Dragon particle volume cloud

The other system is renderd as additive density cloud to get the plasma like effect inside the icy mist

Ice Dragon particle additive cloud

All the particles are composited against the salt mine background because we need the environment colors to be present in the misty semi-transparent layers. Because of the heavy color corection within the particles layers we prefer to blend the background into this. We premultiply after this to continue the comp.

Particle layer comp before premultiply

Ice Dragon particle comp before premultiply

Next step we add the clouds and use the Z channel of the dragon and particles to get them inside the haze. The clouds are Afterburn voxel spheres generated by particles stuck on vertices of a base/guide mesh for clouds. These are suposed  to be a more meaty fog then clouds, that is the reason of the missing details and the swirls.

Clouds

Ice Dragon clouds layer

This is the final comp as a whole.

Ice Dragon final comp

and the final shot, before color correction