CGSociety

Sketches

Once my mental image of the concept became clearer, I decided to create a large structure made up of small parts collectively forming a vaguely humanoid pose. The individual elements of the composition would be something similar to corals. Given this inspiration I quickly sketched the pose using my daughter's set of color pens.

Modeling

This project turned out to be quite simplistic in terms of the modeling required. Due to the limitations of my hardware, I learnt the importance of scene optimization the hard way. The bulk of the scene was based on the construction of a few master objects that were instantiated and arranged to establish the overall structure - a process somewhat like modern house construction where you have multiple copies of a few standard modules and snap them together to form the complete structure.

I used the standard Cinema 4D stickman primitive to pose the structure by pushing it around and experimenting until it matched my sketches. Once posed, I undertook the rather tedious task of replacing each individual part and limb of the stickman with linear splines which I would later use to guide the coral object instances and to generate wires crisscrossing the scene after the fashion of a huge spider web.

With the splines in place, I made several groups of assorted coral segment instances, each matching a certain spline (e.g. upper left arm, lower left leg, etc.). I placed the individual objects using an align-to-spline expression. At this point I noticed it didn't look quite right - their placement was somehow too mechanical and procedural. To fix this I manually moved and rotated each segment individually in a semi-random fashion until it had the 'alien coral' feel I wanted.

The head of the structure required a different approach. I wanted to translate the organic, twisty nature of the corals into some sort of building. I manufactured the final look by constructing a few different tall buildings and grouping them together using a combination of taper, twist and bend deformers to achieve the right outline. To give the structure a touch of that gravity-defying alien quality, I intentionally made it rather large and tilted at a potentially dangerous angle.

Clearly this project required a still image for the final piece, but given the the challenge theme I wanted there to be a sense of dynamism and motion. Since the theme referred to the creation of something, I considered what kind of phenomenon could serve as a creational, yet dynamic and chaotic force. The answer was an explosion. I guess my mind went to the idea of the Big Bang, which was indeed a creational force in spite of its violent nature. Since that event was supposedly the birth of everything we know, I decided to give my main structure a slightly pregnant belly - then blow it to pieces. Thus, the forces of creation and dynamism were neatly packaged in a single burst of chaos and debris. The modeling for the explosion was easily accomplished with a sphere, magnet tool editing, some extrusions and an Explosion FX deformer.

I decided to add something smooth and wobbly swirling behind the neck of the structure for the final touch. The basic mesh for this was modeled using matrix extrusions and then carefully shaped with FFD, bend, wind and twist deformers.

Textures

Due to the alien nature of this project, I needed shaders that didn't resemble anything in particular, but still looked believable in terms of complexity and richness. I started testing various procedural setups using the same approach as I would if the goal was to make something realistic, but trying to avoid anything that looked real. The SLA procedurals in Cinema4D have an incredible range of noise algorithms, and I chose a particular one called Buya. This was mapped and scaled until I had a good combination to use as a base shader. I made a few duplicates of that base material and applied some minor tweaks at random to the copies to get some overall diversity.

Other textures were created by grouping several buildings rendered separately and alpha-mapping these onto single-poly planes. These were used to make up the organic flavor of the landscape/cityscape towards the very bottom of the background. I needed hundreds of buildings to get the desired result, and doing it with real geometry was out of the question. This 'billboard' approach was the only way to achieve it in the given timeframe.

Early concept

Main structure segments

Buildings 'billboard' background elements

Explosion test render and background 'billboards'

Lighting

There are three different kinds of lighting happening in Submerged Ballet: the visible spotlights scattered over the main structure, the caustic streaks dominating the background, and thirdly the ordinary stage lights (key and fill lights).

The small visible spots were built using pairs of coaxially aligned parallel spotlights, with varying ranges and radii. Six such pairs were grouped together in a radial arrangement, and these in turn were instanced across the model together with some geometry using the guide splines.

The caustic streaks were produced by applying a light gel with a caustic pattern bitmap to a volumetric spotlight. Unfortunately this arrangement required extremely high quality settings to avoid artifacts when rendered at print resolution, so despite the background pass containing nothing more than this caustic spotlight and a gradient backdrop, it took approximately seven hours to render.

The basic stage lighting was very simple - a key spotlight held high above and to the left of the main structure with fill light almost directly below this. Both lights were set to generate soft shadows. Due to the placement of the key light, it provided quite a lot of rimlight quality as well, so no dedicated light source was required for that.

Rendering and post-processing

One of the most important features of the final render is the strong sense of depth provided by the murky alien mist which endows the piece with a feeling of being underwater. Ordinary distance fog did not produce the desired result and volumetric fog shaders were far too slow in terms of rendering and therefore unlikely to end up looking the way I wanted (please note that my entire project was made on a 466 MHz Celeron with 192 MB RAM). The solution was to map my background gradient onto four infinite planes evenly distributed along the depth axis, and lower the opacity to make each plane semi-transparent. This way I produced five different zones of haze which became thicker with each step away from the camera. By placing the building 'billboards' and the pre-rendered background structures in different haze zones, I was able to control the overall feeling of depth with complete accuracy. Importantly, I could experiment without having to wait for test-renders since the viewport feedback was sufficient.

I used only two main layers in the final rendering - the background with haze planes, buildings and the caustic light pattern, and the foreground with the main structure using copies of the background haze planes. The background pass also included two main structures further away from the camera with different rotations, pre-rendered with alpha channels for easy render-time compositing. The final layers were rendered using the Cinema 4D multi-pass feature which, among other things, allowed me to easily adjust the amount of key and fill light separately in Photoshop after the rendering was completed.

Further 2D post-processing included some brushing in color dodge blending mode, color rebalancing and levels and contrast adjustments. I also added a touch of diagonal rain-like streaks to emphasize the overall chaos.

About Kaufeldt

I'm 36 years old and live in southern Sweden. Since the age of 13 I've spent most of my time in front of various computer screens, but only began playing with 3D CG in mid-2000. I started out using Blender, but was lucky enough to be able to switch to Cinema 4D in August 2003. I have been serious about 3D for exactly one year - a time period corresponding exactly to the current extent of my CGTalk membership!

I've been working periodically as a teacher in various computer-related domains in the past few years, mainly in programming and web design, but am currently seeking an appropriate job in the CG field to take advantage of my skills.

Occasionally I leave my 3D for and indulge in my other interests: drawing, writing short stories and making music.

Related Links
James Kaufeldt’s challenger gallery
Submerged Ballet by James Kaufeldt
The Alienware Challenge 2004

Background layer rendering

Words and images by James Kaufeldt