There’s more to CG animation than a heartwarming or exciting story! We’ve already outlined the VFX pipeline and now we’re shifting gears to the CG animation itself.
There are 7 steps in computer animation and each of these processes is integral to creating high-quality animation. You simply cannot skip a single step. That’s the reason why creating an animated series or movie typically involves different artists from different departments working in sync to speed up the workflow. In this guide, we’re outlining all the essential processes of CG animation as well as the tasks that you can expect from each step:
The first step in CG animation is modeling, which is the construction of the virtual elements in a story: characters, objects, and sets. The task involves the construction of computer-generated elements using a computer program or a special effects application such as Autodesk Maya and Pixologic Z-Brush.
Small studios may ask the artists to create the model concepts themselves or provide the concept art direction. Depending on the project, the 3D modeler would create the characters and/or objects from scratch or use scanned data.
Complex models comprised of thousands of polygons do not take a lot of time to create but models that look as realistic as possible will take more time to construct using the smallest number of surface elements.
It’s not always the goal but most studios want the animation to be as life-like as possible and to make these animated objects look real, they have to be decorated and textured then rendered (more on this later) to form an image. For hyper-realistic results, 3D modelers would use hundreds of reference photos and 3D scans.
Character modelers must be well versed in two disciplines: hard surface and organic modeling. Hard surface modeling refers to the buildings, weapons, vehicles, ships, etc., while organic includes characters, animals, plants, and other natural objects.
Apart from getting the appearance of the character or object right, the 3D modeler has to perfect the details of the model to make the character as realistic as possible. A good example would be the CGI model for Grand Moff Tarkin, a Star Wars character portrayed by the late English actor, Peter Cushing in 1977. All the minute details of the actor’s facial expressions, mannerisms, and behaviors were incorporated in the computer-generated character so viewers cannot tell the difference between the original Tarkin and CG Tarkin.
After the modeling phase, the object will be passed to a surfacing artist who then adds texture and color to the 3D character accessories, or environments to enhance the visual appeal of the design based on the vision of the art director, production designer and/or film director.
To add textures and colors, the surfacing artist has to use specialized software applications such as Maya, Renderman, ZBrush, Photoshop, Mudbox, or Body Paint.
Apart from mastering all the essential computer application software for texturing and coloring, a surface artist should have a great understanding of lighting and shading so the project could be completed smoothly and quickly. Knowing different disciplines is always a plus in the animation industry, after all!
Rigging sets up the 3D character’s skeleton for movement. This process involves adding bones into a mesh, connecting the joints for more fluid movements. When creating a rig, the structure of the skeleton should be identical to that of a human or an animal’s skeletal structure. The same thing applies to vehicles, machines, and other moving parts. Because every rig is different, the corresponding sets of controls will vary.
Once the character has been rigged, the skin is added to the skeleton to complete the character design. This process essentially links all the vertices of the mesh to the joints of the 3D model.
At this stage, the models are brought to life by adding body movements. Cartoon is the traditional form of animation but in computer animation, the images are rendered with realism to make the characters, environments, and objects look as close to the real thing as possible.
Animating will require a lot of research and mastery over computer animation tools. The animator will also use a variety of techniques that include:
- Inverse Kinematics
- Physical Simulation
Depending on the complexity of the scenes, rendering could take a few days to several weeks. As for the quality of the CG animation itself, this will depend on the skills of the animator in interpreting the story.
Once the models and sets have been decorated and animated, lighting is applied. Back in the day, the simplest method of applying light involves using the primary colors that were assigned to the object or polygon. The effect is not as life-like but the process itself is fairly quickly, which allowed studios to produce shorts and movies faster.
These days, virtual light sources are used to enhance the lighting and adjust the intensity of the darkness and light accordingly.
A lighting artist would set a number of light sources in a space. He’ll choose the kind of light source to use based on the direction of the light (if the light is coming from one direction or scattered all around). The color or movement of the light will vary too. The light could be moving, flickering, flashing or it might not move at all.
Applying the lighting is one of the most complex and painstaking steps in CG animation because the virtual light must mimic how light behaves naturally in real life. You can’t just let a computer software do all the work, realistic lighting cannot be achieved by simply setting a few virtual light sources. It’s also worth noting that light does not exist in 3D so lighting has to be painstakingly applied in a number of settings and to the materials as well to achieve realistic results.
3D Camera Control
Camera is set to observe the optical characteristics of the animation. The camera could be set, angled, and moved anywhere in space using a software, mimicking focal length, depth of field, etc., to capture the scene. The 3D camera could also work the same way as a traditional movie camera, but without any weight or size restrictions.
Rendering is one of the most time-intensive stages in 3D animation because it brings all the elements of the frames together into one image. That includes the properties, surfaces, geometry, and lighting. Key details of the scene, such as the camera placements, lighting effects, and special effects, will affect the overall look and mood of the final scene.
Although rendering is the last step in the CG animation pipeline, it’s not the last phase of the production.
Depending on the complexity of the scenes and the resolution and quality of the image, it will take several hours to a few weeks to complete the rendering. The kind of rendering software used as well as the speed of the computer could also speed up or slow down the rendering process. Generally, a computer could render frames for a few seconds to several minutes. However, newer rendering software applications could render in real time.
This is the stage in the production when the rendered image could be edited and refined. This is the stage where live footage is blended with computer-generated footage. Special effects are also applied during this phase.
Once the frames are done rendering, the images could be played back on the screen before being transferred into a video or film. We’ve already discussed compositing extensively in this post, it’s worth a read!