MPC Film’s Software Developer Christoph Genzwürker and Software Engineer Yanli Zhao talked about working on Tim Burton’s remake of Dumbo.
The team paid close attention to the distinctive skin of Dumbo and the elephants, and made sure their behaviour and look could not be distinguished from a real elephant.
In this talk, the team introduced a new workflow across Rigging, TechAnim and Lighting that was used to better accomplish this task and generate wrinkles on the skin automatically.
As one of the most iconic characters in movie history, when MPC Film was trusted with creating the elephants as CG characters, including Dumbo himself, the team wanted to make sure they looked as realistic as possible, both far from and close to camera.
The creation of high-quality wrinkled skin, e.g. for elephants, often consumes a substantial amount of time and memory for both simulation and rendering. Furthermore, detailed geometry has an impact on the infrastructure, including the network and servers responsible for data transfer.
To overcome these challenges, the team developed several tools in Rigging, TechAnim and Lighting to avoid unnecessary simulation and rendering of the wrinkles using a combination of low- and high-resolution geometry. With these tools, the artists were able to work smoothly with wrinkle-free geometry and to visualise the wrinkles quickly when required.
The Modeling department at MPC Film began by working traditionally, providing downstream departments with a typical-resolution 3D mesh of the elephant skin. New to this production, however, they also provided a higher-resolution version of the mesh, created by subdividing the original mesh twice (effectively producing 16x as many faces).
Due to the complexity of the high-resolution geometry, we had to adjust our pipeline to ensure that the TechAnim and Lighting departments could work smoothly and to guarantee that the many gigabytes of caches would not be synced between the MPC Film sites needlessly. To achieve this, the team made the decision to apply the simulation of wrinkles on the high-resolution geometry just before Lighting renders the shot.
The MPC Film rendering pipeline has a legacy of being based on Katana and RenderMan. Our typical approach for rendering characters would have seen artists loading the high-resolution geometry and caches directly in Katana, but that was simply impractical for the complexity generated on this project. So, to render the wrinkled geometry, the team processed the lower-resolution geometry cache using a custom Katana Op as can be seen in the diagram here:
To learn more, read the full article here.