FX & PIPELINE ARTIST
ANIM MANAGEMENT TOOLS
LHABITANT ADRIEN 13 March 2024
INTRODUCTION
For the creation of the short film 'El Dodorado', we decided to use Maya for modeling and animation. However, we chose to use Houdini/Solaris and the USD (Universal Scene Description) format for Lookdev, set dressing, grooming, FX, and finally, batch setups. I had to organize the transition of animations between Maya and Solaris using multiple scripts in both software packages.
I'm going to detail the steps and process I took to establish the pipeline between the animation team and the rendering team.
MAYA SCRIPT FOR ANIM TEAM
DODO RIG IMPORTER
The animators being comfortable and experienced with Maya, I had to develop scripts to import rigs into the animators' Maya scenes to make the import of multiple Dodos into the scenes easy and quick. This also allowed for integrating namespaces to avoid conflicts between the different Dodos, especially when practical needs arose. We had to split the animation scenes for a single shot when the number of rigs became too large in the scenes, which also allowed us to use Studio Library to store poses and animations.
Therefore, we have a Maya shelf that stores all the scripts useful for production.
The script lists the available Dodo rigs and imports them as references into the Maya scene according to the desired quantity.
DODO ABC EXPORTER
Then, we had to create a script for exporting animations. We decided to stick with the Alembic format because we encountered issues exporting USD from Maya to the server. Another problem was that visibility is not available in the Geo context in Houdini in USD, unlike Alembic, which was much more convenient for many automation tasks.
The script simply allows selecting the Dodos to export by specifying the frame range. The script will locate the geometry group to export it. We export visibility attributes, which we use to employ various types of beaks or feathers on the Dodos.
The script automatically exports the Dodos with the correct nomenclature in the corresponding shot folder. We also indicate in the name of the Dodo in Maya the plane on which it is located (FG, MG , BG) . This determines the quality of the fur assigned to it based on its distance from the camera.
The script will also create a JSON file that indicates the frame range of the shot, which we will later use for various Hython scripts for different pipeline automations.
Modeling and texturing by Talhia BRAUM
HOUDINI SCRIPT FOR ANIM ON USD
As mentioned previously in the introduction, we opted for Houdini/Solaris for the film's rendering aspect, primarily to leverage the USD format for enhancing collaborative work. Additionally, we aimed to tackle the technical challenge of handling a significant amount of animation, whether through Alembics or with the crowd system, alongside a real-scale island.
To address these needs, I developed a small interface that integrates multiple Hython scripts (Houdini's Python language). These scripts enable us to import Alembics from the shot folder and automatically save them as USD files with the appropriate scale (0.01). Subsequently, we generate FG (Foreground), MG (Midground), and BG (Background) USDs based on the USD nomenclature within Solaris.
EXEMPLE
We will utilize these three USD files to determine fur quality within our automation, along with many other details that I will elaborate on later.
In the next article, we will see how I use each USD file in fur automations and how the crowd system works to create the entire visual workflow of the dodos.