FLIP Fluids 2.0
The following text is an edited transcript from the FLIP Fluids Addon Development Update 2022-2023 video (timestamp 11:15).
As was mentioned in the last development video, we had been working on a new project to expand the simulation and visual effects capabilities of Blender. We have now been developing this project for a bit over two years and we want to share more details with you about this project.
Beginning in May 2021 we had started a complete re-write and re-design of both the liquid simulation engine and FLIP Fluids addon. This project will be released as a free update to the FLIP Fluids addon and we are currently naming this project FLIP Fluids 2.0.
This is an ongoing project and there are still a lot of unknowns to us for what some aspects of this project will become. We will only be updating you with details on our solid plans for this project. We won't be speaking on features that are currently in an experimental stage or features that may not end up working out in the end in order to avoid disappointment if we are unable to reach those goals.
You may have some questions about this project, and we have seen a few from you since our last development video. We are now ready to share with you some more quick details about FLIP Fluids 2.0.
Development of FLIP Fluids 2.0 has been slow but steady. Over the last year, we have been portioning a larger amount of development time towards the FLIP Fluids 2.0 project versus the current FLIP Fluids addon in order to accelerate development. This has meant that the current FLIP Fluids addon has received less development attention in large new features, but we are still continuing to maintain, update, fix bugs, and add smaller improvements in each version release.
There is still a long way to go in development before the FLIP Fluids 2.0 project will be ready for launch and we do not have a set timeline at this moment. Keep in mind that the we had also spent a few years on development and testing of the current FLIP Fluids addon before the product was able to meet our high standard of quality. We will let you know when we are more certain of a date for a beta release or a full launch of the FLIP Fluids 2.0 project.
There are a few reasons why the simulator and addon are undergoing a re-write instead of modifying the current FLIP Fluids addon:
- When we first created the FLIP Fluids addon, we had never expected the addon to grow as large or as popular as it is today in the Blender community. We have learned a lot about simulation and Blender addon development since the initial release over the last five years. Some design decisions made early on and some developments of Blender that we did not expect have resulted in deep design issues within the addon that have impacted our development in a negative way. These design issues have limited our ability to progress on some of the most requested features and improvements, especially in improving performance. Our long-term goals for the FLIP Fluids addon have outgrown the current engine and a re-write is the best path for us towards meeting these goals.
- One of the largest design changes for FLIP Fluids 2.0 will be that the simulation engine will run outside of Blender rather than directly inside of Blender's Python environment. This gives us more control over how we can ensure stability while the simulation is running, allows us to work around limitations of running the simulator directly within Blender, and allows us to further improve performance. Moving the engine outside of Blender is just a technical detail - the integration with the addon will still feel the same to the artist. The only difference that you will see is that running a simulation will start a separate application that runs in the background.
FLIP Fluids 2.0 will continue to be an open source project. Moving the simulation engine outside of Blender technically allows for closing the source code of the engine, but we have zero interest in doing this. We are committed to open source development and will continue to distribute the source code under open source licenses such as the GPL and MIT licenses.
After FLIP Fluids 2.0 is launched, we do plan to extend the engine to handle other types of simulations outside of liquid simulation. A large part of the design of the new simulation engine is to allow for us to more easily extend the codebase to handle other types of simulations in future development. We are not certain which types of simulations we will start on first, but any simulations outside of liquids will be released as a separate product in order to fund development.
We are experimenting with speeding up some computations using the GPU, but GPU acceleration will not be a major feature of the FLIP Fluids 2.0 engine. A real-time simulator that runs fully on the GPU is not something that is realistic for us to develop at the moment. For the initial release, GPU acceleration features may be limited to NVIDIA hardware.
Our primary goals for the FLIP Fluids 2.0 engine are to greatly improve performance and to remove design limitations that have prevented us from developing some of the most requested features and improvements. Here are some quick notes on some of the more important features that we are designing into the engine:
- Sparse and adaptive domain simulation to improve performance and reduce resource usage, allowing for much larger simulation effects.
- Ability to animate the domain position and dimensions to reduce the amount of simulated liquid in effects that require moving over large distances.
- Improvements on domain boundary conditions. For example, setting domain walls with inflow or outflow speeds, setting a water level to maintain, generating ocean waves, and more.
- Decoupled baking workflow to optionally separate the baking and re-baking of different simulation components: fluid particle simulation, mesh generation, whitewater generation, and other simulation processes.
- Updated whitewater simulator. Blender has massively improved the efficiency of particle rendering in both speed and resource usage. Being able to generate and render more particles allows us to make some nice improvements in realism for how whitewater can be generated.
- Support for multiple simulation domains within a Blend file.
- Possible particle system support. Depending on the development of simulation nodes or Blender's plans for a new particle system, we may be able to add support for particles systems as inputs into the simulator.
- These are just a few, and there will be many more changes, improvements, workflow features, and surprises for FLIP Fluids 2.0.
Thank you for taking time to listen about what we have been working on. The Blender community has been so friendly and supportive during the development of the FLIP Fluids addon project and it has been a real pleasure to develop this tool for the community. We are looking forward to the day we can launch the FLIP Fluids 2.0 project and are so excited to see all of the animations and effects that you will create. We are certain that the wait will be worth it.