Functional Optimization of Fluidic Devices with Differentiable Stokes Flow (Siggraph Asia 2020)

System requirement

• Ubuntu 18.04
• (Mini)conda 4.7.12 or higher

Installation

git clone --recursive https://github.com/mit-gfx/diff_stokes_flow.git
cd diff_stokes_flow
conda env create -f environment.yml
conda activate diff_stokes_flow
./install.sh

(Optional) Configuring Pardiso

Let <PARDISO_HOME> be the folder that you saved your Pardiso license file and the binary file. For example, if /home/pardiso/pardiso.lic and /home/pardiso/libpardiso600-GNU720-X86-64.so are your license and binary files, then <PARDISO_HOME>=/home/pardiso.

• Set PARDISO_LIC_PATH and OMP_NUM_THREADS:

export OMP_NUM_THREADS=4
export PARDISO_LIC_PATH=<PARDISO_HOME>
export PARDISOLICMESSAGE=1

• Pardiso requires lapack and blas:

sudo apt-get install liblapack-dev
sudo apt-get install libblas-dev

As of the date this README is written, the version we use is 3.7.1-4ubuntu1:

Reading package lists... Done
Building dependency tree
Reading state information... Done
libblas-dev is already the newest version (3.7.1-4ubuntu1).
liblapack-dev is already the newest version (3.7.1-4ubuntu1).
0 upgraded, 0 newly installed, 0 to remove and 132 not upgraded.

• Recompile the codebase with an optional pardiso argument:

./install.sh pardiso

Examples

Navigate to the python/example folder before you run any of the following scripts.

Results in the paper

Run python run_demo.py [demo_name] where [demo_name] can be any of the following;

• amplifier: run the Amplifier demo (Fig. 2) in the paper.
• flow_averager: run the Flow Averager demo (Fig. 4) in the paper.

• superposition_gate: run the Superposition Gate demo (Fig. 4) in the paper.

• funnel: run the Funnel demo (Fig. 4) in the paper.

• fluidic_twister: run the Fluidic Twister demo (Fig. 5) in the paper. Note that the original result was run with a resolution of 64 by 64 by 32, and we downsampled it in this codebase for a faster demonstration.

• fluidic_switch: run the Fluidic Switch demo (Fig. 1) in the paper. Note that the original result was run with a resolution of 64 by 64 by 32, and we downsampled it in this codebase for a faster demonstration. The two figures below show the optimized solution in two modes:

Numerical tests

Run python [script_name].py where [script_name] can be any of the following:

• bezier_2d: show the level-set of a Bezier curve and check the implementation of gradients.
• cell_2d: check if all quantities in Cell2d are implemented correctly.
• scene_2d: check the gradients of loss defined in a 2-dimensional scene.
• shape_composition_2d and shape_composition_3d: check the gradients of composing multiple primitive level-sets. Finally, if you would like to run all these numerical experiments above, you can simply call run_all_tests:
• run_all_tests: this will sequentially run all the aforementioned numerical tests.

Run python refinement.py to generate the numerical results in Fig. 8 in the paper.

Rendering

Run python pbrt_renderer_demo.py to see how to use the Python wrapper of pbrt-v3.

Additionally, we have also provided a few Python scripts for generating figures in the presentation:

• python draw_pipeline.py: generate each subfigure in the whole pipeline.
• python draw_design.py: generate pictures for the design section.
• python draw_discretization.py: generate pictures for the discretization section.
• python draw_optimization.py: generate video and pictures for the optimization section.

How to cite

@article{du2020stokes,
    author = {Du, Tao and Wu, Kui and Spielberg, Andrew and Matusik, Wojciech and Zhu, Bo and Sifakis, Eftychios},
    title = {Functional Optimization of Fluidic Devices with Differentiable Stokes Flow},
    year = {2020},
    issue_date = {December 2020},
    publisher = {Association for Computing Machinery},
    address = {New York, NY, USA},
    volume = {39},
    number = {6},
    issn = {0730-0301},
    url = {https://doi.org/10.1145/3414685.3417795},
    doi = {10.1145/3414685.3417795},
    journal = {ACM Trans. Graph.},
    month = dec,
    articleno = {197},
    numpages = {15},
    keywords = {physically-based simulation, fluid simulation, computational design optimization}
}

Contact

If you have any questions about the paper or the codebase, please feel free to contact [email protected].