Asteroid Impact Volume Rendering

VTK volume rendering of an asteroid impacting the ocean. The dataset comes from LANL's Deep Water Asteroid Impact ensemble. See docs/MeaningOfDataAsteroid.pdf for details on the simulated scalars (v02, v03, tev, prs).

The full-quality video is at media/asteroidRendering.mp4.

Dataset

The simulation timesteps aren't included in the repo (too large). Grab them from LANL's Deep Water Impact Ensemble and drop the .vti files into Data/. Each scalar means:

• v02: water volume fraction
• v03: asteroid volume fraction
• tev: temperature
• prs: pressure

Setup

python -m venv venv
venv\Scripts\activate          # Windows
# source venv/bin/activate     # macOS/Linux
pip install -r requirements.txt

Scripts

There are two kinds of scripts here. The Asteroid*.py files are interactive PyQt5 viewers that let you tune the look of one scalar at a time on a single VTI file. FolderRendering.py is the batch renderer that loops over a whole folder of VTI timesteps and writes out PNG frames using the tuned settings hardcoded in its DataStructure dict.

Interactive viewers

Each one opens a PyQt5 window with sliders for the transfer function of a single scalar.

Script	Scalar(s)	Usage
AsteroidV02.py	water (v02)	python AsteroidV02.py path/to/timestep.vti
AsteroidTev.py	temperature (tev)	python AsteroidTev.py path/to/timestep.vti
AsteroidPrs.py	pressure (prs)	python AsteroidPrs.py path/to/timestep.vti
AsteroidIso.py	isosurface of v02 + prs	python AsteroidIso.py prs.vti v02.vti data.vti
AsteroidsCombined.py	all three combined	python AsteroidsCombined.py prs.vti tev.vti v02.vti data.vti head.vti

Common flags: -r W H (resolution), -o NAME (frame screenshot prefix), -v (verbose).

Batch frame renderer

FolderRendering.py is what produced the video. It walks a directory of VTI timesteps, renders each one with the asteroid, water, and temperature volumes composited together, and writes sequentially numbered PNGs (0.png, 1.png, ...) to an output folder.

python FolderRendering.py "path/to/folder/of/vti/timesteps" --output frames/

Once that finishes, encode the frames with ffmpeg:

ffmpeg -framerate 30 -i %d.png -c:v libx264 -pix_fmt yuv420p output.mp4

Repo layout

.
├── FolderRendering.py            # batch renderer (produces video frames)
├── AsteroidV02.py                # interactive: water
├── AsteroidTev.py                # interactive: temperature
├── AsteroidPrs.py                # interactive: pressure
├── AsteroidIso.py                # interactive: isosurface
├── AsteroidsCombined.py          # interactive: all scalars
├── Data/                         # VTI timesteps go here (gitignored)
├── docs/
│   └── MeaningOfDataAsteroid.pdf
├── media/
│   ├── asteroidRendering.gif     # preview embedded above
│   └── asteroidRendering.mp4     # full video
├── requirements.txt
└── README.md