bsrender - 3D rendering engine for Gaia DR3

bsrender - Billion Star 3D rendering engine for the Gaia DR3 dataset

bsrender is a 3D rendering engine for large star databases such as the ESA's mission Gaia DR3 data set with over a billion stars.
It generates PNG images from any position inside or outside the galaxy and can be run from the command line or cgi mode.
Direct rendering is used for every star without the use of pre-rendered frames or low-res previews.

Key features:

Generate images in JPG, PNG, AVIF, HEIF, or OpenEXR formats with multiple bit depths depending on format. AVIF encding is very slow. HEIF is supported in cli mode only (not CGI/web interface).
HDR is supported on all formats using an experimental oepn source Rec. 2100 PQ ICC profile (PNG, JPG), or in-header signaling (EXR, AVIF, HEIF). HDR is known to work with Chrome browser on M1/M2 Macbooks. HDR images on some unsupported viewers/hardware may appear very washed out or very dark
3D translations/rotations of camera position/aiming using ICRS equitorial or Euclidian coordinates. Camera can be placed anywhere in the Universe
Customizable camera resolution, field of view, sensitivity, white balance, color saturation, and gamma
Several raster projection modes are supported: lat/lon (equirectangular), Spherical (forward hemisphere centered), Spherical (front/rear hemispheres), Hammer, Mollewide
Stars can be filtered by parallax quality (parallax over error), distance from camera or target, and apparent temperature
Camera color is modeled with a Planck spectrum for the apparent temperature of each star and customizable bandpass filters for each color channel
Apparent star temperature (color) is derived from Gaia bp/G and/or rp/G flux ratios for most stars
Multithreading support with customizable number of threads
Runtime configuration can be from any combination of compiled-in defualts, configuration file settings, command line flags, or CGI QUERY_STRING (if in CGI mode). The same option=value settings are used in all of these modes

Optional features:

After aiming at target, separate controls are provided to pan and tilt away from target for maximum flexibility with aiming. Camera can also be rotated about it's view axis for desired orientation
Support for user-supplied stars. A sample external database is provided with the Sun and all stars brighter than magnitude 3 that are not included in the Gaia dataset
Airy disks provide photorealistic renderings of individual stars and clusters when enabled
Gaussian blur and/or Lanczos2 output scaling. This allows high resolution renderings to be smoothed and downsampled on a server before downloading
Anti-aliasing, helpful when combining multiple frames into videos or simulating DSLR/MILC images
Skyglow for simulating views through Earth's atmosphere
A sample html/javascript interface includes presets for a few camera targets and several common Hubble bandpass filter settings (along with typical LRGB). Also allows copy/paste settings URL for sharing links to your rendering settings

Live Demo Note: demo rendering server may not always be running due to cost

Source code: GitHub

Sample binary data files

HDR Sample renderings (will appear washed out/fuzzy on unsupported viewers):

20230707: Pleiades cluser in HDR 2000x1000 8-bit JPG (270K)
On supported viewers/hardware (Chrome browser on M1/M2 Mac) the bright stars will be very bright.
On unsupported viewers/hardware the image will appear washed out and "fuzzy".

20230707: 90 degree view of the Galactic Center in HDR 8000x4500 16-bit PNG (209M) | 16000x9000 16-bit PNG (841M)
On supported viewers/hardware (Chrome browser on M1/M2 Mac) the bright stars will be very bright.
On unsupported viewers/hardware the image will appear washed out and "fuzzy".

20230707: 10 degree close up of the LMC in HDR 3000x6000 8-bit JPG (6.8M) | 3000x6000 16-bit PNG (102.2M)
On supported viewers/hardware (Chrome browser on M1/M2 Mac) this image will have very high contrast.
On unsupported viewers/hardware the image will appear washed out and "fuzzy".

20230707: 10 degree close up of the LMC in HDR 4000x4000 8-bit JPG (6.1M) | 4000x4000 16-bit PNG (92.6M)
On supported viewers/hardware (Chrome browser on M1/M2 Mac) this image will have very high contrast.
On unsupported viewers/hardware the image will appear washed out and "fuzzy".

20230707: Sirius A and B in HDR 369x403 8-bit JPG (7K) | 369x403 16-bit PNG (680K)
On supported viewers/hardware (Chrome browser on M1/M2 Mac) this image will have very high contrast.
On unsupported viewers/hardware the image will appear washed out and "fuzzy".

SDR Sample renderings:

360 degree panorama of Milky Way with Airy disks. Includes 1.4 Billion stars from the Gaia DR3 dataset plus ~120 supplemental bright stars.
Rendered with spherical projection at 128000x64000 (8.2 gigapixels), 16 bits per color, and downsampled to 8000x4000 (155.9MB) | 32000x16000 (1.96GB)
This rendering use the Rec.2020 colorspace and may not display correct colors if your browser/os don't support colorspace conversions.
The left hemisphere is facing the galactic center, right hemisphere is facing the galactic anti-center.

360 degree panorama of Milky Way with Airy disks. Includes 1.4 Billion stars from the Gaia DR3 dataset plus ~120 supplemental bright stars.
Rendered with equirectangular (lat/lon) projection at 128000x64000 (8.2 gigapixels) and downsampled to 8000x4000 (68.3MB) | 32000x16000 (902MB)

360 degree panorama of Milky Way star density (no Airy disks)
Rendered with Hammer projection at 128000x64000 (8.2 gigapixels) and downsampled to 8000x4000 (49.6MB) | 32000x16000 (720MB)

90 degree close-up of the Galactic Center
Rendered with spherical projection at 64000x36000 and downsampled to 8000x4000 (98.7MB) | 32000x18000 (1.5GB)
Video panning around the galactic plane 3180x2160 (264Mb)

180 degree view centered on the Large Magellanic Cloud (LMC), a satellite galaxy of the Milky Way. The Small Magellanic
Cloud (SMC) is visible below and to the right. The arc of the Milky Way galactic plane is visible on the left side with Orion
at the top and the galactic center at the very bottom.
Rendered with spherical projection at 200000x200000 and downsampled to 4000x4000 (28.9MB) | 8000x8000 (118.5MB) | 32000x32000 (1.67GB)

60 degree view of the galactic center showing only stars between 1200K-1500K apparent temperature. Foreground stars are very
overexposed and have large Airy disks. Rendering only a narrow low temperature range allows us to see through much of the interstellar
gas/dust that absorbs shorter wavelengths more strongly. All of the stars in this image are approximately the same color. The yellowing
towards the center is a side effect of high star density and the rendering engine being configured to saturate overexposed pixels towards
white like a real camera.
Rendered with spherical rojection at 8000x8000 (64.5MB) | 16000x16000 (152.4MB)
or without foreground stars < 2kpc 8000x8000 (58.5MB) | 16000x16000 (138.1MB)

Comparison of a Hubble image and bsrender rendering for NGC 1783. Hubble sees much fainter stars than Gaia and bsrender does not yet simulate Hubble diffraction spikes, but
otherwise the two images are quite similar. In particular this is a good demonstration of the performance of the apparent temperature algorithm in bsrender's mkgalaxy utility.

Comparison of a Hubble image and bsrender rendering for Pismis 26.

This series below shows how narrow apparent temperature ranges can reveal different layers of detail of the interstellar gas/dust clouds.
Stars behind these clouds appear dimmer, redder, and have been assigned a lower apparent temperature by bsrender pre-processing.
Stars also tend to be older and cooler towards the galactic center. These two effects combined allow us to "see through" more of
the gas/dust at progressively lower temperature ranges.

180 degree view of the galactic disk showing only stars between 1000K-1500K apparent temperature.
Rendered with equirectangular (lat/lon) projection at 4000x2000 (4.8MB)

180 degree view of the galactic disk showing only stars between 1500K-2000K apparent temperature.
Rendered with equirectangular (lat/lon) projection at 8000x4000 downsampled to 4000x2000 (7.7MB)

180 degree view of the galactic disk showing only stars between 2000K-2500K apparent temperature.
Rendered with equirectangular (lat/lon) projection at 16000x8000 downsampled to 4000x2000 (12.5MB)

180 degree view of the galactic disk showing only stars between 2500K-3000K apparent temperature.
Rendered with equirectangular (lat/lon) projection at 16000x8000 downsampled to 4000x2000 (15.4MB)

180 degree view of the galactic disk showing only stars between 3000K-3500K apparent temperature.
Rendered with equirectangular (lat/lon) projection at 16000x8000 downsampled to 4000x2000 (17.0MB)

180 degree view of the galactic disk showing only stars between 3500K-4000K apparent temperature.
Rendered with equirectangular (lat/lon) projection at 16000x8000 downsampled to 4000x2000 (19.9MB)

180 degree view of the galactic disk showing only stars between 4000K-4500K apparent temperature.
Rendered with equirectangular (lat/lon) projection at 16000x8000 downsampled to 4000x2000 (20.7MB)

180 degree view of the galactic disk showing only stars between 4500K-5000K apparent temperature.
Rendered with equirectangular (lat/lon) projection at 8000x4000 downsampled to 4000x2000 (22.2MB)

180 degree view of the galactic disk showing only stars between 5000K-6000K apparent temperature.
Rendered with equirectangular (lat/lon) projection at 4000x2000 (19.5MB)

180 degree view of the galactic disk showing only stars between 6000K-8000K apparent temperature.
Rendered with equirectangular (lat/lon) projection at 4000x2000 (13.4MB)

Simulated naked eye night sky, 39 deg. North, January
Rendered with spherical projection at 4000x4000 (20.9MB) (new render with skyglow 2022-01-04!)
Video showing 365 days of Northern night sky in 60 seconds at 1080x1080 30fps (31.2MB)

Simulated naked eye night sky, 39 deg. South, July
Rendered with spherical projection at 6000x6000 (21.4MB) (new render with skyglow 2022-01-04!)
Video showing 365 days of Southern night sky in 60 seconds at 1080x1080 30fps (30.5MB)

Orion 4000x6000 (New rendering 2021/12/30!)

Large Magellanic Cloud with simulated IR/Vis/UV filters for enhanced color 8000x8000

Pleiades 2000x1000