This python script and notebook generates sun glitter distribution on Cox-Munk random sea surface slopes. Daughter rays are saved to inspect more details on the scattered daughter rays and intercepted wave facets (if user specifies save_fp in the notebook/command line). Examples of saved daughter rays are provided.

The notebook Cox_Munk_wave.ipynb contains a step-by-step guide and mathematical theory on constructing a random sea surface slope to ray tracing to the simulation of glitter on the cox-munk surface. Do follow this guide for a systematic procedure on sun glitter simulation. The figures and theory in the notebook are obtained from Preisendorfer and Mobley (1985):

Preisendorfer, R. W., & Mobley, C. D. (1985). Unpolarized Irradiance Reflectances and Glitter Patterns of Random Capillary Waves on Lakes and Seas. Monte Carlo Simulation. NOAA Technical Memorandum ERL PMEL-63.

Alternatively, one can also run the python script ray_tracing_utils.py for command-line interface, where user can specify:

• --solar_altitude: solar_altitude (angle in deg from the horizontal)
• --solar_azimuth: solar_azimuth (angle in deg from the i axis (along wind direction))
• --wind_speed: wind speed in m/s
• --n: order of hexagonal domain
• --iter: number of parent rays to seed
• --save_fp: directory on where to save the daughter rays
• --camera_altitude: camera_altitude (angle in deg from the horizontal)
• --camera_azimuth: camera_azimuth (angle in deg from the i axis (along wind direction))'

See -h for help and details on input

Sun glitter distribution at varying solar altitude, azimuth and camera altitude and azimuth.

Wind speed: 1.0 m/s

Wind speed: 5.0 m/s