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Life & fun · May 2, 2026

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Browser-based light pollution simulator using real photometric data

Hi HN — author here. iesna.eu is a browser-based ecosystem for working with photometric data: parsing standard luminaire files (LDT/EULUMDAT, IES LM-63, Oxytech, ATLA-S001), running design calculations against EN 13201 / ANSI/IES RP-8 / CJJ 45 / IES-IDA MLO, and (the part I most want to show off here) rendering real urban scenes in Bevy with the photometric data driving actual streetlight behavior, including sky-glow contribution. The Skyglow Analysis demo loads a real LDT file into a Bevy scene (Khronos Bistro test asset). The luminaire's intensity distribution…

Browser-based light pollution simulator using real photometric data launched on May 2, 2026 with 44 votes, #784 of 20,538 launches that month and more than 95% of that year's launches.

Visit iesna.eu ↗Alternativestop 4% of May 2026

In plain words

IESNA.eu is a browser-based tool for lighting professionals that parses standard luminaire data files and runs design calculations against international lighting standards. It renders urban scenes with realistic streetlight behavior, showing how different fixtures affect light pollution and sky glow in real time. Users can visualize the impact of lighting choices on their surroundings, swapping between fixture types to see immediate changes in sky brightness and light distribution on buildings.

written from the facts on this page · September 2026

From the sources

In the maker’s words, at launch

Hi HN — author here. iesna.eu is a browser-based ecosystem for working with photometric data: parsing standard luminaire files (LDT/EULUMDAT, IES LM-63, Oxytech, ATLA-S001), running design calculations against EN 13201 / ANSI/IES RP-8 / CJJ 45 / IES-IDA MLO, and (the part I most want to show…

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