Light bloom is done with multipass blurring. First the image is downsampled 5 times and blurred into a new image half as big using a 6x6 filter. Then each downsampled image is blurred again and added back to its parent
using a 3x3 filter. Finally, the half-size image is blurred and mixed with the original image.
It's cheap! About 80 texture read operations per pixel total.
(See alt. text for video explanation. Or see https://learnopengl.com/Guest-Articles/2022/Phys.-Based-Bloom .)
🧵 14/N
#BubbleUniverse
Kernel Bob :progress_pride:
npub1qp…qjtng
2026-02-21 20:14:10 UTC
in reply to nevent1q…jms4
Author Public Key
npub1qp89j2arjdptmcyh2lnddx4jfmd8kpm5xrfrec5ytr8hjpppx4aqgqjtngSeen on
wss://relay.momostr.pinkPublished at
2026-02-21 20:14:10 UTCEvent JSON
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"content": "Light bloom is done with multipass blurring. First the image is downsampled 5 times and blurred into a new image half as big using a 6x6 filter. Then each downsampled image is blurred again and added back to its parent\nusing a 3x3 filter. Finally, the half-size image is blurred and mixed with the original image.\n\nIt's cheap! About 80 texture read operations per pixel total.\n\n(See alt. text for video explanation. Or see https://learnopengl.com/Guest-Articles/2022/Phys.-Based-Bloom .)\n\n🧵 14/N\n\n#BubbleUniverse\nhttps://assets.chaos.social/media_attachments/files/116/110/419/751/946/519/original/b7a25b6ce85db695.mp4\n",
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