Hi! There is this banding effect when zooming out or in fast in the Ambient Occlusion sandcastle:
Sandcastle:
The AO looks really good otherwise but this bug happens on movement only, its kind of temporal.
Just found some info here:
opened 08:24AM - 03 Feb 23 UTC
type - bug
category - graphics
category - post-processing
Here is a screen record:
https://user-images.githubusercontent.com/22176164… /216549800-9f46cdf3-7315-4673-bd00-5abf7ed2759a.mp4
Sandcastle example: [URL](https://sandcastle.cesium.com/#c=fVVtb9pIEP4rK+6LiZzFr9guJKpKcl96vUYK15MqpHRjD2R7Zpdbr03INf/9Zr02EJIWkAyzz7w8z84MuRSVJg2HLShyQQRsyQwqXq/pl9bmLAZ5+3smhWZcgFoMXPLfQhCiQSm03CjZ8ALUu94xV8A0/C1VWcwtxGnxhCj4t4ZKfwGl4fFPqdasrN4RrWpwDeB56JKFeB5OFmIhtlwUckv3ldkv7VHe1ryRlcbcWF21P6ZHxlvNVlBRVhTOEaubE4AtbanYag1C3z6wlsk3Wy8XpIE8IM0d1qtrBTMpVcEF0qsmFlILvkQipGLrTQkquCIFbPTD3OLbcg0Mw0QkL/lmLq934LRR68Yly1IybV2GFtlJRWzmxx1yqxtyRgLqkXPiU29yBIiMCtczxORP6zsuGlAVIL3vkGsuBboZkPO4c22OM4xyjjFcE2i4j9QHsc+RfdLt/lwBkhHW3Bmfe2ay1raS31HDmSyl6hCN5AVZm9sfnpD6q/lQL5f2Vn+uLOnEuYKG5/C144i9VVwZKs6xzu4+5oEUXxKn9728IB7N7Iv8+LGPOTV2z778ozLJgY0p0mjou8TIhp9Dil6ZvWGvSss0JBX2ExerG8mFbhV2Dj3QV+z21QyH9HH3NDmE+K2AJU4c+XQ3/3z38VNbqt8fvgp9Yjjr3U7k1AgtQaxQwZceQ7z4wPOOGuyVBoaTo4cvuufZPL65Zm6N6WgAKQh2X0KB3kscdDsM5t3Nas7WoJgZWd4264vtM2O4IyrOROicR6GfeQmN/HEURME4CV1yHodZFqYRTb1xmI7jKIhdEoZJ4iUB9X0PXSIvTkxFL7MVXHWz8dN0KEHq+2mY+F4WZkmcRpjQoymagtAP/DDKwiCOjC0ep1k29oIgi9MszV6nqze/yuN74yRKkyCLMASGR14YM4mSMI7HQYK0wy41Jh2nmMxPMHlsN+QtE0XOKl2CWXJzuVqV8KHWWgpc2ted9kf7zizu9iLwUQsrgmNuL3+A/B8oFqKbgLfvsENNug09cAfTSu9KuOzb5T1fb6TSpFalQ+lIA25EM8+j+xodNc2rqm+a6ejYdVrwhvDi4o2/GtyZrKrwZFmX5S1/gsXgcjpC/CtXbG7TzJ9xBZZsZ2AP/uUf1kgpnY7w59ueWsrynqmTyP8D)
Browser: Google Chrome 109.0.5414.120
Operating System: Windows 10 Version 21H2 (Build 19044.2486)
Any suggestions are welcome!
and here:
CesiumGS:main ← CesiumGS:ao-sampling-disc
opened 05:57PM - 19 Nov 24 UTC
# Description
Ambient Occlusion (AO) for geospatial data needs to produce goo… d results at a wide range of scales, without requiring the user to adjust parameters for each zoom level. This PR redefines the weight function for AO as a normalized Gaussian window, with a variance that scales with the distance from the camera.
Before this PR, the AO effect disappears when zoomed out:
After this PR, the AO effect blurs wider, remaining visible (though lower intensity) when far from the camera:
When viewing a scene from larger distances, some flickering and noise may be visible, partly due to https://github.com/CesiumGS/cesium/issues/11067. These can be reduced by setting `Viewer.camera.frustum.near` to `1.0` or more, to improve precision in the depth buffer.
## Issue number and link
Fixes #10106.
## Testing plan
# Author checklist
- [x] I have submitted a Contributor License Agreement
- [x] I have added my name to `CONTRIBUTORS.md`
- [x] I have updated `CHANGES.md` with a short summary of my change
- [x] I have added or updated unit tests to ensure consistent code coverage
- [x] I have updated the inline documentation, and included code examples where relevant
- [x] I have performed a self-review of my code
#TODO
- [x] Rework uniforms to expose loop counts and Gaussian window size
- [x] Add fallback to support variable loop counts in WebGL1
- [ ] ~Add fallback with deprecation message to support old uniforms~
- [x] Test performance, pre-compute window weights if needed
- [x] Choose good defaults
- [x] Resolve artifact at frustum boundary
- [x] Remove blur method, possibly replace with bilateral filtering
The bug is way more visible with smaller near values, like 0.01.
Hi @v12424124_34 ,
I am similarly able to reproduce the banding effect you identified in the Ambient Occlusion sandcastle using a near value of 0.01.
Are you willing to open an issue to report this? The items you provided in your posts are most of what is required Issues · CesiumGS/cesium · GitHub , please also include info about your environment.
Thanks,
Hi! Thanks, the github links I posted actually talk about the issue in detail already and it seems that its being worked on already.
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