CesiumGS / CesiumGS/cesium

Objects with translucent classification are rendered above all other translucent objects

Open
#9,419 5 comments 0 reactions 0 assignees View on GitHub
category - classification category - graphics type - bug
Dominant language
JavaScript
Stars
15.8k
Forks
3.9k
Avg merge
4d 6h
Merged PRs (30d)
34

Description

Sandcastle example: [link](http://localhost:8080/Apps/Sandcastle/index.html#c=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)

Browser: Firefox

Operating System: Linux

@lilleyse found this in #9399 - from a comment in that PR:

> The translucent classification framebuffer is always rendered above all translucent objects in the scene. I don't think this is fixable without some major changes to the approach. GlobeTranslucency doesn't have this problem because it renders classification to a framebuffer first and then creates a derived command for each TRANSLUCENT command that applies the classification. I.e. classification is not applied as a screen-wide post process.

![f](https://user-images.githubusercontent.com/31491650/110488150-36692700-80bc-11eb-9792-594fd426f1f1.gif)

Contributor guide

Open the contributing guide

Research direction

Start by reproducing the issue with the linked Sandcastle example in Firefox on Linux. Read the referenced discussion in issue #9399, then compare translucent classification with the GlobeTranslucency framebuffer approach described there. Done means translucent classification respects depth ordering instead of rendering above every other translucent object.

Written by the indexing model from the issue text.

Assessment

Tech stack
javascript
Domain
computer-graphics
Issue type
Bug
Difficulty
5/5
Estimated time
Over a week
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
25/100

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.