Anti-X-Ray exposed blocks

[PeriodicSeizures]

Description

This is a feature for X-Ray to deal with servers utilizing Anti-X-Ray. This is not a bypass, but rather a band-aid that makes X-Ray not outright useless on these servers (#860).

Findings

When X-Ray is enabled and the feature 'Show exposed' is toggled to enable, sometimes nothing changes. Disabling and enabling X-Ray seems to show the changes.

BlockUtils.canBeClicked is what is currently being used. Should fences, leaves, and other non-solid blocks be considered? Currently only air, water and lava are the primary exposed blocks. I left some comments and unused code that shows what I mean in reference to some non-solid blocks when initially testing.

Transparent / non-solids

X-Ray disabled

X-Ray enabled

[CLAassistant]

All committers have signed the CLA.

[Alexander01998]

Hey @PeriodicSeizures, thanks for the pull request!

I've tested out your changes on a local Paper server with the anti-X-Ray option enabled, and it seems to be working well.

Based on my testing, it seems that Paper considers any block that isn't a full opaque block to expose ores placed next to it, even if the ores aren't actually visible. I've attached screenshots below to show what I mean:

X-Ray disabled

X-Ray enabled

As you can see, even though the lava, the closed iron door, and the front-facing birch stairs obscure the diamond ores from view, anti-X-Ray doesn't hide these ores from X-Ray. Only the ones covered by full blocks get scrambled.

I've changed the code to match Paper's behavior, by using the isOpaqueFullCube() method to determine whether a block should be considered exposed or not, instead of maintaining a separate list of "exposing" blocks.

I've also gone ahead and merged the pull request. Thanks for your contribution!