[MC-63179] Clouds move with the player

This is made easier to see when viewing terrain that reaches above cloud level (the seed "14w29b" has savanna M near spawn).

Look at where the terrain intersects with the clouds. Then, fly up and down. The clouds move up and down as well. The clouds also move to the side when the player moves to the side.

(Partial) code analysis by @unknown can be found in this comment.

Linked issues

is duplicated by 5

MC-63767 Cloud Rendering Error Resolved

MC-68095 Clouds height change with the player's height Resolved

MC-70491 clouds change their hight when you go up or down Resolved

MC-146658 clouds raise or lower when the player does. Resolved

MC-157038 Cloud particles move with players y motion Resolved

Attachments

Comments 16

kumasasa 2014-07-27T09:53:31Z

~~Cannot confirm.~~

Christie N 2014-07-30T20:37:20Z

Picture of the bug in action.

kumasasa 2014-07-31T00:17:48Z

Confirmed _{should've read the bug description better}

pbilk 2014-08-18T23:06:05Z

I don't like the moving feature, well at least the side to side, the up and down is reasonable.

mickplouffe 2014-10-18T05:17:47Z

Approuve, and its wierd. With shader its Completly ugly ..

6 more comments

marcono1234 2015-11-30T11:05:46Z

Confirmed for

15w47c

A man 2016-07-29T02:56:50Z

Confirmed for 1.10.2

Tyzoe98 2016-11-18T02:50:51Z

Happens in 1.11 too.

jonathan2520 2017-08-30T14:11:22Z

Confirmed for 1.12.1.

I actually found this while looking around in MCP; I normally disable clouds. The issue is that different parts of the world use a different far plane for their projection matrix. That doesn't just move the clip plane: depth values are scaled to match! Changing this in the middle of a scene is a big no-no. It doesn't have too much of an effect because most depth values are concentrated near the camera, but with geometry at the far end you'll definitely see it. Decrease your render distance to make the effect more pronounced.

The far plane distance is the render distance multiplied by:

Thing	Coefficient	Notes
Sky	2	Doesn't write depth.
World	√2
Clouds	4
Hand	2	Clears depth buffer so it's always in front.

Just use 4 for everything if that's what you need. Move it to infinity or beyond. Really only the near plane matters for depth resolution. The nearest possible far plane in Minecraft at 32√2 provides only 0.11% more depth resolution than a far plane at infinity. There's really no benefit.