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Soldier's equipment jittering on large terrains
Acknowledged, WishlistPublic

Description

Soldier equipment is jittering when placed more than 30 kilometers
from (0,0,0) position.

This is almost certainly a problem with equipment's position
stored as single precision floating point numbers
( see additional information ) {F24348}

Details

Legacy ID
4058708648
Severity
None
Resolution
Open
Reproducibility
Always
Category
Engine
Steps To Reproduce
  1. Load some large terrain ( 50 km x 50 km )
  2. Put armed soldier in NE corner
  3. Observe his rifle in 3rd person view ( when rifle is put down using Ctrl-Ctrl and soldier is playing idle animations )

Or :

  1. Load a mission attached in a file Jittering.VR.zip

( soldier is placed in position (47k,5,47k) ).

  1. Observe his rifle in 3rd person view ( when rifle is put down using Ctrl-Ctrl and soldier is playing idle animations )

Or :
You can also look at this video :
http://www.youtube.com/watch?v=wug0pnApRys#t=201
It is particularly visible from 4:00 to 4:19.

Additional Information

In short : object positions are (usually) represented using
floating point data types ( google for IEEE-754 on wikipedia ).
The thing with floating point data type is that when the
numbers are big, they lose precision.

In computer graphics this starts to occur when object position coded in single precision floating point is more than 30 000 units ( usually meters ) from (0,0,0) point.
And it starts to look like the position of the object is "quantified".
Look at the before mentioned video at 4:05 - the rifle looks like
it moves for a certain number of centimeters every frame - its
movement is quantified.

Event Timeline

Szelf edited Steps To Reproduce. (Show Details)Jul 16 2014, 12:52 AM
Szelf edited Additional Information. (Show Details)
Szelf set Category to Engine.
Szelf set Reproducibility to Always.
Szelf set Severity to None.
Szelf set Resolution to Open.
Szelf set Legacy ID to 4058708648.May 7 2016, 7:00 PM
Szelf added a subscriber: Szelf.May 7 2016, 7:00 PM

fixed spelling

Certainly large terrains seem to exacerbate the problem, but I've noticed weapons and accessories moving on stock terrains too.