Search in
Sort by:

Question Status:

Search help

  • Simple searches use one or more words. Separate the words with spaces (cat dog) to search cat,dog or both. Separate the words with plus signs (cat +dog) to search for items that may contain cat but must contain dog.
  • You can further refine your search on the search results page, where you can search by keywords, author, topic. These can be combined with each other. Examples
    • cat dog --matches anything with cat,dog or both
    • cat +dog --searches for cat +dog where dog is a mandatory term
    • cat -dog -- searches for cat excluding any result containing dog
    • [cats] —will restrict your search to results with topic named "cats"
    • [cats] [dogs] —will restrict your search to results with both topics, "cats", and "dogs"

Editor units accuracy

Everytime I use the exact numeric values for rotating or scaling an object the editor changes it a bit. If I type 10 it ends up like 9.1314941... Does it matter or I should not pay attention to it?


Product Version: Not Selected
more ▼

asked May 29 '14 at 10:31 AM in Bug Reports

avatar image

13 6 8 11

avatar image Nick Darnell ♦♦ STAFF May 29 '14 at 03:22 PM

Hmm, where is that happening, just in the level editor? The number should only be different than what you enter if the number can't be represented as a floating point number due to numerical imprecision, which that much of a change definitely is not.

Cheers, Nick

avatar image Nick Darnell ♦♦ STAFF May 29 '14 at 03:38 PM

For rotation, I wouldn't worry about it. What the editor is doing when you enter a new value is it's creating a new delta quaternion rotation and applying that, and then it extracts the euler angles and sets those to the rotation value we save and you see. That's likely what you're seeing, due to the way quaternion math works, the euler values may not look at all like what you had before after the new rotation is applied, but it should still represent the same rotation.

We've got some squishy plans that might improve the user experience in the future, like storing the user entered rotation. Out of curiosity what numbers did you have for the rotation?

For scale though those values should remain the same, unless you have the scale locked, which then it effects the other values, scaling them up by the same ratio.

avatar image Fungy May 29 '14 at 06:45 PM

Yes, this happens only in the level editor to me. After quick tests it turns out this happens only with rotation values, the scale and move is ok.

This happens with numbers: 3,9,10,11,14,15,16,17,18,19,20... almost with every number.

I just want to be sure this is normally and doesn't affect the light system or anything else.

Anyway, here how this looks (sorry for a big picture):
alt text

avatar image gmpreussner STAFF May 29 '14 at 03:37 PM

Fungy, I am unable to reproduce this. Can you provide exact repro steps?

avatar image Fungy May 29 '14 at 06:54 PM

Well, I posted a screenshot above and here's repro steps:

  1. Add a static mesh on the level

  2. In the Transform section enter a rotation value, for example 3,9,10,20,40

  3. After I press "Enter" the resultin value is not what exactly what I typed (10 is 9.99999 or 50 is 49.999996)

(comments are locked)
10|2000 characters needed characters left
Viewable by all users

1 answer: sort voted first

I was able to repro. The difference you're seeing are floating point rounding errors that occur when converting your input value to a quaternion and back. We are already aware of this problem and planning to adjust this part of the code so that the transformation data is stored in a way that does not alter the user's input.

For all practical purposes, the difference should not cause any problems, although it may trigger some OCD reflexes in some :)

more ▼

answered May 29 '14 at 08:36 PM

avatar image EvilReFlex Jan 11 '19 at 12:14 PM

Still have the problem in 2019 with UE 4.21

avatar image katherineyer666 Feb 04 '19 at 01:16 PM

I think I am also facing this issue. Did you get any proper solution?

(comments are locked)
10|2000 characters needed characters left
Viewable by all users
Your answer
toggle preview:

Up to 5 attachments (including images) can be used with a maximum of 5.2 MB each and 5.2 MB total.

Follow this question

Once you sign in you will be able to subscribe for any updates here

Answers to this question