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"

Why does vertex painting on a large mesh cause my frame rate to drop?

link textHello,

I thought it would be nice to test the new ue4 out by rebuilding my project that I was making in udk to ue4. Only when I wanted to start vertex painting the terrain (which is an imported static mesh) I noticed that everything became very laggy, the fps went down from 56~ to 18~ fps and that was only by hovering my mouse above the terrain, when I started to paint the engine froze for about a minute without even seeing what you painted, only when it stopped freezing could you see what you had painted. I did this a few times until I opened the task manager and saw that ue4 was using 12gb of ram (and I think it could go even higher if I continued painting).

The terrain has about 7000 vertices, but I got the same problem on a mesh that had 3500 vertices, only static meshes with much lower vertex count didn't have this problem. When I painted the terrain in udk I didn't have a problem at all.

So my question is is this a bug? Does anyone else have the same problem?

Product Version: Not Selected
dxdiag.txt (62.6 kB)
more ▼

asked Mar 31 '14 at 12:13 PM in Bug Reports

avatar image

1 1 2 4

avatar image Adam Davis STAFF Apr 01 '14 at 03:43 PM

Hi st0kje,

Would you mind posting your dxdiag so we can further assist you with this? Thank you and have a great day!

avatar image st0kje Apr 01 '14 at 08:30 PM

Hi adam,

I've added the dxdiag above

avatar image Adam Davis STAFF Apr 01 '14 at 08:49 PM

Hi st0kje,

So far we have been unable to reproduce this on our end, do you have a test asset you wouldn't mind sharing so we could see what is going on? Thank you!

avatar image st0kje Apr 01 '14 at 09:18 PM

Thanks for replying! I've sorta fixed the problem, and sorta not

The terrain that I wanted to vertexpaint had quite a high custom collision mesh, I deleted it and the engine didn't freeze anymore when I wanted to paint, but I still got some dramatic frame drops when painting (cursor also disappears sometimes when painting)

I've put a link to the file beneath(terrain with custom collision), couldn't attach it cause of the 524kb limit


avatar image sayer6913 Jan 21 '19 at 01:22 AM

I'm getting this issue as well.

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

2 answers: sort voted first


Thank you for your report. We were not able to investigate this on the engine version you reported, but there have been many version changes to UE4 since this question was first posted. With a new version of the Engine comes new fixes and it is possible that this issue has changed or may no longer occur. Due to timetable of when this issue was first posted, we are marking this post as resolved for tracking purposes. If you are still experiencing the issue you reported in the current engine version, then please respond to this message with additional information and we will investigate as soon as possible. If you are experiencing a similar, but different issue at this time, please submit a new report for it.

Thank you.

more ▼

answered Oct 03 '14 at 01:55 PM

avatar image imad laggoune Aug 10 '18 at 09:21 PM

no this problem still lagging when painting in large meshs in ue4.20.1

avatar image bootstrotter Jul 04 '19 at 03:08 AM

Still lag in 4.21.2

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

This sort of happened to me, whenever i was vertex painting a large mesh i'm using for terrain, if i was still in vertex paint mode, and then hit play, fps would be super low, if i went out of vertex paint and in to object selection, then hit play, fps would go back up.

more ▼

answered Apr 26 '19 at 11:49 AM

avatar image


(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