[4.15]Breakpoint bugs right click drag

1-place a breakpoint inside a blueprint

2-run the game in a PIE window.

3-when the editor pauses because reaches the breakpoint and focus on the marked node, try to drag with right mouse so you can see other nodes. Then you will notice that you can not drag anymore.

4-stop the execution. try to drag again . you cant. you must restart the editor.

Hi DonFrag,

I attempted to reproduce this behavior but so far I’ve been unable to get your results. This is what I did:

  1. Created an actor class BP

  2. Added a basic setup (Event Begin Play, 2 Print Strings with a Break Point on the first Print String)

  3. PIE

  4. Right-mouse drag around the Event Graph

Results: I was able to drag around the Event Graph as expected

Could you correct my steps if I am doing something wrong and/or provide a test project?

You are right.
Now i try and it works again.
4.15.1 fixed?

It’s possible. I don’t know of an exact fix that went in for this but a dev may have caught it and fixed it without logging it. Either way I’m glad it’s working for you now.

Thank you!
(I don’t know how to mark this as “solved”)

HI guys…I also been getting this issue in some form, I start the all the above mentioned steps but I get a marquee select box and can’t pan…it keeps drawing the selection box that snap to the center of the BP grid,even if I close the BP and reopen this thing repeat itself. I have tried TJ’s steps but also this thing repeats…I have to restart the editor every time this happens.

We’ve tried reproducing this on a couple different machines but we’re still unable to repro. Would anyone having the issue be willing to post their Dxdiag (system specs)? Maybe there is something hardware/software related you all have in common that could be causing the issue (resolution, driver, etc).

I’ve found that this can be easily reproduced in 4.15 on my end with these steps:

  1. Create a touch/click event in some actor

  2. add a “Print String” node off of event

  3. toggle a breakpoint in the “Print String” node

  4. Run game in PIE

  5. Click on actor , which will trigger event and halt at break point

  6. Click “stop” in the blueprint editor while breakpoint is still triggered

  7. Mouse drag stops workingin blueprint editor

After that, I need to re-play the game and stop without triggering breakpoint for functionality to come back.

Attaching my dxdiag[link text][1]

Hi scyfris,

I attempted to reproduce this following your steps but I was unable to get your results. I was able to drag around the blueprint editor correctly.

I noticed in your dxdiag that your graphics card driver looks to be out of date. Maybe try updating to see if that makes a difference.

I also noticed that you are using 2 different monitor models. Sometimes that can cause odd little issues that are hard to track down. Was the blueprint editor window located on a different monitor than the editor when the issue occured? I tried both on my system but I still couldn’t get the issue to occur. Do you have another system that you can test the issue on?

Encountering the exact same issue. It’s only the right click that’s doing this for me and it always creates a selection marquee that originates from the origin of the blueprint editor’s coordinate space. Only remedy is to restart.

Came across this thread while searching for a solution to this very annoying bug. Started having this issue recently on a new project, and was bummed to see no workaround. I became determined with finding some workaround to avoid having to restart, because that’s such a time waster.
I think I found one.
Turns out it is related to ‘use mouse for touch’ or something to do with touch emulation. I think what causes our bug is the game getting stuck in that mode, which may explain why it happens so much when using breakpoints.
So, long story short, my workaround is to relaunch the game (in PIE, in my case), and use the UI exit button to close it (or exit in console).

Hope this helps someone!

It happened to me too. (UE4.18.2)
Place a button in Widget Blueprint and make “On Pressed” event handler, place breakpoint on it.
While playing in editor press the button to activate the breakpoint.
after stopping PIE right click dragging doesn’t scroll my widget blueprint, but only make dotted rectangle uselessly.
(I guess it’s because the button doesn’t get mouse up event)

This is how I resolve it.
Place a breakpoint on BeginPlay Event in Level Blueprint, Play in editor and it activates breakpoint and then stop PIE. right click dragging goes back to normal.
I hope it to be fixed soon.

It happened to me too. 4.18.2

I have this behaviour in 4.21.1 and 4.21.2. And after the drag, the mouse cursor jumps back to where the selection began.

I’m trying to get iOpus to go through a website (I’m a bit of an n00b but it’s going ok so far) but I’m not sure how to code the movement for a mouse clicking and holding on a slider (on a flash display) and pulling across the screen.

Thank you for any help you can give me.

no response.

should- I need to start a new thread?

It seems that you’ve necroed a 3yo thread, and with something utterly unrelated to boot. The OP is about dragging breakpoint nodes. Nothing to do with any kind of movement.


Start a new thread. And please describe it with more detail. It is not clear at all (to me, at least) what is going on and what you’re trying to achieve.

You’ve inserted link in a strange fashion - quite similar to what spam bots do, making me think you want people to follow it for some potentially nefarious reason. Hope I’m wrong.