Anyone else noticing a random double click while drawing in sketch mode?

[BeeAmaker]

This issue could be my mouse, but everything has been working fine up until right after adding the Dark theme. 

Every now and then when drawing in sketch I seem to get an auto-double click, for example, I will start a line and finish the line only to find that I have actually drawn 2 segments shown in the picture. I only click once to start the line and clicked once to end the line so not sure what is going one.

Sometimes that little segment will be arced, indicating a press and hold. These segments are small, a lot of time less than 1mm. I don't always spot them until I start laying in dimensions and constraints. 

I have also noticed weird things while laying dimensions. Example is a point immediately de-selecting after being selected. 

I don't have a different mouse to try at the moment, and I haven't seen any other software on my machine doing anything weird. I also haven't had any issues while in other modes like 3D - except Extrude. Again sometimes things will de-select right after selecting them, or areas will get selected simply because the mouse passed over them.

Now that I think about it - I have seen anomalies when drawing lines in Schematics. Sometimes when starting a line I will get a short segment at the beginning. Note, the little segment only occurs when starting a line, or continuing a line (multiple segments) I haven't seen any anomalies when ending a line.

Just curious if anyone else has been seen odd things also before I buy a new mouse.

 

[g-andresen]

Hi,

An effect that has been known for several years but whose cause has apparently not (yet) been discovered.

Günther

[crueby1]

I have been seeing the same thing for a long time, happens at random. Very annoying.

[BeeAmaker]

Well... I guess I'm glad it's not my mouse ?? lol 

I've been using fusion for a long time - wonder why I'm just seeing this now.

[dsouzasujay]

hi @BeeAmaker @crueby1 @g-andresen 

Thanks for the detailed explanation and for sharing your observations, that level of detail is genuinely helpful.

I want to be transparent here, issues like this are unfortunately very difficult to fix without reliable reproduction steps. I have looked into similar reports in the past, but without consistent, repeatable steps, it’s extremely challenging for the development team to identify the root cause and implement a fix.

At the moment, we are not able to reliably reproduce this behavior internally, which makes it hard to determine whether it’s tied to input handling, timing, graphics/UI interaction, or a very specific state in the application.

If at any point you (or others experiencing this) are able to:

• Identify specific steps or conditions that consistently trigger the issue

• Notice whether it happens only after certain actions (theme change, long sessions, specific tools, etc.)

• Capture a short video that shows the behavior from tool start to anomaly

that would significantly increase our ability to investigate and address it properly.

Even partial patterns or “it happens more often when…” observations can help narrow things down. And if you do happen to figure out a workaround or a reliable trigger, please do share it here, it would be valuable both for us and for other users.

We appreciate you raising this and discussing it openly. We are definitely willing to look into it further, we just need enough signal to give the development team something actionable to work with.

[BeeAmaker]

Ill report back any additional info I collect. thanks

[crueby1]

@dsouzasujay, 

Okay, I got at least one way to reliably make this happen! I am on a Windows 11 desktop PC, running latest Fusion.

Here it is - have a sketch open with something in it, does not seem to matter what. Create a line (type 'l' or the menu, either works), and click on a point in the sketch, to add that line to the existing sketch item. You have to start the new line at an existing point, doing it as a new standalone line does not make it happen. Now, the key is to move the mouse right away as you click the point. If you click on the point, pause, then move the mouse, it works correctly. If you move the mouse too quick, it makes a short line segment then drags out to the new mouse position from there. Sometimes the short segment is a straight line, sometimes it is a tiny arc, must depend which direction you move the mouse. My guess is that it is seeing the movement before the 'up' event from the mouse button, and is creating a segment there.

Attached is a short video showing it on my system. And before anyone asks, no, I can't make the recording move slower, the bug appears to only happen with moving the mouse quickly after the down event on the mouse. Hope this sequence helps you solve this one! As a former software/firmware engineer, I am aware how you need to be able to reproduce it reliably - this definitely works every time.

Chris

[BeeAmaker]

I wonder if DPI/Response time has anything to do with it. I'm using a Gaming mouse which has a high response time. Also, wired vs wireless, if wireless - then maybe battery condition might affect it. 

Click-hold-drag = arc is expected behavior. This only happens if the start point is on an end point. Click-hold-drag from any position on a line just gives me a line perpendicular to that line segment. Click-hold-drag at any point on an arc gives me a straight-line tangent to that arc. So, it makes sense if you move the mouse before releasing the button you will get a short segment, Or like you stated, if the software isn't recognizing the release instantly.

I can do this slow also, if I click-hold-drag I will get a line. When I release it will create a point at that mouse position and a new line I can drag out to any position and click again to create a new point. This does seem to be what is happening, only supper fast and even though I have released the mouse button before dragging. 

However - I have seen this happen while drawing nets in a schematic. Using the method described does not replicate it while drawing in a schematic.

I have updated my mouse driver, so far, I have not seen this behavior again, but I haven't drawn much lately. My next step is to use the mouse wireless vs wired and fully charged vs almost dead with wireless.

[crueby1]

@dsouzasujay, @BeeAmaker,

I agree that the hold/drag function should create a line, but in cases like this it is just WAY too sensitive to any movement during a fast click. The times I am seeing it, I am just doing a quick click down/up, not a down and hold for any intentional length of time. It seems to be taking the slightest mouse move during that down/up time as an intentional move, when just the pressure of my finger on the button could be moving the mouse a pixel or two, and creating a dragged line. In my case, I am using an Evoluent Vertical Mouse, not a super fast gaming mouse. If the code could discard any movements during a quick down/up click it would solve the issue - there is no way anyone could do an intentional move to a desired location in a few milliseconds like it is doing.

[dsouzasujay]

Hi @crueby1 ,

Thank you for the detailed investigation and for sharing the video and clear reproduction steps, that was extremely helpful.

I have logged this internally as a defect under FUS-230598 so the development team can investigate it further. I’ll be sure to update this thread if I hear back with any progress or additional questions from the team.

Thanks again for taking the time to document this so thoroughly, it’s very much appreciated.

[crueby1]

Thanks for the update!