[Input Bug] - When there is to many input in PlayerController some input in character are not triggered

Development Programming & Scripting
1

Reproduction:

First Download sample source:
https://dl.dropboxusercontent.com/u/70400220/Bugs/InputBug.zip

I used the 4.2.1 launcher version to create this project, but this bug should be reproducible in 4.2 source version as well.

Now run the project in debug mode, and setup break points in Visual Studio:

One here:

void AInputBugCharacter::InputSwapLeftWeapon()
{

}

And One here:

void AInputBugPlayerController::InputSwapRightWeapon()
{
}

The keybind for action are respectivly Ctrl+LMB and Ctrl+RMB.

Function in controller will always be called, but the function in character never. The odd thing is that input actions works up to PickupItem, anything after it, just doesn’t receive input. It might be problem with my setup though.

In any case here is relevelant code:

+ActionMappings=(ActionName="SwapLeftWeapon",Key=LeftMouseButton,bShift=False,bCtrl=True,bAlt=False)

+ActionMappings=(ActionName="SwapRightWeapon",Key=RightMouseButton,bShift=False,bCtrl=True,bAlt=False)
+ActionMappings=(ActionName="RandomAction",Key=T,bShift=False,bCtrl=True,bAlt=False)

Controller:

//InputComponent->BindAction("SwapLeftWeapon", IE_Pressed, this, &AARCharacter::InputSwapLeftWeapon);
	InputComponent->BindAction("SwapRightWeapon", IE_Pressed, this, &AInputBugPlayerController::InputSwapRightWeapon);

Character:

InputComponent->BindAction("PickupItem", IE_Pressed, this, &AInputBugCharacter::PickupItem);
InputComponent->BindAction("SwapLeftWeapon", IE_Pressed, this, &AInputBugCharacter::InputSwapLeftWeapon);
InputComponent->BindAction("RandomAction", IE_Pressed, this, &AInputBugCharacter::InputRandomAction);

The same issue is in Blueprints as well. When there as many as action, any input events in CharacterBlueprint are not triggered.

2

The input was behaving all kinds of erraticllly. SwapLeftWeapon’s (CTRL+LMB) listener wouldn’t fire unless I disabled listening to LMB (by changing Action name). Also, any of the Listeners bound after you bound the touch interface refused to fire, I moved the touch interface binding to after regular input binding, and RandomAction began to fire, but only if I hit the CTRL+T key twice in a row.

Odd inddeed. Could the requirement to double-tap ctrl+T to fire RandomAction (in my modified sources) be related to the viewport not having focus in the editor? Since it looses focus every time a breakpoint hit’s it would have to be tested with on screen debugging.

I would test further but, and not to be rude, I have a lot on my plate as is.

3

Hello,

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.