Triggering UI button onmousedown, without waiting for mouseup event?

Is there any way to make the UI.Button Onclick event to activate when pressing the button without releasing it?

If not, what should be the correct way to emulate the behavior i’m specifying here?

I’m doing a small game that relies on pressing buttons in a UI. However, since they move/rotate, sometimes you feel you’ve pressed it, but the MouseUp event happens when your click is no longer raycasting, and then it doesn’t count the tap.

Any way to make the UI Button onclick event to fire on MouseDown instantly?

OnClick only triggers on mouse up, so you can’t do it that way. What you can do is add a script of your own to the button that implements the OnPointerDown method, then raise your own event from there.

You can use EventTrigger component and there PointerDown trigger.