Pick Up Physics Object Tutorial Issue

I found out if you check “Constrain Rotation” in the “Grab Component” node, and pick up the object for 3 seconds or more, it will not fall when you let go, hovering in mid air.
If you pick up the object and let go within 2 seconds it falls just fine.

Even if “Constrain Rotation” is not checked, if you pick up the object, lets say a cube, and have one edge of the cube touching the ground and hold it there for 3 seconds or more, it freezes in that position.

Seems like if the physics object is not moving for more than 3 seconds it becomes unaffected by gravity.

Tutorial Link:

I found a workaround to this. After the “Release Component” node, put an “Add Impulse” node such as the one in step 8. of the tutorial, but change the impulse value to 0.

Hi ShenmaKid,

Thank you for bringing this to my attention. I hadn’t noticed this problem with the setup. I’ll be investigating the issue further, but in the meantime your solution of adding a impulse seems to do the trick.

Okay, so I found out what is going on here. When a physics object stops all movement, it is put into Sleep Mode by the engine. This is to improve performance. To have all physics objects awake at the same time could be quite heavy.

Instead of using an ‘Add Impulse’ node, the best way is to use a ‘Wake Rigid Body’ node. This just wakens the physics object in case it happened to enter sleep mode.

Thanks again for the heads up. I’ll make sure to update the tutorial with this info.