How to set the rotate center to be the center of the object iI want to rotate? the cursor is at world origin, and I want to rotate, move, scale an object, but when I press the rotate/move/scale/ button, the rotate/move/scale center is at the world origin, the object I want to move is far away from world origin, how to set the rotate/move/scale center to be at the center of the object????

blender 2.81
The answer is to go to the Object menu, select Transform and then click on Origin to Geometry. This should solve your rotation and scaling problem.

It would also be good to apply scale and rotation to your object. (For the sake of future editing.) You can do this by going to object > apply > scale &amp; rotation.