The bar on the left spins from its center.
The bar on the right spins from its edge that has set position to the blue ball.
The bars length+width can be adjusted in the appearance tab.
The bar can be used as a sensor to detect other sprites within a certain distance and direction.
Like acting as feet so a sprite can only jump if its feet (Raycast) senses touching other sprites
Here is a link to a simple Ready project demo using the “RAYCAST” bar.
The RAYCAST extends from the eye’s center to just below the eye.
When the JUMP button’s tapped, the eye jumps. The eye only jumps if the red bar sensors touching the ground sprite.
This is this sprite i made that Ready user’s can use as the Raycast.
I made the sprite so software regards the sprites center as it’s blurred bottom edge.