For an archer in my recreation, I wish to calculate the launch angle to hit a degree (x,y) when fired from (0,0). The preliminary energy is thought, so I take advantage of the next method:
https://en.wikipedia.org/wiki/Projectile_motion#Angle_percentCEpercentB8_required_to_hit_coordinate_(x,_y)

The drawback is that the arrow shouldn’t be a degree and relying on the angle the archer shoots at, solely the situation of the bottom of the arrow is fixed. The displacements from the bottom of the arrow to the middle of the arrow, which is the middle of gravity and the arrow tip are depending on the angle. These displacements are of the shape (cos(theta), sin(theta)) * r the place r is a few fixed. i.e. the arrow is rotated by the intention angle round its base. As the arrow travels by the air it’s rotated round its heart to face the route it’s transferring.

How can I calculate the angle required for the tip of the arrow to hit a degree?

Example for instance (two totally different angles, base of arrow = blue, heart of gravity = inexperienced, tip of arrow = crimson):