title: How do you rotate a sprite based on mouse position?
body: <p>Basically, I have a sprite that I render using SDL 2.0 that I can rotate a variable amount around a center orgin point of the texture clockwise using <code>SDL_RenderCopyEx()</code>. I want to rotate it based on the mouse position by using the angle x between my physical slope line and my two straight lines based off of my base line. The base line I'm talking about can be represented mathematically as x = orgin_x, where orgin_x is the rotation orgin. The other line is a segment along the baseline that connects the horizontal line end point to the orgin_x point vertically. With the angle to the mouse cursor being the one I want to find to rotate my character.</p>
  
  <p>Please no complicated math symbols. I would rather the formula be posted in C-style format, and please explain the logic behind the math so I can maybe understand what's happening and fix similar future problems if needed.</p>