title: Finding Points in a Rectangle or Circle with mysql
body: <p>I have a mysql database table with a list points with their Co-ordinates (x,y)</p>
  
  <p>I want to find the list of points which fall inside the rectangle. This would have been simple had any one side of the rectangle been aligned parallel or perpendicular to any axis. But is not. Which means the rectangle is rotated.
  I also have to find the points inside a circle.</p>
  
  <p>Known Data for Rectangle
  -Coordinates for all the four points
  Known Data for Circle
  -Co-ordinates for the center and the radius.</p>
  
  <p>How do I query the mysql table to find the points falling in the rectangle and the circle?</p>
  
  <p>If it matters then the front end I am using is PHP.</p>