   How to know if mouse is over 2D Quad??
  i am drawing a 2D quad and i need to know if the mouse pointer is anywhere on this quad. is there a basic windowing command or check to do this? i am already using glReadPixels somewhere else in my program for something else so i need to use something different for this. what i want to do is, is when the mouse is over the quad, then it will change color and i can then move the quad with the mouse back and forth when pressing down the left mouse button... any ideas or suggestions? thanks in advance.. 
bool UI_PointInRect(vector2 max, vector2 min, vector2 p) {if( (p.x >= min.x) && (p.x <= max.x) &&(p.y >= min.y) && (p.y <= max.y)    ){return true;}return false;}