Optimization is a must in computer graphics applications, mainly in those devoted to real-time interaction, such as visualization and games. One possibility is to optimise everything that can be optimised, but this is in most cases a waste of time. There are segments in our applications that when optimised bring an overall gain in efficiency to our application, but this is not true for all segments.
VSPL, a component of the Very Simple * Libraries, brings a profiler which you can display on top of your application using OpenGL. There are no dependencies whatsoever, and the only requirement to display the profile report on top of the application is a function to display a string. In OpenGL you can use VSFL, another component of the Very Simple * Libraries.