Circle view indicator on OpenGl in Qt 5.2?

Question

Qt

Good Friday, dear Khabrovites!
First, I'll describe the problem.
I am a fourth-year student at MSTU MIREA and at the same time I am studying at the military department. So. They were asked to write a program that emulates the operation of the all-round indicator (maybe you remember the TV magazine "Pun" - there, before each series of "Cool Dive", a man pulls out a tuft of hair from himself, sitting near just this indicator.).
I'm actually a Web programmer, so the skills to create desktop applications are limited to academic, very mediocre knowledge. In my life, I programmed with Qt only 3 times, and then - simple laboratory for the university. I last tried to learn C ++ about two years ago and by now I have completely forgotten it.
I drew this very locator using OpenGl (so far without any functions). At the moment, it is a round display, in which an arrow moves in a circle, which "updates" the data on the screen - passive interference and draws range and azimuth marks.
Now actually to a question. I am not familiar with the specifics of developing desktop applications, and even more so I know little about Opengl. And the problem is this: the antediluvian Pentium 2, Pentium3 are on the pulpit. Is it possible to make the program not slow down on them? And if so, what can be done for this by code (link to the repository just below).
And also I ask you to look at my code (which, as I suspect, is complete crap) and, perhaps, give some advice on implementation, suggestions for optimization, point out errors. Perhaps you can recommend some useful literature on the topic.
Thank you very much in advance.
PS I'm writing under Ubuntu Gnome 13.10, but it should work fine under Windows too.
Link to the repository

Answer 1

Regarding the processor load and the rendering algorithm, I can recommend a fragment from the book "Yuri Shchupak. Win32 API Efficient Application Development".
There, on page 527, they describe a "software simulator", and on pages 539-540 an example of accelerated rendering. I understand that you need opengl, but you can still understand the drawing algorithm on the Win32 API.

Answer 2

On Windows, the vidyahi should have OpenGl support, and Qt itself should be built with OpenGl support, by default it is built with Agile, and these are terrible brakes.