I have several dictionaries that juggle values between them, so I want to manage the lifetime of the contents myself. But when closing the program I rather empty all the dictionaries. I had a code looping the keys and then getting the values and then freeing the values. that resulted in mem leaks. But I found I can just iterate the values directly and free them. I just haven't used dictionary before. Anyway it is solved.

For graphics card I have Nvidia GFX 860M or something like that. Laptop. I didn't see any notes about maximum size in the OpenGL documentation. Will continue on this issue tonight.