Hi
my pleasure to get the attention and the joining in thread of all you!
All the info showed by you are very important for a beginner of Opengl.
1. Yes Opengl uses own screen dimensions and Cartesian axis, own range value for _RGB system, own coordinates to map images to use as sprite or as textures.
2. (i dunno if it is different in other languages of programming) but in QB64 you can use Opengl commands only into _GL() sub
3. In running mode _GL sub runs about at 60FPS (frequency or rate for second and NOT frame for second)
4. So you can imagine that you cannot make I/O or calculations or loops or _delays in it except for those that don't break this its nature to run always fast. (so you get that without a blocking loop you can use Inkey$ or _Keyhit or _Keydown in _GL sub)
5. Ashish has already posted an alternative solution to the problem of translate the coordinates between Screen setting and Opengl metric system. Other 2 solutions are A) that used in the code that translates on fly at need the coordinates or
B) set the Screen coordinates equal to Opengl cohordinates by using WINDOW command of QB. For example
A bit more complex is to use a matrix (bidimensionale array) that stores value already calculated. It is evident when you try to make a Plasma code into Opengl.
5. The screen of Opengl is always void! This means that all those commands and techniques that relies their own efficacy on the information stored in graphic memory (think about point() or screen and all the others commands) are without importance here. The easy workaround is to store those informations into a matrix of 2 dimensional array) of unsigned long for a 32bit color screen.
@Ashish your Opengl tutorial is very good, but as the general tutorial, it doesn't cover all the features of Opengl commands nor all Opengl commands nor how using Opengl to do.....
Nevertheless I find it not only for beginners because it is plenty of informations.
As I said you some time ago, if it is your interest and your will, you can make video tutorials or a more step by step tutorial on Opengl.
@bplus Yes
1. surely the Opengl subs to draw pad can be unified.
2. Ai Vs human is more interesting I'll do an algorithm
3. Wiki is so much void about _GL commands
4. Easily the standard graphic mode can be stripped out to show the only Opengl version and the beginner must be focused to see the difference between this mode and standard mode to do graphic.
