What does -> mean?

[nukes]

I am trying to learn SDL so I can make a real go with cpp, one thing I'm stuck on right now is the -> operator in the function calls, what does it mean? I get the feeling this is something simple enough, but I just haven't been able t find information on it. Its used for stuff in the gfx calls etc.
ok, i've found this:
expr1 -> field: returns the value of field in the structure pointed to by expr1.

So expr1 is a pointer to a struct, and a field is just one of the variables in it? is that right?

[strangerstill]

a->b is synonymous with *(a.b)
it's just syntactic sugar, like a[b] is *(a+b)

[Martee]

Close ... it's synonymous with (*a).b

[nukes]

dgfh.
so screen->format->BitsPerPixel
means format is a class with the varisable bitsperpixel. Screen is a class with format included in it as well?
Is that right?

class display {
public:
int bitsperpixel;
}
class surface {
public:
display format; }
surface *screen;

Is this the right idea?
(ignore the syntax errors I am still learning and want to check I get THIS idea.) Thanks for your help.

[Martee]

Yes, except that in the surface class, format would be a pointer, not an actual display object. With the code you posted, bitsperpixel would be accessed like screen->format.bitsperpixel. If format was a pointer, then it would be screen->format->bitsperpixel.

[strangerstill]

Oops!

(it was late and i was tired...)

[nukes]

Right, thanks, I was just confused by the syntax. Now I may start to make some progress.