[MPlayer-dev-eng] Direct3D OSD discussion

[Georgi Petrov]

> The priv->locked_rect is locking a surface the size of the playing video
> , and the local locking is for the size of the display.  So in this case
> it is not a 'shadow' of the other lock, as the parameters are different.
>

Yep - there's real problem. I mean just "name shadowing". Never mind.

> Now I want to answer all your questions in one post...  Aaaarg
>
>> What's C "speed policy" about such declared pointers inside the for
>> statement? Would it be better this this way (speed wise):
>
> Should be non as its just a cast to make the compiler do the correct
> address calculation in the loop

I means that the both code snippets translate into the same ASM
instructions, right? I hope the compiler doesn't do something
dynamically for each from iteration when the pointer is declared
inside it.

> Yes, but pitch is guaranteed to be greater than width, so it is correct.
>  Otherwise you would have to loop over the clear and probably get a
> slower solution, given that memset is normally well optimized on most
> systems.

I see. The memory after each line (if pitch > width) is reserved for
cache, so you delete it as well. I'm sure there are no problems with
that, I just wanted to make sure you know about it.