Re: GDI+ take 3

[Eli Zaretskii]

> From: Juan José García-Ripoll
>  <address@hidden>
> Date: Sun, 19 Apr 2020 22:08:06 +0200
> 
> Folloup on the previous studies. Note that I am using emacs on a 64-bit
> machine, not 32 bit. So I am unable to comment on Juanma's statistics or
> Eli's more recent build. However, I hooked into IMAGE-ANIMATE-TIMEOUT
> and it confirms what I suspected: the load times surpass the scheduled
> time of the timer.
> 
> The image that was supplied by Alan has a nominal delay time of 0.03
> seconds between frames. Emacs 26.3 takes about 0.14 seconds on average
> to load each frame of the gif file, using giflib. Emacs 28 as I built it
> from git source right now, takes 0.3 seconds with giflib and a time that
> grows from 0.01 up to 0.16 seconds (probably because frames have to be
> read sequentially, there is no index).

I see similar timings here.

I wonder why the times go up with GDI+, but not with giflib.  Maybe
the answer hides in what you say by "there's no index" -- what do you
mean by that?

P.S. Your test code allowed me to find and fix a bug in how images are
loaded natively, now fixed in the repository.