<div dir="ltr"> <div class="gmail_extra"> <div class="gmail_quote">On Tue, Dec 22, 2015 at 2:32 AM, Oded Gabbay <<a href="mailto:oded.gabbay@gmail.com" target="_blank">oded.gabbay@gmail.com</a>> wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">On Sat, Dec 12, 2015 at 8:06 PM, <<a href="mailto:spitzak@gmail.com">spitzak@gmail.com</a>> wrote: > From: Bill Spitzak <<a href="mailto:spitzak@gmail.com">spitzak@gmail.com</a>> > > The other filters don't range-check, so there is no need for this > one to either. It is only called with x==0. Actually, I tried to stop at this function in gdb and didn't manage to do it (using the scale demo). I then looked at the code and it seems to me that the only way to reach this function is when both reconstruction and sample kernels are IMPLUSE. That's because: 1. If both reconstruction and sample are *not* IMPLUSE, then of course we won't reach it. 2. If only one of them is IMPLUSE, than the code will immediately return the value of the function of the other kernel, which is *not* IMPLUSE. However, when I put both of them to IMPLUSE in the scale demo, the picture simply disappears *and* the impluse_kernel is still not reached. Actually, in that case, the integral() func is never reached as well. What am I missing ? </blockquote><div> </div><div>I believe at this point the calling code calculated a width of zero for the filter, and this caused all kinds of problems. </div><div>I think you are correct that in most or all versions of this code, that impulse function is never called, and it could be a null pointer instead.</div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> Oded > --- > pixman/pixman-filter.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/pixman/pixman-filter.c b/pixman/pixman-filter.c > index fbc657d..00126cd 100644 > --- a/pixman/pixman-filter.c > +++ b/pixman/pixman-filter.c > @@ -45,7 +45,7 @@ typedef struct > static double > impulse_kernel (double x) > { > - return (x == 0.0)? 1.0 : 0.0; > + return 1; > } > > static double > -- > 1.9.1 > > _______________________________________________ > Pixman mailing list > <a href="mailto:Pixman@lists.freedesktop.org">Pixman@lists.freedesktop.org</a> > <a href="http://lists.freedesktop.org/mailman/listinfo/pixman" rel="noreferrer" target="_blank">http://lists.freedesktop.org/mailman/listinfo/pixman</a> </blockquote></div> </div></div>