[sudara]

Fixed! Sorry about that. The rustrepo stuff confused me!

My question is — was solving the edge bleed worth the (assumed) performance tradeoff? There were a couple vendor APIs that seemed to have smarter edge bleed options, but they performed worse. I never got around to actually visually comparing the images, though...

Thanks for all the great comments in your repo, they were quite helpful when trying to figure out how Stack Blur worked!

[LoganDark]

> My question is — was solving the edge bleed worth the (assumed) performance tradeoff?

Absolutely. Edge bleed is a distracting visual artifact! If you take a look at the video in my README, you'll see how bad it is. It's slightly less bad if you implement the sRGB transfer functions properly, but it's still bad.

As for the performance tradeoff - it's probably not as big as you think. However, I can say there is a huge performance tradeoff in using real division, and the only reason I can't use libdivide is the fact that my denominator changes. That's some 30% of the runtime - replacing it with a multiplication (as in libdivide) would probably shave at least 20% off the runtime of my algorithm.

> Thanks for all the great comments in your repo, they were quite helpful when trying to figure out how Stack Blur worked!

You're welcome! I will admit, I mainly wanted to prove that I actually came up with a better version of the algorithm, and that my library was therefore the best :)

[sudara]

> If you take a look at the video in my README, you'll see how bad it is.

Ahh, the video threw me off originally, I think because of the FPS glitches on the full width — but I see it now! Big bands of blue on the left and right edges. I'll have to cook up some examples to reproduce. Also curious what it means (if anything) in the drop shadow context.

> I can say there is a huge performance tradeoff in using real division

Makes sense. It would also throw a wrench in my vector implementations, where the expectation is to perform the same operation efficiently across groups of pixels.

> and that my library was therefore the best :)

Haha, well it was for me! I don't know Rust, but it helped me figure out my first C++ implementations!

[LoganDark]

> Also curious what it means (if anything) in the drop shadow context.

Nothing if the edges of your bitmap (up to the blur's radius) are transparent. :)

[anonymoushn]

It seems like it should still be a win to use libdivide or something like libdivide even if the divisor varies within a row - you get to reuse those divisors for each row!

[LoganDark]

Actually, it's even better since you can use the same set of precomputed dividers for rows and columns. Maybe I'll look into it.