Re: [css3-background] vastly different takes on "blur"

On Jun 22, 2010, at 1:42 PM, Brad Kemper wrote:

> On Jun 22, 2010, at 12:07 PM, "Tab Atkins Jr." <jackalmage@gmail.com> wrote:
> 
>> What we're all saying is that, when we're thinking about how much to
>> blur, what we mentally care about is how much the blur extends out
>> from the normal shadow.  The amount that the blur extends into the
>> normal shadow isn't relevant to our decision on how much to blur.
> 
> That's the part that still seems indefensible. Whatever direction it extends, it is part of the blur for which the author provided a distance measure. How can that possibly be irrelevant to the blur value provided? If all you cared about was how far it how far it extended (and I know ghats nit the case), you wouldn't need blur. So when you say you are visually picking an attractive blur in conjunction with that decision, then you are just visually and concurrently picking a blurriness that can be represented by a number, regardless of which way it extends.

Think of the blur amount as the furthest distance that a pixel gets "smeared"  in any one direction (and, yes, under the hood it really is a radius, used as input to a gaussian blur filter). Or, another way to put it is that the blur amount gives the furthest distance over which any one pixel has an influence. I think this is quite understandable by designers, and, as we can tell from PhotoShop, something that is already familiar to many people.

Now can we just move on?

Simon

Received on Tuesday, 22 June 2010 20:47:40 UTC