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Re: Perlin and simplex noise

From: David Sheets <kosmo.zb@gmail.com>
Date: Fri, 31 Aug 2012 14:00:48 -0700
Message-ID: <CAAWM5TxvhmqqRXg8yJQT6YWM+TJeXR+ntD1n9CxOv9P=gbk-2Q@mail.gmail.com>
To: "Tab Atkins Jr." <jackalmage@gmail.com>
Cc: Erik Dahlstrom <ed@opera.com>, www-svg@w3.org, "public-fx@w3.org" <public-fx@w3.org>
On Fri, Aug 31, 2012 at 1:53 PM, Tab Atkins Jr. <jackalmage@gmail.com> wrote:
> On Fri, Aug 31, 2012 at 1:49 PM, David Sheets <kosmo.zb@gmail.com> wrote:
>> On Fri, Aug 31, 2012 at 10:05 AM, Tab Atkins Jr. <jackalmage@gmail.com> wrote:
>>> (While we're at it, though, we should pay attention to how it would be
>>> possible to do declarative randomness in properties.  Marrying a
>>> stateful RNG with a nominally stateless language is hard. :/ )
>>
>> Procedural noise can be seeded from time alone. I believe that CSS
>> transitions should be able to provide custom shaders with a fractional
>> completeness value, no? Is there a means in New CSS to create
>> unbounded animation?
>
> I may have been unclear about what the issue is.
>
> If using randomness to, say, set the background-color of an element,
> you usually will want different elements to have different random
> values.

Procedural noise is not random.

> However, you also want these values to be stable across common types
> of changes, like temporarily setting the background-color to a
> non-random value on hover, then returning to the random color
> afterwards.

I believe that CSS custom shader parameters handle this case.
<https://dvcs.w3.org/hg/FXTF/raw-file/tip/custom/index.html#other-uniform-variables-the-css-shaders->

> Handling this intelligently and with a minimum of fuss seems
> non-trivial, though I do have some ideas of how to possibly do it.

What part of the present design is insufficient for your use case?

David

> ~TJ
Received on Friday, 31 August 2012 21:02:08 GMT

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