Re: Linear gradients, Transforms and angles...

On Sep 22, 2010, at 13:20 , Brad Kemper wrote:
>> I think many people, if asked, "on a cartesian grid, what is the relationship between a vector along the Y-axis and a vector at 90 degrees?" would say that they are the same,
> 
> Really? I think most would look at you funny and say, "What the heck are you talking about? Speak English, man!" (well, maybe not most; maybe just English speakers would say that). Maybe if you were asking people in a math class or something...
> 
> 

>> and surprise might not be enough if told that the Y axis is at MINUS 90 degrees.  They may need astonishment.
>> 
>> David Singer
>> Multimedia and Software Standards, Apple Inc.
> 
> I've not heard of any astonishment from people setting gradient directions in Adobe products or in your own company's products (Pages, Keynote).



CSS is a language in which you express geometric concepts textually, not wysiwyg.  The idea that you can work in a language expressing geometric concepts without understanding geometry is odd, to say the least.  I could not find a way to ask Photoshop for a gradient at a specified angle (it seems you always click and drag), but the sample preset gradients in the drop-down are actually at 45º -- from top left to bottom right.  These programs are all wysiswyg and the user doesn't have to program in a coordinate system, so the CSS consistency issue does not arise.

I think users want rotations (transforms) and gradients to be consistent -- that two, at 45º, go the same way.  They want to learn one, well-defined, coordinate space, not have to remember that there are two somewhat intuitive, but different, conventions at work depending on what they are working with.

> 

David Singer
Multimedia and Software Standards, Apple Inc.

Received on Wednesday, 22 September 2010 23:37:26 UTC