Re: Making pt a non-physical unit

On Jan 14, 2010, at 1:59 PM, David Singer <singer@apple.com> wrote:

>
> On Jan 14, 2010, at 12:12 , Brad Kemper wrote:
>
>>
>>
>> On Jan 14, 2010, at 11:58 AM, David Singer <singer@apple.com> wrote:
>>
>>>> I don't like that part. If I know that a scoreboard at the ball  
>>>> park is 800 pixels wide, with pixels the size of lightbulbs or  
>>>> whatever, I should be able to use that information to create  
>>>> borders that are one or two or three device pixels in width. It  
>>>> shares the same characteristics as other screen media.
>>>
>>> There is a huge assumption here of a tie between the designer and  
>>> the output device, which is very rare.
>>
>> For things like scoreboards or billboards, I disagree. Someone who  
>> wishes to advertise on a billboard needs to tailed their content  
>> for that output. Baseball scoreboards show content that was  
>> designed to be shown there. I've never seen anything that size that  
>> was there to just display any content at all from the Web.
>
>
> OK, but if you know the output device you're working towards, then  
> you also know that it's defined, for example, 1 CSS pixel as being 6  
> true inches.  For the 'closet' case where it's a closed system,  
> people can work it out.  Clear specs are needed for arbitrary  
> interoperability.

I also want them to be clear:

For print media where the print driver or printer engine understands  
physical dimensions such as inches (which should be most printers that  
matter), define pixels as being 1/96 inches. For all others, define  
inches as being 96 device pixels. Then apply zooming or scaling.

I don't think it matters if 1px on the Jumbotron is twice the size as  
it might be on a billboard of the same size. I'm not using either one  
to browse the Web; instead I'm paying huge sums to advertise on them,  
and will make sure that my money is well spent, by tweaking my design  
for the output device. Or if I want a more widely applicable design  
for varying resolutions (with some minimum rez probably), I'll use  
different units (percentages, inches, ems,, etc.) to acheive my goals.