[HarfBuzz] "High-DPI, Subpixel Text Positioning, Hinting"

[Behdad Esfahbod]

On 12-11-24 02:52 PM, Jiang Jiang wrote:
> Hi Behdad,
> 
> On Thu, Nov 22, 2012 at 11:13 PM, Behdad Esfahbod <behdad at behdad.org> wrote:
>> [Excuse my cross-lists posting]
>>
>>
>> A while back I wrote a document about the interactions of high-density
>> displays and font rendering options.  I just went ahead and made it public,
>> so, enjoy!
>>
>>   http://goo.gl/yf3M7
> 
> A very good read indeed. I've noticed that on my rMBP certain fonts
> like Arial have terrible spacing in Safari while some other fonts
> don't. It is quite noticeable to trained eyes even when reading your
> article (presented by Google Docs in Arial). So looks like that is a
> caveat from the hybrid method used by Apple.

I walked into an Apple store and checked this.  I completely agree that it
looks really bad.


> Opera 12 on Mac seemed to have the same problem on my rMBP.
> 
> Out of curiosity, which method does Chrome choose to handle high
> resolution displays like rMBP? Is --enable-text-subpixel-positioning
> still in use?

To be honest, I'm not sure what the Mac version is shipping right now.  I
should go figure out though.


> Do you aware of any way to force using sub-pixel positioning with
> Apple's WebKit port?

No.

> Jonathan, can you please comment on the case for Firefox as well? I
> noticed that the latest nightlies have turn on the high DPI support.

Robert O'Callahan left this comment on the document:

"You might want to mention what Firefox does --- which is "Remove Linearity
Requirement". But if the underlying platform rasterizer doesn't use hinting or
subpixel positioning, we respect that."

-- 
behdad
http://behdad.org/