[Development] [HiDPI] Rethinking the scaling algorithm

[Niccolò Belli]

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On martedì 8 novembre 2016 23:34:48 CET, Allan Sandfeld Jensen wrote:
> On Tuesday 08 November 2016, Niccolò Belli wrote:
>> 1) Always round down. With your current formula a 145ppi 
>> screen gets scaled
>> by a 2x factor, while every other toolkit (GTK3 for example[3]) starts
>> scaling at 192ppi. This is also what people expect and it would return the
>> correct 2x scaling factor for my laptop. So the formula should be
>> scaling_factor=qRoundDown(yourDpi/96)
>> 
> We have a two factor scaling system. We also scale by DPI. 144/2 == 72 for 
> instance, which happens to be the standard on Macs. Therefore 
> 144DPI become a 
> normal 2x scaling of standard 72 Mac DPI. 
>
> And having 2x with smaller text, is a lot better than 1x with 
> large text on a 
> 27" 4K desktop screen.
>
> `Allan
>
>