What happens when enabling Hi-DPI scaling?

[Mark Waddingham]

On 2015-10-26 10:52, Tiemo Hollmann TB wrote:
> I don't have a Hi-DPI monitor and didn't found anything in the forum 
> about
> it, so I am unsure what happens with my stack if I would enable this
> setting? What exactly happens when it says "if enabled, the stack will 
> be
> scaled to fit"? A Hi-Res monitor has a higher pixel density, but my 
> program
> windows and objects have fixed sizes in pixel. My understanding is, if 
> I
> don't enable this setting, my stacks will be displayed smaller on a 
> Hi-DPI
> monitor? Correct? And enabling this setting, are they scaled to the 
> "same
> appearance", as on a standard monitor? Or what happens? If yes, 
> probably
> images get blurred, when being scaled, so you shouldn't enable this 
> option
> when you use images, correct?

Hi-DPI scaling makes it so that if the systems 'pixel scale' (the 
mapping from virtual pixels to physical pixels) is not 1-1, the engine 
will appropriately render things to use the 'extra fidelity'.

A stack which is 400x400 in LiveCode, will still appear to be 400x400 on 
a Retina display, say, except that it will actually be rendering at 
800x800 - making things crisper.

Depending on the version of Windows you are targetting, you can 
experiment with HiDPI by adjusting the 'text scaling' option in the 
system preferences.

> Why is the Hi-DPI support for Windows a chooseable option and for OS X 
> it is
> standard since 6.7.6 (6.7.7)? Do images don't get blurred, when the 
> stack is
> resized on OS X? Why can't I disable this option on OS X?

Windows does not allow the runtime configuration of Hi-DPI 'pixel 
scaling' - it has to be specified as part of the Applications 'manifest' 
which is integrated at standalone build time.

Mac, however, does allow toggleing configuration of Hi-DPI 'pixel 
scaling' at runtime - see the 'usePixelScaling' option.

By default, the Mac engine will use as many pixels as it can - so if you 
have a retina display, you will get pixel scaling (but you can turn it 
off - set the usePixelScaling to false).

On Windows, by default pixel scaling is turned off, but you can choose 
to use it for your app by turning it on in the standalone builder.

Warmest Regards,

Mark.

-- 
Mark Waddingham ~ mark at livecode.com ~ http://www.livecode.com/
LiveCode: Everyone can create apps