Re: [PATCH 4/4] user32: Scale the button size with screen resolution.

[Dmitry Timoshkov]

Huw Davies  wrote:
> - checkBoxWidth  = 12 * GetDeviceCaps( hDC, LOGPIXELSX ) / 96 + 1;
> - checkBoxHeight = 12 * GetDeviceCaps( hDC, LOGPIXELSY ) / 96 + 1;

Are you sure that user32 is really supposed to scale the buttons? Could that
be that it's only new comctl32 implementation should do this kind of thing?
Scaling the buttons has the potential of completely distorting the dialog
layout, and I really would like to see some tests for this behaviour (even
a standalone application would be acceptable).

[PATCH 4/4] user32: Scale the button size with screen resolution.

[Huw Davies]

On 22 Aug 2016, at 09:34, Dmitry Timoshkov  wrote:
> Huw Davies  wrote:
> > - checkBoxWidth  = 12 * GetDeviceCaps( hDC, LOGPIXELSX ) / 96 + 1;
> > - checkBoxHeight = 12 * GetDeviceCaps( hDC, LOGPIXELSY ) / 96 + 1;
>
> Are you sure that user32 is really supposed to scale the buttons? Could that
> be that it's only new comctl32 implementation should do this kind of thing?
> Scaling the buttons has the potential of completely distorting the dialog
> layout, and I really would like to see some tests for this behaviour (even
> a standalone application would be acceptable).

Yes, I’m sure.  It’s pretty difficult to write a non-interactive test short of comparing
bits in a bitmap.  Here’s a very simple test I was using to do this visually.  You’ll
want to ensure that the ‘Use Windows XP style DPI scaling’ box remains checked
when you change the resolution, otherwise Windows will do its horrible auto-scaling
thing which will confuse the situation (as well as making everything blurry!).

Huw.

[PATCH 4/4] user32: Scale the button size with screen resolution.

[Dmitry Timoshkov]

Huw Davies  wrote:
> On 22 Aug 2016, at 09:34, Dmitry Timoshkov  wrote:
> > Huw Davies  wrote:
> > > - checkBoxWidth  = 12 * GetDeviceCaps( hDC, LOGPIXELSX ) / 96 + 1;
> > > - checkBoxHeight = 12 * GetDeviceCaps( hDC, LOGPIXELSY ) / 96 + 1;
> >
> > Are you sure that user32 is really supposed to scale the buttons? Could that
> > be that it's only new comctl32 implementation should do this kind of thing?
> > Scaling the buttons has the potential of completely distorting the dialog
> > layout, and I really would like to see some tests for this behaviour (even
> > a standalone application would be acceptable).
>
> Yes, I’m sure.  It’s pretty difficult to write a non-interactive test short of comparing
> bits in a bitmap.  Here’s a very simple test I was using to do this visually.  You’ll
> want to ensure that the ‘Use Windows XP style DPI scaling’ box remains checked
> when you change the resolution, otherwise Windows will do its horrible auto-scaling
> thing which will confuse the situation (as well as making everything blurry!).

Thanks, I tested under XP to eliminate the auto-scaling factor, and it appeears
that you are correct: Windows scales the buttons according to current DPI setting.