Changing the Zoom correction factor has no effect in the editing window

[Dale Walton]

Inkscape 0.91 r13725
Windows 7 Professional 64 bit, SP1 (International English)
4 GB RAM
Intel Core 2 Quad CPU

Changing the Zoom correction factor in the Preference popup has no affect in the edit window:

I don't know if this was already an issue, as I did not try to adjust this after installing this version, until now.

I just installed a new LG monitor & driver, and changed my windows magnification in NVDIA from 100% to 125%. Then, having more space on the edit screen, I decided to set the image size to match actual size.

By setting a rectangle to the mm dimensions of an A4 and then scaling using transformations it until it matched an actual piece on A4 paper, I determined that I needed a 114% scale factor.

Applying this in the Preferences dialog showed the correct scale on the dialogue's ruler and recorded the value into the preferences file, but had no affect at all on the display size in the actual program edit/display window.

[su_v (suv-lp)]

The current implementation of the zoom correction factor does work, but likely not as you expect it to: it is simply applied as multiplication factor to the available preset zoom commands 1:1, 1:2, 2:1. [1] It does not change or scale or otherwise affect the resolution of the canvas in any way.

This earlier report tracks improvements / refactoring requests for the current implementation:
* Bug #1081956 “Zoom Correction Factor and Zoom Info improvements”
  https://bugs.launchpad.net/inkscape/+bug/1081956

Proposing to link as duplicate to bug #1482877.

[1] related source code in Inkscape 0.91:
http://bazaar.launchpad.net/~inkscape.dev/inkscape/RELEASE_0_91_BRANCH/view/13725/src/verbs.cpp#L1784
http://bazaar.launchpad.net/~inkscape.dev/inkscape/RELEASE_0_91_BRANCH/view/13725/src/verbs.cpp#L1826

[Dale Walton (dale-walton)]

Dear Inkscape debuggers et. al.,

RE: Your statement:
The current implementation of the zoom correction factor does work, but
likely not as you expect it to: it is simply applied as multiplication
factor to the available preset zoom commands 1:1, 1:2, 2:1. [1] It does
not change or scale or otherwise affect the resolution of the canvas in
any way.

This earlier report tracks improvements / refactoring requests for the
current implementation:
* Bug #1081956 “Zoom Correction Factor and Zoom Info improvements”
=============
Sorry, this is not the case for me.

When I go to Zoom icon then select 1:1 the zoom in the right-hand corner *says
100%* and the screen is not to scale, even though this preference is set to
114% . In other words, I do not see any affect of setting this preference
outside of the preference popup.

Perhaps this feature has been completely deactivated due to the justifiable
complaints that it works incorrectly.
If it has been deactivated, then please take it out of (or deactivate it
in) preferences as well until it is fixed.

I believe this preference should best be intended as a screen correction
factor, and I would interpret the box in the lower right of the edit screen
to refer to screen magnification, where 100% should be derived from this
correction factor (ie when showing 100%, WYSIWYG) and not directly related
to internal pixels.

I don't see why you need to correct major amounts of code, unless mm
currently doesn't mean mm when printing either or in files opened in other
apps.

 -- All you need to do (besides setting the preset Zooms correctly) is to
*display* the zoom level in the lower right corner *as corrected* and leave
it alone internally. i.e. display, instead, the value of a new variable
that is the current variable divided by the preference value.

On Sun, Aug 9, 2015 at 3:02 AM, ~suv <email address hidden> wrote:

> The current implementation of the zoom correction factor does work, but
> likely not as you expect it to: it is simply applied as multiplication
> factor to the available preset zoom commands 1:1, 1:2, 2:1. [1] It does
> not change or scale or otherwise affect the resolution of the canvas in
> any way.
>
> This earlier report tracks improvements / refactoring requests for the
> current implementation:
> * Bug #1081956 “Zoom Correction Factor and Zoom Info improvements”
> https://bugs.launchpad.net/inkscape/+bug/1081956
>
> Proposing to link as duplicate to bug #1482877.
>
> [1] related source code in Inkscape 0.91:
>
> http://bazaar.launchpad.net/~inkscape.dev/inkscape/RELEASE_0_91_BRANCH/view/13725/src/verbs.cpp#L1784
>
> http://bazaar.launchpad.net/~inkscape.dev/inkscape/RELEASE_0_91_BRANCH/view/13725/src/verbs.cpp#L1826
>
> ** Tags added: ui zoom
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1482877
>
> Title:
> Changing the Zoom correction factor has no effect in the editing
> window
>
> Status in Inkscape:
> New
>
> Bug description:
> Inkscape 0.91 r13725
> Windows 7 Professional 64 bit, SP1 (International English)
> 4 GB RAM
> Intel Core 2 Quad CPU
>
> Changing the Zoom correction facto...

[su_v (suv-lp)]

Sorry - my mistake (I should have tested in detail with current stable release 0.91 and trunk before writing my earlier comment).

AFAICT this commit "broke" (or at least changed) the original implementation in Inkscape 0.91 and current trunk (no reasons given, nor a bug report linked):
Revision 13264: Only apply the offset zoom when the document units match the zoom units
https://bazaar.launchpad.net/~inkscape.dev/inkscape/trunk/revision/13264

Apparently now the units with which the ruler (to help to adjust the zoom correction factor) is displayed in the preferences needs to match the 'document units' (Inkscape 0.91) or 'display units' (Inkscape 0.91+devel), otherwise the zoom correction factor is not applied (even though it is just a multiplication factor for the zoom level presets).

Confirming as regression in Inkscape 0.91 for now (needs further investigation into the reasons of commit r3264).

[su_v (suv-lp)]

~suv (suv-lp) wrote:
> Apparently now the units with which the ruler (to help to adjust the
> zoom correction factor) is displayed in the preferences needs to
> match the 'document units' (Inkscape 0.91) or 'display units'
> (Inkscape 0.91+devel), (…)

To clarify: the 'document units' - called 'Default units' in Inkscape 0.91, 'Display units' in Inkscape 0.91+devel - are defined per document in 'File > Document Properties > Page'.

Currently, after r13264, the (global) zoom correction factor only works in documents which use the same default units as used for the ruler display in the preferences pane.

[Dale Walton (dale-walton)]

Now I am really confused why this needs to be so complicated, or why *units*
are even involved, if this should be a display correction.
I am not sure what the Inkscape view of the preference and its purpose is...

In any case, I tried setting the document property units to mm to match mm
in the Preferences / Zoom correction factor units and the result is as you
state, the preset 1:1 now goes to the preference value.

On Sun, Aug 9, 2015 at 9:54 PM, ~suv <email address hidden> wrote:

> ~suv (suv-lp) wrote:
> > Apparently now the units with which the ruler (to help to adjust the
> > zoom correction factor) is displayed in the preferences needs to
> > match the 'document units' (Inkscape 0.91) or 'display units'
> > (Inkscape 0.91+devel), (…)
>
> To clarify: the 'document units' - called 'Default units' in Inkscape
> 0.91, 'Display units' in Inkscape 0.91+devel - are defined per document
> in 'File > Document Properties > Page'.
>
> Currently, after r13264, the (global) zoom correction factor only works
> in documents which use the same default units as used for the ruler
> display in the preferences pane.
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1482877
>
> Title:
> Changing the Zoom correction factor has no effect in the editing
> window
>
> Status in Inkscape:
> Confirmed
>
> Bug description:
> Inkscape 0.91 r13725
> Windows 7 Professional 64 bit, SP1 (International English)
> 4 GB RAM
> Intel Core 2 Quad CPU
>
> Changing the Zoom correction factor in the Preference popup has no
> affect in the edit window:
>
> I don't know if this was already an issue, as I did not try to adjust
> this after installing this version, until now.
>
> I just installed a new LG monitor & driver, and changed my windows
> magnification in NVDIA from 100% to 125%. Then, having more space on
> the edit screen, I decided to set the image size to match actual size.
>
> By setting a rectangle to the mm dimensions of an A4 and then scaling
> using transformations it until it matched an actual piece on A4 paper,
> I determined that I needed a 114% scale factor.
>
> Applying this in the Preferences dialog showed the correct scale on
> the dialogue's ruler and recorded the value into the preferences file,
> but had no affect at all on the display size in the actual program
> edit/display window.
>
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/inkscape/+bug/1482877/+subscriptions
>

[Jonathan Hofinger (jhofinger)]

Hi, this issue has been fixed in master: https://gitlab.com/inkscape/inkscape/-/issues/1048

Closed by: https://gitlab.com/jhofinger