set font size with ctrl-mouse wheel?

set font size with ctrl-mouse wheel?

[Neal Becker]

It is becoming fairly standard to use ctrl+mouse-wheel to increase/decrease 
font size.  It'd be great if emacs could do this.

RE: set font size with ctrl-mouse wheel?

[Drew Adams]

> It is becoming fairly standard to use ctrl+mouse-wheel to 
> increase/decrease 
> font size.  It'd be great if emacs could do this.

It's been discussed before. I don't remember the threads, but you can find them
at http://lists.gnu.org/archive/html/emacs-devel/.

My recollection is that this idea was rejected because (1) the wheel is treated
differently on different platforms, and (2) Control+wheel was not considered to
be standar, but my memory of this might be wrong.


FWIW, you can get that behavior with library zoom-frm.el:

http://www.emacswiki.org/emacs/SetFonts#ChangingFontSize

http://www.emacswiki.org/emacs/zoom-frm.el

Re: set font size with ctrl-mouse wheel?

[Peter Brett]

Neal Becker <ndbecker2@gmail.com> writes:

> It is becoming fairly standard to use ctrl+mouse-wheel to increase/decrease 
> font size.

It is?  A quick straw poll of editors and other dev tools:

gvim             n
gedit            n
nedit            n
Bluefish         n
cssed                  y
geany                  y
quanta           n
SciTE                  y
Eclipse          n
xml-copy-editor        y
Kmail            n
Kile             n   
GNU TeXMACS      n

...indicates that by "fairly standard" you mean "some applications do it".

> It'd be great if emacs could do this.

It can.  This should get you started. [*]

(defvar text-height-scale-factor 0.2)

(defun scale-text-height (s)
  "Scale the current text height"
  (set-face-attribute 'default nil :height
    (truncate (* s (face-attribute 'default :height)))))
(defun reduce-text-height ()
  "Reduce the text height"
  (interactive)
  (scale-text-height (- 1.0 text-height-scale-factor)))
(defun increase-text-height ()
  "Increase the text height"
  (interactive)
  (scale-text-height (+ 1.0 text-height-scale-factor)))

(global-set-key [C-mouse-4] 'reduce-text-height)
(global-set-key [C-mouse-5] 'increase-text-height)


Best wishes,

                                          Peter

[*] Someone will be along shortly to explain how I could have achieved
    this in less than half as much ELisp.

-- 
Peter Brett <peter@peter-b.co.uk>
Remote Sensing Research Group
Surrey Space Centre

Re: set font size with ctrl-mouse wheel?

[Leo]

On 2009-07-30 12:53 +0100, Neal Becker wrote:
> It is becoming fairly standard to use ctrl+mouse-wheel to increase/decrease 
> font size.  It'd be great if emacs could do this.

I believe this is not the case. Using mouse wheel to change font size is
almost useless, especially for emacs.

-- 
Leo's Emacs uptime: 50 days, 0 hours, 45 minutes, 59 seconds

RE: set font size with ctrl-mouse wheel?

[Drew Adams]

> > It'd be great if emacs could do this.
> 
> I believe this is not the case. Using mouse wheel to change 
> font size is almost useless, especially for emacs.

Why is it "almost useless"? I use it all the time. Very handy.

Yes, C-wheel might not be "standard", but it is pretty common - for MS Windows
users, at least (and that's a lot of users). It works in many apps on Windows,
from browsers to mail clients to, yes, editors.

It's simple to use, and it doesn't really conflict with any existing Emacs key
bindings, AFAIK. Yes, mwheel-scroll uses C-wheel, but it also uses just plain
wheel - no real need for it to also claim C-wheel, AFAICT.

You might not care to use C-wheel to zoom, in Emacs or elsewhere, but what
reason do you have to say that it "is almost useless, especially for emacs"?

Re: set font size with ctrl-mouse wheel?

[Leo]

On 2009-07-30 15:42 +0100, Drew Adams wrote:
>> > It'd be great if emacs could do this.
>> 
>> I believe this is not the case. Using mouse wheel to change 
>> font size is almost useless, especially for emacs.
>
> Why is it "almost useless"? I use it all the time. Very handy.
> 
> Yes, C-wheel might not be "standard", but it is pretty common - for MS
> Windows users, at least (and that's a lot of users). It works in many
> apps on Windows, from browsers to mail clients to, yes, editors.

C-=, C-+ and C-0 are more standard way of changing font size and Emacs
has provided similar key bindings for them. In my view, this is
sufficient.

> It's simple to use, and it doesn't really conflict with any existing
> Emacs key bindings, AFAIK. Yes, mwheel-scroll uses C-wheel, but it
> also uses just plain wheel - no real need for it to also claim
> C-wheel, AFAICT.

> You might not care to use C-wheel to zoom, in Emacs or elsewhere, but
> what reason do you have to say that it "is almost useless, especially
> for emacs"?

Like I said, Emacs already has something for it. There is little use to
put in some extra non-standard, uncommon and clumsy feature.

-- 
Leo's Emacs uptime: 50 days, 1 hour, 32 minutes, 13 seconds

RE: set font size with ctrl-mouse wheel?

[Drew Adams]

> >> > It'd be great if emacs could do this.
> >> 
> >> I believe this is not the case. Using mouse wheel to change 
> >> font size is almost useless, especially for emacs.
> >
> > Why is it "almost useless"? I use it all the time. Very handy.
> > 
> > Yes, C-wheel might not be "standard", but it is pretty 
> > common - for MS Windows users, at least (and that's a lot
> > of users). It works in many apps on Windows, from browsers
> > to mail clients to, yes, editors.
> 
> C-=, C-+ and C-0 are more standard way of changing font size and Emacs
> has provided similar key bindings for them. In my view, this is
> sufficient.

OK, I see. By "almost useless" you meant only that you already have a different
way to do it, and one way is sufficient.

A keyboard is sufficient perhaps - why have a mouse?

> > It's simple to use, and it doesn't really conflict with any existing
> > Emacs key bindings, AFAIK. Yes, mwheel-scroll uses C-wheel, but it
> > also uses just plain wheel - no real need for it to also claim
> > C-wheel, AFAICT.
> 
> > You might not care to use C-wheel to zoom, in Emacs or 
> > elsewhere, but what reason do you have to say that it
> > "is almost useless, especially for emacs"?
> 
> Like I said, Emacs already has something for it. There is 
> little use to put in some extra non-standard, uncommon and
> clumsy feature.

1. Just because Emacs has one way to do something is not a reason it shouldn't
also have other ways to do it. If you applied that logic, you could remove
everything except `M-:' or `C-x C-e'.

2. It's not clear at all that `C-=' etc. are more standard than C-wheel. But
even if they were, see point #1.

3. There is nothing uncommon or clumsy about C-wheel. (a) It is very common. (b)
You haven't shown that it is "clumsy".

Of course, if you take as a given that all use of a mouse is "clumsy", then sure
(you've convinced yourself). By that argument, Emacs should remove all mouse and
menu and tool-bar support - too clumsy. But many (most?) users of computers
these days do use a mouse at least some of the time - that's hardly "uncommon".

At least it's clear now what your arguments are and what you meant by "almost
useless".

Re: set font size with ctrl-mouse wheel?

[Leo]

On 2009-07-30 20:18 +0100, Drew Adams wrote:
>> Like I said, Emacs already has something for it. There is 
>> little use to put in some extra non-standard, uncommon and
>> clumsy feature.
>
> 1. Just because Emacs has one way to do something is not a reason it shouldn't
> also have other ways to do it. If you applied that logic, you could remove
> everything except `M-:' or `C-x C-e'.

Firstly, just because Microsoft has something standard in their
applications, it should be added to Emacs? There might be a lot of
windows users but only a very small proportion use Emacs.

Secondly, if you stretch any argument to an extreme extent, it will
fail. Try your arguments and you will see none of them holds water.

The point is: C-x C-= is comparable to C-Mouse4/5 and it gives the user
a more precise control.

> 2. It's not clear at all that `C-=' etc. are more standard than
>C-wheel. But
> even if they were, see point #1.
> 3. There is nothing uncommon or clumsy about C-wheel. (a) It is very
> common. (b) You haven't shown that it is "clumsy".

Point 2 and 3 just show how little you have spent outside Microsoft
products.

-- 
Leo's Emacs uptime: 50 days, 6 hours, 39 minutes, 4 seconds

Re: set font size with ctrl-mouse wheel?

[Stefan Monnier]

> It is becoming fairly standard to use ctrl+mouse-wheel to increase/decrease 
> font size.  It'd be great if emacs could do this.

I'm not sure how standard it is, and how important it is: Emacs hasn't
had zooming at all for many years, and few people asked for it.

OTOH C-wheel-{up/down} does not currently have a very important binding
(it just changes the increment used for scrolling), OTOH this binding is
also used in Firefox and presumably a few other applications.

So, I'm not opposed to such a change, but I think we should first wait
to see if it really becomes standard.


        Stefan

RE: set font size with ctrl-mouse wheel?

[Drew Adams]

> > 1. Just because Emacs has one way to do something is not a 
> > reason it shouldn't also have other ways to do it. If you
> > applied that logic, you could remove everything except
> > `M-:' or `C-x C-e'.
> 
> Firstly, just because Microsoft has something standard in their
> applications, it should be added to Emacs?

Did someone say that? Does that follow from #1?

It was _your_ argument that because Emacs already has one way (C-=) to zoom
there is no need for another way (C-wheel). That argument has no relation to
Microsoft.

> There might be a lot of
> windows users but only a very small proportion use Emacs.

So what? How is that relevant? And do you want to keep it that way?

Is it because Microsoft apps often use C-wheel to zoom that that is a bad thing
to do?

Is it because that UI practice is too common or because it's too uncommon that
it's a bad idea? Please decide.

> The point is: C-x C-= is comparable to C-Mouse4/5 and it 
> gives the user a more precise control.

Nonsense. For one thing, one uses the keyboard; the other uses the mouse. For
another thing, mouse4/5 work differently in Emacs on different platforms. For a
third thing, mouse4/5 sometimes control - you guessed it - the wheel (perhaps
they shouldn't, but they do). For a fourth thing, there is no less control using
a wheel than a mouse button.

> > 2. It's not clear at all that `C-=' etc. are more standard than
> >    C-wheel. But even if they were, see point #1.
> > 3. There is nothing uncommon or clumsy about C-wheel. (a) It is very
> >    common. (b) You haven't shown that it is "clumsy".
> 
> Point 2 and 3 just show how little you have spent outside Microsoft
> products.

Uh, surely we need not descend to comparing how far we can each piss, Leo? I'll
bet you weren't even born when I started programming and using non-Microsoft
software. Your father might not even have been born yet! ;-) Unix wasn't born
yet either, for that matter. But such "arguments" are irrelevant, aren't they?
What counts are one's reasons and reasoning.

When logical argument fails, you resort to ad hominem and the too-easy
dread-and-hatred of the Microsoft Boogeyman. That's too bad, but thanks for
making clear the substance behind your "arguments".

Re: set font size with ctrl-mouse wheel?

[Chad Brown]

Without getting into the ``is too/is not'' fight, I also find this  
binding far more useful than I had originally expected (and not on  
Windows, if that matters), and would welcome, say, an included mode to  
turn it on via something simple like custom or (load ...).

One thing to keep in mind:  under macosx, there is a system-wide `zoom  
the display' feature bound to ctrl-wheel (it might not be enabled by  
default; I forget).

*Chad

Re: set font size with ctrl-mouse wheel?

[CHENG Gao]

*On Thu, 30 Jul 2009 15:31:57 -0700
* Also sprach Chad Brown <yandros@MIT.EDU>:

> One thing to keep in mind:  under macosx, there is a system-wide `zoom
> the display' feature bound to ctrl-wheel (it might not be enabled by
> default; I forget).
>
> *Chad

Seems it's enabled by default, at least for my 10.5.7.

Re: set font size with ctrl-mouse wheel?

[Jan Djärv]

Drew Adams skrev:
>>> 1. Just because Emacs has one way to do something is not a 
>>> reason it shouldn't also have other ways to do it. If you
>>> applied that logic, you could remove everything except
>>> `M-:' or `C-x C-e'.
>> Firstly, just because Microsoft has something standard in their
>> applications, it should be added to Emacs?
> 
> Did someone say that? Does that follow from #1?
> 

You did:

> Yes, C-wheel might not be "standard", but it is pretty common - for MS Windows
> users, at least (and that's a lot of users). It works in many apps on Windows,
> from browsers to mail clients to, yes, editors.

C-mouse-wheel does something already on OS X (zoom desktop), so it is a 
conflict right there.

	Jan D.

RE: set font size with ctrl-mouse wheel?

[Neal Becker]

Drew Adams wrote:

>> It is becoming fairly standard to use ctrl+mouse-wheel to
>> increase/decrease
>> font size.  It'd be great if emacs could do this.
> 
> It's been discussed before. I don't remember the threads, but you can find
> them at http://lists.gnu.org/archive/html/emacs-devel/.
> 
> My recollection is that this idea was rejected because (1) the wheel is
> treated differently on different platforms, and (2) Control+wheel was not
> considered to be standar, but my memory of this might be wrong.
> 
> 
> FWIW, you can get that behavior with library zoom-frm.el:
> 
> http://www.emacswiki.org/emacs/SetFonts#ChangingFontSize
> 
> http://www.emacswiki.org/emacs/zoom-frm.el

Thanks!  I can confirm zoom-frm works.  But, it also requires:
frame-fns.el
frame-cmds.el

I favor adding (at least the abililty to easily bind, if not the default 
binding) of ctrl-mouse-wheel as standard in emacs - but I think requiring 
all 3 of these files to do it is a bit heavy-weight.  Perhaps there is a 
simpler approach?

Re: set font size with ctrl-mouse wheel?

[Tassilo Horn]

Neal Becker <ndbecker2@gmail.com> writes:

Hi Neal,

>> http://www.emacswiki.org/emacs/zoom-frm.el
>
> Thanks!  I can confirm zoom-frm works.  But, it also requires:
> frame-fns.el
> frame-cmds.el
>
> I favor adding (at least the abililty to easily bind, if not the
> default binding) of ctrl-mouse-wheel as standard in emacs

There is an easy way (at least in emacs 23.1):

--8<---------------cut here---------------start------------->8---
(global-set-key (kbd "<C-mouse-5>") 'text-scale-increase)
(global-set-key (kbd "<C-mouse-4>") 'text-scale-decrease)
--8<---------------cut here---------------end--------------->8---

Bye,
Tassilo

RE: set font size with ctrl-mouse wheel?

[Drew Adams]

> >>> 1. Just because Emacs has one way to do something is not a 
> >>> reason it shouldn't also have other ways to do it. If you
> >>> applied that logic, you could remove everything except
> >>> `M-:' or `C-x C-e'.
> >>
> >> Firstly, just because Microsoft has something standard in their
> >> applications, it should be added to Emacs?
> > 
> > Did someone say that? Does that follow from #1?
> 
> You did:

No, I most definitely did not. You guys really need to bone up on English or
logic.

I have _never_ argued that _because_ Microsoft (or Apple or any other producer
of software, commercial or otherwise) does something Emacs should also do the
same thing. Never.

I absolutely reject such an argument, just as I reject the argument that because
they do something Emacs should _not_ do it. Or because they do not do something
Emacs should do it. You might reason that way, but I do not.

You are free to quote what I say back at me, but do not misquote me or lie about
what I say.

> > Yes, C-wheel might not be "standard", but it is pretty 
> > common - for MS Windows users, at least (and that's a lot
> > of users). It works in many apps on Windows,
> > from browsers to mail clients to, yes, editors.

That is not an argument that this is good to do _because_ Microsoft does it.
That is a statement that lots of people are currently using it. Not at all the
same thing.

And I specifically said "at least", suggesting that this is only one data point.
I didn't know about others, such as Apple, but I left open the possibility that
they exist.

I hold no brief for Microsoft. I was simply conveying the fact that this is not
an uncommon user interface.

Is your hatred of Microsoft perhaps blinding you to ordinary logic? I'm no
special fan of Microsoft, myself, but I distinguish (a) the company from the
technical aspects of its product user-interfaces, and (b) the company from its
users. And no, I also do not defend all Microsoft user interfaces or all
Microsoft users - far from it.

But I am able to see past the logo, to judge for myself whether some UI aspect
is good or bad. Being blinded (in either direction) by a label is a terrible
handicap, and it gives the label more power than it deserves.

RE: set font size with ctrl-mouse wheel?

[Drew Adams]

> Thanks!  I can confirm zoom-frm works.  But, it also requires:
> frame-fns.el
> frame-cmds.el
> 
> I favor adding (at least the abililty to easily bind, if not 
> the default binding) of ctrl-mouse-wheel as standard in emacs

So do I.

> but I think requiring all 3 of these files to do it is a bit
> heavy-weight.

Yes, of course. But those libraries do more than that.

> Perhaps there is a simpler approach?

Just extract the part of those libraries that does only what you want.

If all you want is text scaling (available starting with Emacs 23), then this is
all you need (extracted from the definitions in zoom-frm.el):

(defun zoom-in ()
 (interactive)
 (with-current-buffer
     (if (string-match "mouse" (format "%S" (event-basic-type
                                             last-command-event)))
         (window-buffer (posn-window (event-start last-command-event)))
       (current-buffer))
   (text-scale-increase 1)))

(defun zoom-out ()
 (interactive)
 (with-current-buffer
     (if (string-match "mouse" (format "%S" (event-basic-type
                                             last-command-event)))
         (window-buffer (posn-window (event-start last-command-event)))
       (current-buffer))
   (text-scale-decrease 1)))

(global-set-key (vector (list 'control mouse-wheel-down-event)) 'zoom-in)
(global-set-key (vector (list 'control mouse-wheel-up-event)) 'zoom-out)

RE: set font size with ctrl-mouse wheel?

[Drew Adams]

> There is an easy way (at least in emacs 23.1):
> (global-set-key (kbd "<C-mouse-5>") 'text-scale-increase)
> (global-set-key (kbd "<C-mouse-4>") 'text-scale-decrease)

That doesn't work in Windows. But this works in Windows:

(global-set-key (kbd "<C-wheel-up>") 'text-scale-increase)
(global-set-key (kbd "<C-wheel-down>") 'text-scale-decrease)