Colored font rendering problem in terminal.

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Pierre

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Oct 22, 2011, 1:49:53 PM10/22/11
to iSSH/iX11
Hi Dean. Love iSSH. Use it all the time.

Since iOS 5 was released (or iSSH 5?) I noticed a problem, probably
the same one identified by the first point of user yieldthought above.
By experimenting I discovered that the terminal doesn't render
properly
the spacing between characters when there are CSI control sequences
that changes the color of the font. For instance, a "ls" command in
a unix shell with the coloring options turned on will result in a
table
of filenames that's badly aligned, if the file list contains all sorts
of
entries (files, directories, symlinks) colored differently. Another
example
is when using a text editor with syntax highlighting. In VIM, if I
turn on or
off syntax highlighting I can see the horizontal alignment of all
characters
in the terminal change considerably, back and forth.

The misalignment can result in the cursor being shown at a completely
different character position than what it actually thinks it is at.

This happens with all fonts you support EXCEPT 'Classic' (which is
darn
ugly for shell use, IMO).

Pierre

Ezra

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Oct 28, 2011, 4:41:29 AM10/28/11
to iSSH/iX11
Just wanted to mention that along with a weird keyboard issue with
extra control/meta characters showing up when using the control keys
-- I have this strange rendering issue as well. It makes issh
basically unusable for its intended purpose -- It really does seem
like an ios 5 issue/difference in font rendering. Adjusting the
columns does not make it go away, it just makes the rendering offset
less relative to the size of a character...

Michael Martin

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Oct 29, 2011, 10:37:40 AM10/29/11
to is...@googlegroups.com

I noticed it too in my colorized ls, though in my case I do not use vi/vim and the like so it is not a big deal for me. iPhone 4, iOS 5.0, iSSH 5.07.


==================================================================
Michael Martin
ArsAstr...@gmail.com
==================================================================

Dean Beeler

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Nov 4, 2011, 3:32:33 AM11/4/11
to iSSH/iX11
The effect isn't consistent across characters across fonts which is
why I didn't notice it at first. Midnight Commander looks right
(mostly) with Courier and Inconsolata but is way off with DejaVu and
ProFont.

Searching to see if I'm not the only one affected I found this:

http://stackoverflow.com/questions/7980812/objective-c-ios5-font-rendering-has-changed

Trying to figure out a work-around. So far I have something that
works but the screen drawing is much, much slower.

Dean

On Oct 29, 7:37 am, Michael Martin <arsastronaut...@gmail.com> wrote:
> I noticed it too in my colorized ls, though in my case I do not use vi/vim and the like so it is not a big deal for me. iPhone 4, iOS 5.0, iSSH 5.07.
>
> ==================================================================
>                            Michael Martin
>                       ArsAstronaut...@gmail.com
> ==================================================================

Maksym Parkachov

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Nov 9, 2011, 4:59:35 AM11/9/11
to iSSH/iX11
Hi Dean,

> http://stackoverflow.com/questions/7980812/objective-c-ios5-font-rend...
>
> Trying to figure out a work-around.  So far I have something that
> works but the screen drawing is much, much slower.

just wanted to ask if you have any update on this. I understand
it will not make it in .10 release, or ?

Regards,
Maksym.

Dean Beeler

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Nov 9, 2011, 6:23:58 PM11/9/11
to iSSH/iX11
5.10 has some minor corrections that should make Courier render more
appropriately on the iPhone and Inconsolata also render well on the
iPad.

I may actually switch to the old software rendering pipeline that I
had before iOS allowed for custom fonts. This was fairly accurate but
was a good bit slower. I'll see if I can optimize the code a little
more now that it's needed again.

Dean

SpencerC

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Jan 5, 2012, 9:47:10 AM1/5/12
to iSSH/iX11
Any updates on this?

Dean Beeler

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Jan 5, 2012, 1:20:02 PM1/5/12
to iSSH/iX11
There sure is. I've addressed the font rendering issue directly.
However presently I'm also working on several features in iSSH and I
want to make sure everything is solid before I do another release.
That being said, I am providing an ad hoc version to anyone who asks.
Just send me your UDID ( http://www.innerfence.com/howto/find-iphone-unique-device-identifier-udid
) directly and I'll send an updated version of iSSH to you by email as
soon as possible.

Dean
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