Concerts Update

It's confirmed now, Dan Bern is performing in Ottawa Blues Fest on July 12th. A bit hard to get there in the middle of the week, but I'll try.

Although I missed the David Gilmour concert back in March, I was lucky enough to find two not-so-expensive tickets for Roger Waters on September 20 in Toronto. I attedned a Waters concert in 2002 where thousands of Iranian including me flew over from Tehran to Dubai to attend (photos). It's nice to be to one again.

Given the ticket I've reserved for GUADEC leaves me some time after the conference, I may even catch a Bob Dylan in concert in Germany. Talking about Bob, he turned 65 on Wednesday. Happy Birthday Bob!

Sara
by Bob Dylan

I laid on a dune, I looked at the sky,
When the children were babies and played on the beach.
You came up behind me, I saw you go by,
You were always so close and still within reach.

Sara, Sara,
Whatever made you want to change your mind?
Sara, Sara,
So easy to look at, so hard to define.

I can still see them playin' with their pails in the sand,
They run to the water their buckets to fill.
I can still see the shells fallin' out of their hands
As they follow each other back up the hill.

Sara, Sara,
Sweet virgin angel, sweet love of my life,
Sara, Sara,
Radiant jewel, mystical wife.

Sleepin' in the woods by a fire in the night,
Drinkin' white rum in a Portugal bar,
Them playin' leapfrog and hearin' about Snow White,
You in the marketplace in Savanna-la-Mar.

Sara, Sara,
It's all so clear, I could never forget,
Sara, Sara,
Lovin' you is the one thing I'll never regret.

I can still hear the sounds of those Methodist bells,
I'd taken the cure and had just gotten through,
Stayin' up for days in the Chelsea Hotel,
Writin' "Sad-Eyed Lady of the Lowlands" for you.

Sara, Sara,
Wherever we travel we're never apart.
Sara, oh Sara,
Beautiful lady, so dear to my heart.

How did I meet you? I don't know.
A messenger sent me in a tropical storm.
You were there in the winter, moonlight on the snow
And on Lily Pond Lane when the weather was warm.

Sara, oh Sara,
Scorpio Sphinx in a calico dress,
Sara, Sara,
You must forgive me my unworthiness.

Now the beach is deserted except for some kelp
And a piece of an old ship that lies on the shore.
You always responded when I needed your help,
You gimme a map and a key to your door.

Sara, oh Sara,
Glamorous nymph with an arrow and bow,
Sara, oh Sara,
Don't ever leave me, don't ever go.


Copyright © 1975 Ram's Horn Music

¶ 7:55 PM   1 comments

 Summer, Summer, Summer

Let me be the last to announce that Google Summer of Code results are out. Just click on organization names to see their accepted projects. In GNOME we got twenty projects. Vincent and Chris already wrote about it; the selection involved a few days of tough and lengthy discussions, on IRC and on mailing list, plus a closed election.

Anyway, we are all very excited about the chosen projects. I personally am the happy mentor of mathrick implementing Vertical Writing Support for Pango. Projects I really liked we could accept but we didn't were (in order of missing) Pango+XeTeX, Advanced OpenType and AAT Font Features for Pango and Font Manager. I'll be contacting those students (of which two are regular GNOME contributors) to see if they are interested in working on these out of Summer of Code.

I would like to specially thank Kosai (Chris Ball) and kikidonk (Raphaël Slinckx) for helping Vincent and I manage the GNOME side, and to Chris DiBona for the Google side of the thing.

And I know it's Summer when I fix the bike and get out cycling...

¶ 12:26 AM   2 comments

 

Valgrind hints for GLib: Finished the patch over the past week and it actually works now. The latest patch also fixes all of Federico's tasks for volunteers. Check it out.

Bugzilla Aliases: One feature of the updated GNOME Bugzilla that I didn't noticed previously is the alias field, where you can assign a name to a bug. The alias can be used when dupping bugs, or by URL surgery with the showbug.cgi.

Improved Font Rendering: As already noted by Edd, David Turner posted an impressive set of patches for cairo and Xft that drastically improve the quality of the subpixel text rendering.. Screenshot here, only makes sense to view using horizontal-RGB lcd display. Didn't test them yet, but looking forward to see them integrated.

Linus on CNN: I've not had read his interviews for a while. I like every word of what he says in this one. Update: And another interview. Pretty sane one again.


Random links and issues from my blogging backlog:

100000th character in ISO-10646 and Unicode: Uma Umamaheswaran writes 0D3D MALAYALAM PRASLESHAM (avagraha) has the unique honour of being the 100000 th character that has been accepted for possible inclusion in 10646 standard by JTC1/SC2.

Tango's Window Experiments: I would love to see windows that look and behave like those mockups.

Worldmapper: This is a collection of world maps, where territories are re-sized on each map according to the subject of interest, like population, economy, and a lot of other interesting measures. A pleasure to browse.

Kill Bill's Browser: Funniest "spread Firefox" page I've seen.

¶ 5:30 AM   3 comments

 Blogger: Dear Lazy Web

I seem to be too dumb to find where to report this. Next time you see blogger, please ask it to include a link to the relevant post in its comment mail it sends out if you configure it too.

Thanks
behdad

Update:

Seems like if you click the name f your blog at the end of the email, it will take you right to the particular post. I remember trying that when I hit this problem first and it didn't work. So things have changed.

¶ 11:24 PM   1 comments

 Series of Bugs

[Announcement: The deadline for submitting Google Summer of Code proposals is about 24 hours from now. We still have not got enough strong proposals for GNOME. If you are student, if you love GNOME, go ahead and submit. There's a looong list of ideas, and you are more than welcome to submit your own ideas.]

Since Gtk+ 2.8 moved to PangoCairo, there have been a few highly dupped irritating bugs all with the same theme of hinting and off-by-one issues. Past few weeks I managed to debug and bash them all. In the chronological order here they come, with their patches:

• Incorrect text rendering when in x86 64-bit precision mode. Filed as a cairo bug. The patch was something like this:
  

  -#define PANGO_UNITS(x) ((int)((x) * PANGO_SCALE))
  +#define PANGO_UNITS(x) ((int)((x) * PANGO_SCALE + 0.49999))

  (This probably would have been fixed by fixing the third bug in the list too.)
• Text is shifted off-by-one in Add to panel. Assigned to Pango, but libgnomecanvas highly suspected. Turned out it's a gdkpango bug. The patch was:

  -  cairo_move_to (cr, x / PANGO_SCALE, y / PANGO_SCALE);
  +  cairo_move_to (cr, (double)x / PANGO_SCALE, (double)y / PANGO_SCALE);

  After finding the bug, it became apparent that it only can happen if the next bug hits.
• Unhinted fonts are measured incorrectly and drawing problems occur as a result.

  +  /* fcfont's is_hinted controls metric hinting */
  +  PANGO_FC_FONT(cffont)->is_hinted =
  +    (cairo_font_options_get_hint_metrics(font_options) !=
  +     CAIRO_HINT_METRICS_OFF);

  Ironically I suggested this patch in December, but Owen said it wouldn't work AND the reporter said it didn't. It turned out this is the correct fix indeed.
• pango_layout_get_pixel_extents and pango_layout_get_pixel_size cause off-by-one metrics. This one was not reported and I opened myself, but was also raised in an email thread by Morten. I suspect the fix for this may have had some of the above bugs fixed, or maybe not. Anyway, it looks more correct now. The question to answer is how to round logical and ink rectangle metrics. The current code was simply rounding x, y, width, and height. Say your rounding function is f(.). There are two problems with this:
• First, f(x)+f(width) has twice the error of what you get for f(x+width). So I changed the width rounding to use (f(x+width) - f(x)) instead. Ditto for height.
  
• Next, shall we floor, round, or ceil? It used to round them all. Now we use separate functions for logical and ink extents.
  
  For ink rectangle, in Owen's words, the guarantee that we make is that you can render a layout onto a pixmap the size of its ink metrics and it won't get clipped. So I made it to floor x and y, and ceil x+width and y+height. The real thing looks like:

   int orig_x = ink_rect->x;
  int orig_y = ink_rect->y;
  
  ink_rect->x = PANGO_PIXELS_FLOOR (ink_rect->x);
  ink_rect->y = PANGO_PIXELS_FLOOR (ink_rect->y);
  
  ink_rect->width  = PANGO_PIXELS_CEIL (orig_x + ink_rect->width )
                   - ink_rect->x;
  ink_rect->height = PANGO_PIXELS_CEIL (orig_y + ink_rect->height)
                   - ink_rect->y;

  For logical rectangle, we are more interested that the rounded extents of adjacent chunks of text do not overlap or have any gaps. Which means, if x1+width1 = x2 before rounding, it should hold after rounding too. This means the same function f() should be used for x and x+width, and round() is the obvious choice here.
  
  I also audited gdkpango.c for places that roundings can be improved, not many more candidates, but there are a lot of PANGO_PIXELS and PANGO_SCALE occurences in gtk+/gtk. They all can use a pair of eyes, replacing some of them with PANGO_PIXELS_FLOOR or PANGO_PIXELS_CEIL.

Apparently I managed to not blog for two weeks. Hopefully this rather long post broke the thin ice.

¶ 9:56 PM   3 comments