87664 - before bitmap scaling look for other font foundries

Status: RESOLVED FIXED

(Core :: Layout, defect)

Description

[tenthumbs]

Mozilla needs to look outside the font foundry for fonts, particularly 
large ones. Right now it always sticks with one foundry.  My default font 
is helvetica so mozilla uses -adobe-helvetica-* fonts using scaled bitmap 
variants when it wants to. Not surprisingly, that looks crappy.

It could look better because I have scalable type1 helvetica fonts 
available. If fact there listed before the scaled bitmap ones. The font 
path goes
  /usr/X11R6/lib/X11/fonts/75dpi/:unscaled
  ...
  /usr/X11R6/lib/X11/fonts/urw/
  /usr/X11R6/lib/X11/fonts/Math/Mathematica/type1 
  ...
  /usr/X11R6/lib/X11/fonts/75dpi
so xlsfonts shows
  -adobe-helvetica-bold-o-normal--10-100-75-75-p-60-iso8859-1
  [ a bunch more unscaled bitmap varieties ]
  -adobe-helvetica-medium-r-normal--34-240-100-100-p-176-iso8859-1
  -urw-helvetica-bold-o-normal--0-0-0-0-p-0-iso8859-1
  -urw-helvetica-bold-r-normal--0-0-0-0-p-0-iso8859-1
  -urw-helvetica-medium-o-normal--0-0-0-0-p-0-iso8859-1
  -urw-helvetica-medium-r-normal--0-0-0-0-p-0-iso8859-1
  -wri-helvetica-bold-o-normal--0-0-0-0-p-0-iso8859-1
  -wri-helvetica-bold-r-normal--0-0-0-0-p-0-iso8859-1
  -wri-helvetica-medium-o-normal--0-0-0-0-p-0-iso8859-1
  -wri-helvetica-medium-r-normal--0-0-0-0-p-0-iso8859-1
  [ repeated unscaled adobe varieties ]
  -adobe-helvetica-bold-o-normal--0-0-100-100-p-0-iso8859-1
  -adobe-helvetica-bold-r-normal--0-0-100-100-p-0-iso8859-1
  -adobe-helvetica-medium-o-normal--0-0-100-100-p-0-iso8859-1
  -adobe-helvetica-medium-r-normal--0-0-100-100-p-0-iso8859-1

So, when it's looking for a largish font, say 42pt, it ignores the
scalable URW and WRI fonts and goes for the ugly scaled bitmaps. Using
http://bugzilla.mozilla.org/showattachment.cgi?attach_id=39772 as an
example, mozilla goes for this:

loaded -adobe-helvetica-medium-r-normal--8-80-75-75-p-46-iso8859-1
loaded -adobe-helvetica-medium-r-normal--10-100-75-75-p-56-iso8859-1
loaded -adobe-helvetica-medium-r-normal--18-180-75-75-p-98-iso8859-1
loaded -adobe-helvetica-medium-r-normal--24-240-75-75-p-130-iso8859-1
loaded -adobe-helvetica-medium-r-normal--31-*-*-*-p-*-iso8859-1
loaded -adobe-helvetica-medium-r-normal--32-*-*-*-p-*-iso8859-1
loaded -adobe-helvetica-medium-r-normal--33-*-*-*-p-*-iso8859-1
loaded -adobe-helvetica-medium-r-normal--34-*-*-*-p-*-iso8859-1
loaded -adobe-helvetica-medium-r-normal--35-*-*-*-p-*-iso8859-1
loaded -adobe-helvetica-medium-r-normal--36-*-*-*-p-*-iso8859-1
loaded -adobe-helvetica-medium-r-normal--37-*-*-*-p-*-iso8859-1
loaded -adobe-helvetica-medium-r-normal--38-*-*-*-p-*-iso8859-1
loaded -adobe-helvetica-medium-r-normal--39-*-*-*-p-*-iso8859-1
loaded -adobe-helvetica-medium-r-normal--40-*-*-*-p-*-iso8859-1
loaded -adobe-helvetica-medium-r-normal--41-*-*-*-p-*-iso8859-1
loaded -adobe-helvetica-medium-r-normal--42-*-*-*-p-*-iso8859-1
loaded -adobe-helvetica-medium-r-normal--43-*-*-*-p-*-iso8859-1
loaded -adobe-helvetica-medium-r-normal--44-*-*-*-p-*-iso8859-1
loaded -adobe-helvetica-medium-r-normal--45-*-*-*-p-*-iso8859-1
loaded -adobe-helvetica-medium-r-normal--46-*-*-*-p-*-iso8859-1
loaded -adobe-helvetica-medium-r-normal--47-*-*-*-p-*-iso8859-1
loaded -adobe-helvetica-medium-r-normal--48-*-*-*-p-*-iso8859-1
loaded -adobe-helvetica-medium-r-normal--49-*-*-*-p-*-iso8859-1
loaded -adobe-helvetica-medium-r-normal--51-*-*-*-p-*-iso8859-1
loaded -adobe-helvetica-medium-r-normal--52-*-*-*-p-*-iso8859-1

Lots of ugliness there.

Comment 1

[kill this account]

interesting idea: before chosing a bitmap scaled font wildcard the foundry and 
search for a better fit.

Comment 2

[kill this account]

Attachment: patch; look for an outline font from alternate foundry instead of a bitmap scaled font

Comment 3

[kill this account]

this patch looks for an outline scaled font from any foundry in place of a
bitmap scaled font.

Unfortunately, the -adobe-helvetica-medium-r-normal--0-0-0-0-p-*-iso8859-1 looks
awful at large sized.

Comment 4

[kill this account]

Attachment: adobe-helvetica outline scaled font at 52 pixel (it is ugly)

Comment 5

[kill this account]

The image above is *not* magnified. It was taken by "xmag -mag 1". 

At small pixel sizes the adobe-helvetica looks good while the wri-helvetica
looks jaggy.

Oddly, at larger sizes the adobe-helvetica font is jaggy/ugly at while the
wri-helvetica looks pretty good. 

Very strange.

Comment 6

[tenthumbs]

Attachment: large-fonts-1.zip; an example

Comment 7

[tenthumbs]

FWIW, I've attached an example of how mozilla displays scalable and scaled
bitmap fonts at large sizes. I had to add some font aliases so that I could
specify exactly which fotn to use but it does give the idea. For 28pt, mozilla
decided to use a 24pt bitmap font which is why it's smaller. That's the only
exception.

Comment 8

[kill this account]

The patch in attachment 40228 [details] [diff] [review] does not work. I thought if I asked for a font
with this spec "-*-%s-%s-%s-%s-%s-0-0-0-0-%s-*-%s" it would return an 
outline scaled font. Not true. Hence the what I thought were outline scaled
adobe-helvetica glyphs were in fact bitmap scaled.

Comment 9

[kill this account]

The current Mozilla font code has two layers:

 1) select a foundry/family that can display the glyph

 2) select a size within that foundry/family

So when the code finds out that only a bitmap scaled font will work
we are not at a level where we can choose a different foundry or
family.

Maybe if I added a test to the upper loop, wouldBitmapScale, it could
then check other foundries before accepting the bitmap scaled font.

Comment 10

[kill this account]

I believe that bug 94327 will solve the most common cases of this bug.

Comment 11

[kill this account]

--> ftang

Comment 12

[Frank Tang]

bulk move NEW FUTURE bug to ASSIGN

Comment 13

[kill this account]

now that bug 94327 is fixed this should be fixed