169556 - RFE: Use XLFD matrix transformation to generate italic/oblique versions if font family does not have that style

Status: NEW

(Core :: Graphics: Text, enhancement)

Description

[Roland Mainz]

RFE: Use XLFD matrix transformation to generate italic/oblique versions if font
family does not have that style.

Some font families (like Solaris 2.8's gb18030-2000 font 
-fangzheng-song-medium-r-normal--0-0-0-0-m-0-gb18030.2000-*) do not have special
italic/oblique versions.
It may be usefull to "emulate" italic&co. by using a transformation matrix on
the same font to generate the missing styles.

Comment 1

[kill this account]

Interesting idea.

Does anyone know if matrix transformated fonts are attractive or unattractive?

Do we know if X servers support this?

An alternate to matrix tranformation could be AA transformed glyphs.

Comment 2

[kill this account]

Roland: should this bug be assigned to you?

Comment 3

[John Morrison]

-> [e-mail]

Comment 4

[Roland Mainz]

Brian Stell wrote:
> Does anyone know if matrix transformated fonts are attractive or unattractive?

Outline font quality should AFAIK not suffer if a transformation matrix gets
applied - but bitmap fonts may not like all transformations (for example:
rotation by 90° looks fine, rotation by 97° doesn't look very good (with small
bitmap fonts)). Finding good values for the matrix to may require some
testing...

> Do we know if X servers support this?

Transformation matrix support was added in X11R6 which is AFAIK the standard for
all modern X11 implementations (even plain old Solaris 2.6 supports it).

> An alternate to matrix tranformation could be AA transformed glyphs.

Ugh. The problem is that we would have to implement our own matrix
transformation code in Mozilla...

Comment 5

[Roland Mainz]

Brian Stell wrote:
> should this bug be assigned to you?

Sure, I can take it...
... but I need a way to figure out if a font family alreads has an
italic/oblique version of the font or not.

Any ideas ?

Comment 6

[kill this account]

in nsFontNode::FillStyleHoles() the code "finds" a substitute for missing
italic fonts

Comment 7

[Roland Mainz]

Brian Stell wrote:
> in nsFontNode::FillStyleHoles() the code "finds" a substitute for missing
> italic fonts

... that place would mean we would have to keep a copy of the decomposed XLFD
somewhere around (we need it to build a new XLFD with the transformation matrix
applied) ... ;-(

Comment 8

[kill this account]

or separate out the code that decomposes the XLFD so it can be shared by both
GetFontNames() and your new code.

Comment 9

[BugBot [:suhaib / :marco/ :calixte]]

The bug assignee didn't login in Bugzilla in the last 7 months.
:enndeakin, could you have a look please?
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