[HarfBuzz] hb-view hb-shape documentation

[Eduardo Castineyra]

More on this:

I replaced hb_buffer_set_script and hb_buffer_set_language with a call 
to hb_buffer_guess_segment_properties in my own code, but no magic 
happened as in hb-shape :(

El 01/10/2013 12:34, Eduardo Castineyra escribió:
> HI Behdad,
>
> I also have realized hb_shapes passes hb_buffer_set_script and 
> hb_buffer_set_language default parameters unless the user specifies 
> the opposite.
>
> Does that mean harfbuzz automagically detects the language? Isn't that 
> what the itemizer was supposed to do?
>
> Regards!
>
> El 30/09/2013 19:00, Behdad Esfahbod escribió:
>> On 13-09-30 05:38 AM, Eduardo Castineyra wrote:
>>> Thanks Behdad,
>>>
>>> Why is there a space at the beginning of the glyph list? (I attached 
>>> the
>>> thai.txt file)
>> Because your file has a "BOM" (U+FEFF) character at the beginning.  With
>> UTF-8, that usage is discouraged as far as I know.  At any rate, the 
>> space has
>> zero advance and hence is invisible.
>>
>> b
>>
>>
>>> El 27/09/2013 18:41, Behdad Esfahbod escribió:
>>>> On 13-09-27 12:36 PM, Eduardo Castineyra wrote:
>>>>> This is the json file I got:
>>>>>
>>>>> hb-shape --font-file=leelawad.ttf --text-file=thai.txt 
>>>>> --output-format=json
>>>>> --output-file=thaiglyphs.txt --shapers=ot
>>>>>
>>>>> [{"g":"space","cl":0,"dx":0,"dy":0,"ax":0,"ay":0},{"g":"uni0E2B","cl":1,"dx":0,"dy":0,"ax":1207,"ay":0},{"g":"uni0E49","cl":1,"dx":217,"dy":0,"ax":0,"ay":0},{"g":"uni0E31","cl":1,"dx":114,"dy":500,"ax":0,"ay":0},{"g":"space","cl":4,"dx":0,"dy":0,"ax":1122,"ay":0},{"g":"uni0E2B","cl":5,"dx":0,"dy":0,"ax":1207,"ay":0},{"g":"uni0E31","cl":5,"dx":114,"dy":0,"ax":0,"ay":0},{"g":"space","cl":7,"dx":0,"dy":0,"ax":1122,"ay":0},{"g":"uni0E2B","cl":8,"dx":0,"dy":0,"ax":1207,"ay":0},{"g":"uni0E49","cl":8,"dx":217,"dy":0,"ax":0,"ay":0},{"g":"space","cl":10,"dx":0,"dy":0,"ax":1122,"ay":0},{"g":"uni0E2B","cl":11,"dx":0,"dy":0,"ax":1207,"ay":0},{"g":"uni0E31","cl":11,"dx":114,"dy":0,"ax":0,"ay":0},{"g":"uni0E49.sm","cl":11,"dx":114,"dy":500,"ax":0,"ay":0}] 
>>>>>
>>>>>
>>>>> I see the cluster, the deltas, the advances, but I'm still missing 
>>>>> the glyph
>>>>> indices for the font. Do you know what "uni0E49.sm" means?
>>>> Those are glyph names.  Pass --no-glyph-names to get raw glyph 
>>>> number instead.
>>>>
>>>>
>>>>> El 26/09/2013 20:23, Khaled Hosny escribió:
>>>>>> Use --output-format=json, should be a bit more explanatory. 
>>>>>> Myself, I
>>>>>> often forget which number is which, but you basically get glyph 
>>>>>> name,
>>>>>> cluster value, X and Y advance and delta.
>>>>>>
>>>>>> The glyph name is equivalent to glyph index, just a bit more 
>>>>>> readable.
>>>>>> The cluster value is basically the index of the corresponding 
>>>>>> character
>>>>>> in the input string (though the relation can be complex). The 
>>>>>> advances
>>>>>> and deltas are what HarfBuzz clients will use to calculate the 
>>>>>> absolute
>>>>>> glyph position, HarfBuzz itself does not do that.
>>>>>>
>>>>>> Regards,
>>>>>> Khaled
>>>>>>
>>>>>> On Thu, Sep 26, 2013 at 07:51:20PM +0200, Eduardo Castineyra wrote:
>>>>>>> Now I see it, thanks!
>>>>>>>
>>>>>>> How should I interpret the outcome for hb-shape?
>>>>>>>
>>>>>>>> hb-shape leelawad.ttf --text-file=thai.txt
>>>>>>> [space=0+0|uni0E2B=1+1207|uni0E49=1 at 217,0+0|uni0E31=1 at 114,500+0|space=4+1122|uni0E2B=5+1207|uni0E31=5 at 114,0+0|space=7+1122|uni0E2B=8+1207|uni0E49=8 at 217,0+0|spac 
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> e=10+1122|uni0E2B=11+1207|uni0E31=11 at 114,0+0|uni0E49.sm=11 at 114,500+0] 
>>>>>>>
>>>>>>>
>>>>>>> What I would expect to see was the unicode, the index of the glyph
>>>>>>> inside the leelawad.ttf font, and the screen position of the glyph.
>>>>>>> But I don't what those numbers and symbols mean.
>>>>>>>
>>>>>>> El 26/09/2013 19:27, Khaled Hosny escribió:
>>>>>>>> On Thu, Sep 26, 2013 at 06:48:26PM +0200, Eduardo Castineyra 
>>>>>>>> wrote:
>>>>>>>>> Hi,
>>>>>>>>>
>>>>>>>>> I was trying to use the hb-view and hb-shape tools but I don't 
>>>>>>>>> get
>>>>>>>>> how do they work.
>>>>>>>>>
>>>>>>>>> This is the output I got from hb-view, is there any 
>>>>>>>>> documentation to
>>>>>>>>> know what can I do with the outcome?
>>>>>>>> If you don't specify an output file name, hb-view will do some 
>>>>>>>> sort of
>>>>>>>> Unicode-art to draw the glyphs on the terminal. This works fine on
>>>>>>>> Unicode-capable terminals, but I guess Windows’s cmd.exe is not 
>>>>>>>> such a
>>>>>>>> one.  You can specify the output file name and format 
>>>>>>>> explicitly, see
>>>>>>>> hb-view --help.
>>>>>>>>
>>>>>>>> Regards,
>>>>>>>> Khaled
>>>>> _______________________________________________
>>>>> HarfBuzz mailing list
>>>>> HarfBuzz at lists.freedesktop.org
>>>>> http://lists.freedesktop.org/mailman/listinfo/harfbuzz
>
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