bugThe FreeType Project - Bugs: bug #29017, MIRP instruction under ROFF

 
 

You are not allowed to post comments on this tracker with your current authentication level.

bug #29017: MIRP instruction under ROFF

Submitter:  Andrey V. Panov <panov>
Submitted:  Sat 27 Feb 2010 12:47:35 AM UTC
   
 
Severity:  3 - Normal Item Group:  Incorrect behaviour
Status:  Invalid Privacy:  Public
Assigned to:  wl Open/Closed:  Closed
Planned Release:  None

Tue 02 Mar 2010 06:26:08 AM UTC, comment #3: 

OK.  I'm marking this report as invalid.

Werner LEMBERG <wl>
Group administrator
Tue 02 Mar 2010 05:38:20 AM UTC, comment #2: 

Ok, it seems you are right.

Andrey V. Panov <panov>
Sat 27 Feb 2010 08:12:08 AM UTC, comment #1: 

I think FreeType does it right, and the problem has nothing to do with rounding (which FreeType does correctly, BTW).  For the MIRP instruction, the distance between the reference point and point 7 is measured along the dual_projection_vector (see explanation in SDPVTL), and this vector uses coordinates before grid-fitting takes place.

And indeed, using raw coordinates, the cut-in value does not allow the displacement.

Perhaps the documentation in the FontForge's instruction gloss window should be improved.

BTW, have you compared the result with the MS rasterizer?  Is there a difference?

Werner LEMBERG <wl>
Group administrator
Sat 27 Feb 2010 12:47:35 AM UTC, original submission:  

In instructions of "afii10033" (П) at 19 ppem and antialiasing MIRP instruction moving point No. 7 against No. 1 (line 87 in fontforge's tt debugger) should move point No. 7 to x=10.81 pixels, but freetype moves it to x=12.17 pixels. The round state is set to "off", cvt cut in (1.06px) allows this displacement. According to specs from MS site (ttinst2.doc) "The c Boolean above controls both rounding and the use of Control Value Table entries. If you would like the meaning of this Boolean to specify only whether or not the MIRP[ ] instruction should look at the control_value_cut_in, use the ROFF[ ] instruction to turn off rounding. In this manner, it is possible to specify rounding off and no cut_in."

After setting this value to 0 as is done in "H" freetype moves the point to right position using control value No. 58.

Andrey V. Panov <panov>

 

(Note: upload size limit is set to 16384 kB, after insertion of the required escape characters.)

Attached Files
file #19806:  Istok-Regular.ttf added by panov (173KiB - application/x-font-ttf - test font)

 

Depends on the following items: None found

Items that depend on this one: None found

 

Carbon-Copy List
  • -email is unavailable- added by wl (Posted a comment)
  • -email is unavailable- added by panov (Submitted the item)
  •  

    There are 0 votes so far. Votes easily highlight which items people would like to see resolved in priority, independently of the priority of the item set by tracker managers.

     

    Follow 5 latest changes.

    Date Changed by Updated Field Previous Value => Replaced by
    2010-03-02 wl StatusNeed Info Invalid
        Open/ClosedOpen Closed
    2010-02-27 wl StatusNone Need Info
        Assigned toNone wl
    2010-02-27 panov Attached File- Added Istok-Regular.ttf, #19806

    Back to the top

    Powered by Savane 3.13-d3ae.
    Corresponding source code