MantisBT - VTK
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IDProjectCategoryView StatusDate SubmittedLast Update
0010052VTK(No Category)public2009-12-14 15:402016-08-12 09:55
ReporterSean McBride 
Assigned ToKitware Robot 
PrioritynormalSeveritymajorReproducibilityalways
StatusclosedResolutionmoved 
PlatformOSOS Version
Product Version 
Target VersionFixed in Version 
Project
Type
Summary0010052: newer freetypes render differently and breaks VTK unit tests / VTK fonts are incorrect(?)
DescriptionIf you use VTK_USE_SYSTEM_FREETYPE and your freetype is 2.3.6 or newer, some VTK unit tests will fail. See attached images.

This problem exists, but is worked around, in VTK's CVS version of freetype (2.3.11 at this time).

After painstaking regression through freetype CVS, the source of the problem was committed on 2008-05-18:

    * src/pshinter/pshalgo.c (ps_hints_apply): Reset scale values after
    correction for pixel boundary. Without this patch, the effect can
    be cumulative under certain circumstances, making glyphs taller and
    taller after each call. This fixes Savannah bug #19976.

https://savannah.nongnu.org/bugs/?19976 [^]

Werner (a freetype dev) thinks: "I suspect that the font is badly hinted; it seems to miss hints (both ghost and normal) at least for the `i'. This, in combination with a not-yet fixed problem within FreeType (which sometimes displaces horizontal strokes too much vertically) probably causes the effects you can see."

We need to convert the VTK C++-ified fonts to a standard format so that Werner can debug. I have no idea how. Anyone?
Steps To Reproduce
Additional Information
TagsNo tags attached.
Relationships
related to 0007199closed Sean McBride VTK's freetype is out of date. Currently version 2.3.6 includes security fixes. 
related to 0008513closed Sean McBride VTK's freetype is out of date: 2.3.7 is used, 2.3.11 is current 
Attached Filespng multiLineText2.3.5.png (15,969) 2009-12-14 15:41
https://www.vtk.org/Bug/file/7722/multiLineText2.3.5.png
png

png multiLineText2.3.7.png (15,150) 2009-12-14 15:42
https://www.vtk.org/Bug/file/7723/multiLineText2.3.7.png
png
Issue History
Date ModifiedUsernameFieldChange
2009-12-14 15:40Sean McBrideNew Issue
2009-12-14 15:41Sean McBrideRelationship addedrelated to 0007199
2009-12-14 15:41Sean McBrideFile Added: multiLineText2.3.5.png
2009-12-14 15:42Sean McBrideFile Added: multiLineText2.3.7.png
2009-12-14 15:42Sean McBrideRelationship addedrelated to 0008513
2009-12-17 11:01Sean McBrideNote Added: 0018941
2011-06-16 13:11Zack GalbreathCategory => (No Category)
2016-08-12 09:55Kitware RobotNote Added: 0037129
2016-08-12 09:55Kitware RobotStatusexpired => closed
2016-08-12 09:55Kitware RobotResolutionopen => moved
2016-08-12 09:55Kitware RobotAssigned To => Kitware Robot

Notes
(0018941)
Sean McBride   
2009-12-17 11:01   
from Werner:

"I'm now rather convinced that there is no bug. I've attached
a small PDF file which uses uagk8a.pfb as in the two
multiLineText images, displaying the two letter `S' and `e'.
I've also attached an image of acroread 7.0.8 (on GNU/Linux),
rendering the small document so that the glyphs have
approximately the same size. It looks (almost) the same as with
FreeType 2.3.7 -- considering acroread as one of the reference
implementations for rendering PS fonts natively, I doubt that
this result can be improved. "
(0037129)
Kitware Robot   
2016-08-12 09:55   
Resolving issue as `moved`.

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