[OpenJDK 2D-Dev] Another Xrender bug ..

[Dr Andrew John Hughes]

On 27 August 2010 21:25, Clemens Eisserer <linuxhippy at gmail.com> wrote:
> Hi again,
>
>>  Any thoughts on this one that just got submitted a few minutes ago?
>> I'm guessing you don't have a SPARC System with OpenSolaris handy
>> so I'm just asking for ideas here.
>
> The only thing I can think of is the copy code which copies/converts
> the GlyphInfo image-data into the stream submitted to X, in
> XRGlyphCacheEntry.writePixelData().
>
> I guess the pixel-data I get from the GlyphInfo structure is the same,
> maybe access using Unsafe is somehow broken or shifted by a byte?
> For now I assume a fixed oder when uploading the glyph-data (didn't
> find any docs about it), could it be different on that machine?
>

FWIW, SPARCs are big-endian.  Specifically,

'The 32-bit SPARC V8 architecture is purely big-endian. The 64-bit
SPARC V9 architecture utilizes big-endian instructions, but can access
data in either big-endian or little-endian byte order, chosen either
at the application instruction (load/store) level or at the memory
page level (via an MMU setting). The latter is often used for
accessing data from inherently little-endian devices, such as those on
PCI buses.' -- http://en.wikipedia.org/wiki/SPARC

> Thanks, Clemens
>
>
>> -phil.
>>
>> *Change Request ID*: 6980378
>> *Synopsis*: LCD subpixel text has yellow background with Xrender enabled in
>> jdk1.7.0-ea-b106 on SPARC.
>>
>> === *Description*
>> ============================================================
>> Java Version: 1.7.0-ea-b106
>> Platform: OpenSolaris 5.11 snv_146
>>
>> Problems:
>> When launch Java2Demo/SwingSet2 with Xrender=True or true in b106, you can
>> see all letters or fonts are marked with yellow color or yellow background,
>> but disable xrender, it looks normal, no yellow background, please see
>> attached files for xrender enabled and disabled screen shots for details.
>>
>> File this bug to make sure that this is not a problem caused by xrender
>> enabled.
>>
>> It can be reproducible as alway by the following command:
>> bin/java -jar -Dsun.java2d.xrender=True demo/jfc/Java2D/*.jar
>>
>> We have a OpenSolaris 5.11 snv_146 newly installed in lab, the host name is
>> listed in comments if you want to reproduce it.
>>
>> The framebuffer in the machine is XVR-100.
>>
>> *** (#1 of 1): 2010-08-26 21:55:21 GMT+00:00 tao.t.zhang at oracle.com
>> *** Last Edit: 2010-08-26 22:46:10 GMT+00:00 tao.t.zhang at oracle.com
>>
>> === *Evaluation*
>> =============================================================
>> The background that is yellow follows the rectangular shape of the
>> individual glyphs. Otherwise everything appears correct.
>> Seeing this only on SPARC. At this time there's only one system
>> here with the right hardware/software combination to run XRender
>> on SPARC so it could be an Xserver side problem.
>>
>> Its not been seen on Solaris on Intel and it also doesn't occur
>> on software buffered images, only on XRender surfaces.
>>
>>
>>
>



-- 
Andrew :-)

Free Java Software Engineer
Red Hat, Inc. (http://www.redhat.com)

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