[9fans] max width of image, CHUNK limit

[9fans] max width of image, CHUNK limit

[okamoto]

We met the maximum value of CHUNK of /sys/src/libdrawloadimage.c 
for certain image with 32 bit depth.  I think this limit comes from current 9p
protocol.
Does this limit goes larger in the next 9p2000 version?

I know we can avoid this limit in our application, however, if that limit goes
away, it'll be more beautiful...

Kenji

Re: [9fans] max width of image, CHUNK limit

[okamoto]

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Thank you very much Russ.
Now, we are headding your second method.
In 9p2000, we may have a more elegant program here.

Kenji


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From: "Russ Cox" <rsc@plan9.bell-labs.com>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] max width of image, CHUNK limit
Date: Tue, 12 Feb 2002 01:02:31 -0500
Message-ID: <d3107af4f35b5340f9e056b8a4ba0c2f@plan9.bell-labs.com>

Yes, in 9P2000 the maximum message size
may be as large as the two sides wish to negotiate.
We typically run with a 32kb message size
for cpu connections, specifically to help /dev/draw.
You could lift the current restriction by changing
cloadimage and the image compressor
to expect rectangles rather than y-coordinate pairs
when the image is very wide.  Another less involved
possibility is to write the image as a sequence of 
images, one for each medium sized column.

With appropriate reworking, the limit should
really go away entirely.

Russ

Re: [9fans] max width of image, CHUNK limit

[Russ Cox]

Yes, in 9P2000 the maximum message size
may be as large as the two sides wish to negotiate.
We typically run with a 32kb message size
for cpu connections, specifically to help /dev/draw.
You could lift the current restriction by changing
cloadimage and the image compressor
to expect rectangles rather than y-coordinate pairs
when the image is very wide.  Another less involved
possibility is to write the image as a sequence of 
images, one for each medium sized column.

With appropriate reworking, the limit should
really go away entirely.

Russ