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Date: Mon, 08 Sep 2008 09:25:38 -0500
From: Anthony Liguori <anthony@codemonkey.ws>
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Subject: Re: [Qemu-devel] [PATCH 1 of 3] [UPDATE] vnc dynamic resolution
References: <48BFF02F.2000803@eu.citrix.com> <48C474FC.70608@codemonkey.ws>
	<48C5310E.5090506@eu.citrix.com>
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To: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: qemu-devel@nongnu.org

Stefano Stabellini wrote:
> Anthony Liguori wrote:
>   
>> "Red-max is the maximum red value (= 2n − 1 where n is the number of
>> bits used for red)."
>>
>> Is this just overzealous checks or was a fix for a broken client?
>>     
>
>
> This code is meant to convert pixels from the vnc server internal pixel
> format to the vnc client pixel format.
> red_max refers to the vnc client red max, while red_max1 refers to the
> vnc server internal red max.
> Before we were just handling the case red_max1 = 0xff, this code should
> be able to handle other cases as well (necessary for handling the shared
> buffer).
> Does this answer your question? May be with the assumption that red_max
> = 2^n - 1 is still possible to simplify the conversion code...
>   

Perhaps the source of my confusion is the use of red_max and red_max1.  
Could you try some more descriptive names?  I understand what the code 
is doing now but it's very easy to confuse the two masks.

Regards,

Anthony Liguori