Re: sRGB color support in NS port [PATCH]

[Jan Djärv]

Hello.

21 dec 2013 kl. 18:37 skrev Steve Purcell <address@hidden>:

> On 21 Dec 2013, at 16:16, Jan Djärv <address@hidden> wrote:
> 
> 
>> Also, this is not what the documentation says is the right way to display 
>> colors on OSX.
> 
> 
> That’s actually not at all clear to me from the docs: I haven’t found 
> anything which says that programs may only accept from users hex colour 
> literals in the calibrated RGB space.  The docs appear to simply say that 
> that is the space to use within NS programs for shuffling R, G and B values 
> around.  What we’re talking about here is how to interpret user colour input, 
> and how to display colours back to the user as RGB triplets.
> 

They don't say "may only", but suggests calibrated color space to overcome 
differences between monitors.
Two different monitor should in theory display the same sRGB color the same.  
In practice this is seldom so.  So you calibrate each monitor individually to 
get the same color.


> To be useful, the user-oriented RGB notation should presumably denote colours 
> which will be displayed consistently on all machines. For that to be even be 
> possible, those colours must be in an absolute and standard colour space.

This only applies if all display devices output sRGB the same.  They don't.  
Also, sRGB has a limited color range, some wants to go beyond this range 
(gaumut I think it is called).  Adobe has some RGB color spaces that contains 
more colors than sRGB for example.

> 
> On Windows, the RGB colour literals will be assumed to be coordinates within 
> its default sRGB space. On OS X, emacs will claim that they are in the vague 
> “calibrated” space, which is not sRGB, so they will automatically look 
> different between the two platforms. This seems like a shortcoming to me, and 
> it’s not clear to me that making the color space a user preference is the 
> correct fix, at least if the default is the calibrated space.

Well, OSX doesn't use \ in paths like Windows either, not does it use 16 bit 
chars in API:s and a bunch of other differences.  Saying X does something, 
therefore we must do like X is a nonsense argument.

        Jan D.