Warp schrieb:
>> Likewise, how to pre-gamma-correct color values from
>> other programs (such as color pickers).
> 
>   About that... I wonder if POV-Ray should offer some kind of function to
> do that, for convenience. In the same way as eg. degrees() and radians()
> exist for convenience, even though they don't really save a whole lot of
> work compared to if they didn't exist.

I think that definitely yes, POV-Ray should have such a feature. It is 
perfectly possible to roll your own macro to do that, but if POV-Ray is 
going the full way for proper gamma handling, it should - I'd even say 
/must/ - provide some standard procedure to do it, if only to make a 
clear statement along the lines of "yes, /this/ is the right way to deal 
with it". And I'd go as far as to say that it should work without having 
to include a particular file, so it should be a built-in language 
contruct, not just a macro.

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"clipka" <ano### [at] anonymousorg> schreef in bericht 
news:4aa43552$1@news.povray.org...
>
> I think that definitely yes, POV-Ray should have such a feature. It is 
> perfectly possible to roll your own macro to do that, but if POV-Ray is 
> going the full way for proper gamma handling, it should - I'd even say 
> /must/ - provide some standard procedure to do it, if only to make a clear 
> statement along the lines of "yes, /this/ is the right way to deal with 
> it". And I'd go as far as to say that it should work without having to 
> include a particular file, so it should be a built-in language contruct, 
> not just a macro.

Sven Littkovski's neat little "POV-Ray Color Picker" (2006; version 2.0) is 
a good example of such a picker. I use it quite a lot and I recommend it 
warmly. Built into POV-Ray would be a nice addition.

Thomas

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Thomas de Groot schrieb:
>> And I'd go as far as to say that it should work without having to 
>> include a particular file, so it should be a built-in language contruct, 
>> not just a macro.
> 
> Sven Littkovski's neat little "POV-Ray Color Picker" (2006; version 2.0) is 
> a good example of such a picker. I use it quite a lot and I recommend it 
> warmly. Built into POV-Ray would be a nice addition.

Well, I wasn't thinking about a built-in color picker, but a built-in 
language syntax for gamma conversion.

Of course having its own built-in color picker would be a neat feature 
(and I do second this idea), but for instance on Unix systems, where 
POV-Ray does not come with an "IDE", a feature built into the SDL to 
perform gamma conversion math would still be required.

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Thomas de Groot wrote:
> Sven Littkovski's neat little "POV-Ray Color Picker" (2006; version 2.0) is 
> a good example of such a picker. I use it quite a lot and I recommend it 
> warmly. Built into POV-Ray would be a nice addition.
> 

Are you aware that this tool (like most others) will not apply the 
required inverse gamma correction and will result in the usual washed 
out colors similar to jpeg image maps when used with 3.7 or 
assumed_gamma 1.0 ?
And to mention it again: wrong gamma correction does not only give wrong 
brightness intensities, it changes also the hue.

-Ive

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"Ive" <"ive### [at] lilysoftorg"> schreef in bericht 
news:4aa4f79e@news.povray.org...
> Thomas de Groot wrote:
>> Sven Littkovski's neat little "POV-Ray Color Picker" (2006; version 2.0) 
>> is a good example of such a picker. I use it quite a lot and I recommend 
>> it warmly. Built into POV-Ray would be a nice addition.
>>
>
> Are you aware that this tool (like most others) will not apply the 
> required inverse gamma correction and will result in the usual washed out 
> colors similar to jpeg image maps when used with 3.7 or assumed_gamma 1.0 
> ?
> And to mention it again: wrong gamma correction does not only give wrong 
> brightness intensities, it changes also the hue.
>

Ah... yes...? I had not really/consciously thought of that... This means 
that picking a color from a RGB/HSL color chart in any paint application 
will show this problem?

Thomas

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Thomas de Groot wrote:
> Ah... yes...? I had not really/consciously thought of that... This means 
> that picking a color from a RGB/HSL color chart in any paint application 
> will show this problem?
> 

Yes. Unless it does not explicit state that the working color space is a 
linear one like e.g. scRGB (note the 'c'). You can use the histogram 
window of IC and move the mouse across the viewing window to get the 
color value of images in scRGB that could be used directly within 
POV-Ray. Press CTRL + left mouse button to 'lock' any value. This makes 
it easier when you move the mouse to the POV editor for writing the 
value down ;)
Should I add the possibility to copy the color value directly to the 
clipboard?

-Ive

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"Ive" <"ive### [at] lilysoftorg"> schreef in bericht 
news:4aa4fcf0@news.povray.org...
>
> Yes. Unless it does not explicit state that the working color space is a 
> linear one like e.g. scRGB (note the 'c'). You can use the histogram 
> window of IC and move the mouse across the viewing window to get the color 
> value of images in scRGB that could be used directly within POV-Ray. Press 
> CTRL + left mouse button to 'lock' any value. This makes it easier when 
> you move the mouse to the POV editor for writing the value down ;)

I had not yet found that in IC (shame on me)

> Should I add the possibility to copy the color value directly to the 
> clipboard?

Yes, that would be excellent.

Thomas

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By the way, there is a "palette" option in IC, but it is greyed out. How can 
we use it? That would be the correct color picker...

Thomas

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Thomas de Groot schrieb:
> By the way, there is a "palette" option in IC, but it is greyed out. How can 
> we use it? That would be the correct color picker...

I guess that's for GIF files and such, so maybe not what you seem to 
expect ;-)

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"clipka" <ano### [at] anonymousorg> schreef in bericht 
news:4aa60e3b$1@news.povray.org...
> I guess that's for GIF files and such, so maybe not what you seem to 
> expect ;-)

Oh pity.... I had high hopes..... :-)

I would like a *correct* palette as a color picker...

Thomas

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