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Re: darkening colour

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W dniu wtorek, 7 kwietnia 2015 09:51:16 UTC+2 użytkownik fir napisał:
> W dniu poniedziałek, 6 kwietnia 2015 22:05:30 UTC+2 użytkownik Bart napisał:
> > On 06/04/2015 17:44, fir wrote:
> > > W dniu poniedziałek, 6 kwietnia 2015 17:02:28 UTC+2 użytkownik Bart napisał:
> > 
> > >> I don't know what I'm supposed to be looking at here. What is the
> > >> problem you're trying to solve? Are any of these before and after?
> > >>
> > >> But the rendering is crude enough that I doubt many will notice if the
> > >> colour balance is a bit off.
> > >>
> > >> Some of the objects do have garish (ie. highly saturated) colours, but
> > >> that would just be a bad choice of base colour: you can 'desaturate' by
> > >> choosing a different colour. You do't need to deal with it by complex
> > >> real-time per-pixel transformations.
> > >>
> > >
> > > So you tested it? (I thought nobody was testing it as they afraid of malware)
> > > Desaturation routine is seen when toggle 'q'
> > 
> > Sure.
> > 
> > > The problem? I want to general improve visual quality - thus i feel a need to test variious options etc
> > > Esp darkening/brightening i could use when doing shading of triangles to see if effect is
> > > not a bit better/more clear
> > 
> > OK, pressing Q in program22 and 23 (I can't remember 24), gives a 
> > gradual fade to black&white over the image.
> > 
> > If that's all you want, then I'm fairly certain that the simple 
> > luminance formula (the one that could be reduced to lookups) will work 
> > just as well.
> > 
> > But if you're concerned about the appearance, I'm not sure that's the 
> > right approach. If you don't want strong colours, then just start with 
> > less saturated colours in the first place! It doesn't look like you're 
> > attempting photo-realism so a 1% difference in correct colour balance is 
> > not going to be important.
> > 
> > There are also a lot of artefacts in the shading (especially on the 
> > solar panels of the space vehicle, if that's what they are) that could 
> > do with looking at.
> > 
> 
> as i said desaturation is not of my concern 
> now.. I need up-saturation, proper dargening, brighting, changing hue, and other potentially usable effects
> 
> (this prog of my is not only prog (some early prototype of some game) but also demo
> of my graphics library, Im working on both
> 
> in general i need improve efficiency and improve quality (maybe i am more focused on efficiency as perpixel graphics is slow0
> [for example if you hold w you got wire-model
> and you see that it is slower than fill
> triangles.. would like to optimise it too,
> drawline code was on comp.lang.c
> 
> in general 
> mouse wheel up makes app fullscreen
> mouse wheel down makes pause releases the mouse arrow
> control + 3,4,5,6 changes the resolution
> pressing left shift + mouse makes strafe moves
> 
> ps to test better to run the last one prog, (here program24)
> 
> also to need build some simple models form tetrahedrons solid_model.txt is model file
> where you define tetrahedrons to build some simple model this way, i need to build some
> simple ship model from it
> 
> 
> 

ps i found something simple

From RGB to YIQ

y = r* 0.299 + g*  0.587 + b*  0.114 
i = r* 0.596 + g* -0.275 + b* -0.321 
q = r* 0.212 + g* -0.528 + b*  0.311

From YIQ to RGB

r = y* 1 + i*  0.956 + q*  0.620 
g = y* 1 + i* -0.272 + q* -0.647 
b = y* 1 + i* -1.108 + q*  1.705

y is said to be luma and I Q is mixed
chroma, maybe inc/dec of this luma will
give somewhat better result

it seems that it is worse than those Lab
or something but easier

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darkening colour fir <profesor.fir@gmail.com> - 2015-04-06 01:12 -0700
  Re: darkening colour "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> - 2015-04-06 10:52 +0200
    Re: darkening colour Bartc <bc@freeuk.com> - 2015-04-06 11:21 +0100
      Re: darkening colour "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> - 2015-04-06 12:44 +0200
        Re: darkening colour Bartc <bc@freeuk.com> - 2015-04-06 12:54 +0100
          Re: darkening colour "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> - 2015-04-06 14:27 +0200
          Re: darkening colour fir <profesor.fir@gmail.com> - 2015-04-06 05:51 -0700
    Re: darkening colour fir <profesor.fir@gmail.com> - 2015-04-06 04:38 -0700
      Re: darkening colour "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> - 2015-04-06 14:52 +0200
        Re: darkening colour fir <profesor.fir@gmail.com> - 2015-04-06 06:25 -0700
          Re: darkening colour "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> - 2015-04-06 17:02 +0200
            Re: darkening colour fir <profesor.fir@gmail.com> - 2015-04-06 09:36 -0700
              Re: darkening colour "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> - 2015-04-07 10:52 +0200
                Re: darkening colour fir <profesor.fir@gmail.com> - 2015-04-07 02:10 -0700
                Re: darkening colour "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> - 2015-04-07 11:30 +0200
                Re: darkening colour fir <profesor.fir@gmail.com> - 2015-04-07 03:24 -0700
                Re: darkening colour "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> - 2015-04-07 13:00 +0200
      Re: darkening colour Bartc <bc@freeuk.com> - 2015-04-06 14:17 +0100
        Re: darkening colour fir <profesor.fir@gmail.com> - 2015-04-06 06:27 -0700
          Re: darkening colour Bartc <bc@freeuk.com> - 2015-04-06 14:39 +0100
            Re: darkening colour fir <profesor.fir@gmail.com> - 2015-04-06 06:48 -0700
              Re: darkening colour Bartc <bc@freeuk.com> - 2015-04-06 16:02 +0100
                Re: darkening colour fir <profesor.fir@gmail.com> - 2015-04-06 09:44 -0700
                Re: darkening colour Bartc <bc@freeuk.com> - 2015-04-06 21:05 +0100
                Re: darkening colour fir <profesor.fir@gmail.com> - 2015-04-07 00:51 -0700
                Re: darkening colour fir <profesor.fir@gmail.com> - 2015-04-07 01:12 -0700

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