POV-Ray : Newsgroups : povray.competition : Re: Detail Image Server Time: 29 Sep 2020 19:02:38 GMT
  Re: Detail Image (Message 1 to 4 of 4)  
From: jute
Subject: Re: Detail Image
Date: 11 Oct 2004 13:05:00
Message: <web.416a80fcf8f8ca6167c1c3ff0@news.povray.org>
Oleguer wrote:
> Yes, Ok I had read this web page. Now I used this code "+SR0.44 +ER0.61
> +SC0.58 +EC0.75". The main picture is in 1280x960.
> 1280/25= 51'2 and 960/25= 38'4.
> How can I now if my square is 51'2 width and 38'4 height? Because I supose
> that if the square is biger than 51'1x38'4 I can't upload it.
>
> How do you know the other number that appear on the exemple? ( +EC0.640625
> and +ER0.455469).

You're required to render 1/25 of the area of your original image;
that means that the difference between your +sc/+ec and +sr/+er has to
be less than, or equal to, 0.2.  That 0.2 is simply 1/5, which in turn
stems from the 1/25 area requirement: 1/5*1/5 for the width and height
respectively gives you an area that is 1/25 of the original).  That's
where the other numbers come from.

Hint: you can 'try out' your detail view by creating in your image
editor a movable square (or a crop window) with size 256x192.
Anything you see of your main image _through this rectangle_ is
suitable (once rendered at proper resolution) as your detail image(s).

Please notice that your 1280/25 calculation is kind of "wrong" (it
would give you an area that is 625th of the main image, which is 25
times smaller than required; it's OK by the rules, but it seems to me
that this is not what you're attempting! :))

The +sc/+ec/+sr/+er you give yield:
ec - sc = 0.75 - 0.58 = 0.17, which is less than 0.2, therefore ok.
er - sr = 0.61 - 0.44 = 0.17, which is less than 0.2, therefore ok.
This would give you a detail image whose area is 0.17*0.17 = 0.0289 < 0.04,
so everything's fine!  (0.04 = 1/25)

To render the detail view with POV-Ray you would say

+sc0.58 +ec0.75 +sr0.44 +er0.61 +w6400 +h4800

and the resulting detail image would have pixel dimensions 1088x816
after the margins are cropped out, which is just enough as required by
the rules ("The detail views have to be at least 800 pixels wide and
high").  Notice that you'd probably want to have +a on too, because
you're not going to scale this image down.

It seems to me you have actually done all of this, or at least
considered it, so are you still having a problem?  If you're seeing
the details you WANT in your detail images, and haven't made a typo in
posting your parameters, then everything should be OK.

DON'T LET ME GET YOU CONFUSED NOW!  You're doing fine, here's just how
you would render the same detail image in 1280x960.

1280/0.17 = 7529,411
960/0.17 = 5647,059
--> +sc0.58 +ec0.75 +sr0.44 +er0.61 +w7530 +h5648

--
jussi.kantola
From: Oleguer Vilella
Subject: Re: Detail Image
Date: 11 Oct 2004 18:48:37
Message: <416ad585$1@news.povray.org>
Yes Ok, no confused. Many thanks for your help. Yes I was thinking that I
was doing the square right.
But, to calculate the pixel co-ordinates from the relative co-ordinates,
Thorsten said that I have to multiply 1280*0.44=563 (+sc0.58 +ec0.75 +sr0.44
+er0.61 +w6400 +h4800). Well, now is it right?:

1280*0.44= 563'2 // X-Position (Horizontal)
1280*0.75= 960 // Y-Position (Vertical)
960*0.61= 585'6 // X-Position (Horizontal)
960*0.58= 556'8 // Y-Position (Vertical)

Best regards,
Oleguer





"jute" <nomail@nomail> escribió en el mensaje
news:web.416a80fcf8f8ca6167c1c3ff0@news.povray.org...
> Oleguer wrote:
> > Yes, Ok I had read this web page. Now I used this code "+SR0.44 +ER0.61
> > +SC0.58 +EC0.75". The main picture is in 1280x960.
> > 1280/25= 51'2 and 960/25= 38'4.
> > How can I now if my square is 51'2 width and 38'4 height? Because I
supose
> > that if the square is biger than 51'1x38'4 I can't upload it.
> >
> > How do you know the other number that appear on the exemple? (
+EC0.640625
> > and +ER0.455469).
>
> You're required to render 1/25 of the area of your original image;
> that means that the difference between your +sc/+ec and +sr/+er has to
> be less than, or equal to, 0.2.  That 0.2 is simply 1/5, which in turn
> stems from the 1/25 area requirement: 1/5*1/5 for the width and height
> respectively gives you an area that is 1/25 of the original).  That's
> where the other numbers come from.
>
> Hint: you can 'try out' your detail view by creating in your image
> editor a movable square (or a crop window) with size 256x192.
> Anything you see of your main image _through this rectangle_ is
> suitable (once rendered at proper resolution) as your detail image(s).
>
> Please notice that your 1280/25 calculation is kind of "wrong" (it
> would give you an area that is 625th of the main image, which is 25
> times smaller than required; it's OK by the rules, but it seems to me
> that this is not what you're attempting! :))
>
> The +sc/+ec/+sr/+er you give yield:
> ec - sc = 0.75 - 0.58 = 0.17, which is less than 0.2, therefore ok.
> er - sr = 0.61 - 0.44 = 0.17, which is less than 0.2, therefore ok.
> This would give you a detail image whose area is 0.17*0.17 = 0.0289 <
0.04,
> so everything's fine!  (0.04 = 1/25)
>
> To render the detail view with POV-Ray you would say
>
> +sc0.58 +ec0.75 +sr0.44 +er0.61 +w6400 +h4800
>
> and the resulting detail image would have pixel dimensions 1088x816
> after the margins are cropped out, which is just enough as required by
> the rules ("The detail views have to be at least 800 pixels wide and
> high").  Notice that you'd probably want to have +a on too, because
> you're not going to scale this image down.
>
> It seems to me you have actually done all of this, or at least
> considered it, so are you still having a problem?  If you're seeing
> the details you WANT in your detail images, and haven't made a typo in
> posting your parameters, then everything should be OK.
>
> DON'T LET ME GET YOU CONFUSED NOW!  You're doing fine, here's just how
> you would render the same detail image in 1280x960.
>
> 1280/0.17 = 7529,411
> 960/0.17 = 5647,059
> --> +sc0.58 +ec0.75 +sr0.44 +er0.61 +w7530 +h5648
>
> --
> jussi.kantola
>
>
From: Thorsten Froehlich
Subject: Re: Detail Image
Date: 11 Oct 2004 19:28:15
Message: <416adecf@news.povray.org>
In article <416ad585$1@news.povray.org> , "Oleguer Vilella" 
<ole### [at] infonegociocom> wrote:

> Well, now is it right?:
>
> 1280*0.44= 563'2 // X-Position (Horizontal)
> 1280*0.75= 960 // Y-Position (Vertical)
> 960*0.61= 585'6 // X-Position (Horizontal)
> 960*0.58= 556'8 // Y-Position (Vertical)

No, you mess up all values:

1280 * 0.58 = X-Position
960 * 0.44 = Y-Position

1280 * 0.75 = X-Position
960 * 0.61 = Y-Position

because

+sc is the start column, +ec the end column, +sr the start row and +er the
end row.  A column extends along the vertical (Y) axis, a row extends along
the horizontal (X) axis.

    Thorsten

____________________________________________________
Thorsten Froehlich, Duisburg, Germany
e-mail: tho### [at] trfde

Visit POV-Ray on the web: http://mac.povray.org
From: Oleguer Vilella
Subject: Re: Detail Image
Date: 11 Oct 2004 19:32:32
Message: <416adfd0$1@news.povray.org>
Ah, yes ok. Sorry for the stupid question Thorsten.

Best regards,
Oleguer


"Thorsten Froehlich" <tho### [at] trfde> escribió en el mensaje
news:416adecf@news.povray.org...
> In article <416ad585$1@news.povray.org> , "Oleguer Vilella"
> <ole### [at] infonegociocom> wrote:
>
> > Well, now is it right?:
> >
> > 1280*0.44= 563'2 // X-Position (Horizontal)
> > 1280*0.75= 960 // Y-Position (Vertical)
> > 960*0.61= 585'6 // X-Position (Horizontal)
> > 960*0.58= 556'8 // Y-Position (Vertical)
>
> No, you mess up all values:
>
> 1280 * 0.58 = X-Position
> 960 * 0.44 = Y-Position
>
> 1280 * 0.75 = X-Position
> 960 * 0.61 = Y-Position
>
> because
>
> +sc is the start column, +ec the end column, +sr the start row and +er the
> end row.  A column extends along the vertical (Y) axis, a row extends
along
> the horizontal (X) axis.
>
>     Thorsten
>
> ____________________________________________________
> Thorsten Froehlich, Duisburg, Germany
> e-mail: tho### [at] trfde
>
> Visit POV-Ray on the web: http://mac.povray.org

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