POV-Ray : Newsgroups : povray.general : Start_column, end column, etc. Server Time
7 Nov 2024 11:34:33 EST (-0500)
  Start_column, end column, etc. (Message 1 to 7 of 7)  
From: Tom A 
Subject: Start_column, end column, etc.
Date: 13 Mar 2002 12:08:17
Message: <3C8F877F.46AA455C@my-deja.com>
Hi. 

I rendered a picture (in windows POV) at 800x600.  I then used the
preview to find a subset of the picture I want to animate.  I set up the
start_column, end_column, start_row, end_row fine.  But the subset is
rendering in the middle of an 800x600 black picture.  

Is there any easy way to get it to produce just the part of the picture
I'm interested in?

I eventually want to write a program that will display the animation
over the correct part of the picture, so for efficiency, I'll want the
animation as small as possible.

If there is no way, I'll write a program to extract the important part
out of the various frames, but I'd rather not have to do that.

Thanks!

-- 
Tom A.
"No doubt many that post deserve to be flamed.  And many that are flamed
didn't deserve it.  Can you give them the latter?  Then don't be so
quick to deal out the former!" - not Gandalf.
Deja mail is gone.  Look for me at raugost at yahoo . com


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From: Hermann Voßeler
Subject: Re: Start_column, end column, etc.
Date: 13 Mar 2002 12:58:31
Message: <3C8F9144.40700@webcon.de>
Tom A. wrote:
> I rendered a picture (in windows POV) at 800x600.  I then used the
> preview to find a subset of the picture I want to animate.  I set up the
> start_column, end_column, start_row, end_row fine.  But the subset is
> rendering in the middle of an 800x600 black picture.  
> 
> Is there any easy way to get it to produce just the part of the picture
> I'm interested in?
> 
IIRC, there is no "easy" way, without doing vector math with
the camera vectors. Maybe someone wrote a macro for this?

Is your subset symmetrical to the middle of the image?
Then you could try to play with the "direction" vector
(make it longer to get smaller region) or with the "angle"
keyword.

Hermann Vosseler


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From:
Subject: Re: Start_column, end column, etc.
Date: 13 Mar 2002 13:08:35
Message: <ca5v8usa0f7as3799nafeu62lhmbf596pd@4ax.com>
On Wed, 13 Mar 2002 11:08:15 -0600, "Tom A." <tar### [at] my-dejacom> wrote:
> I rendered a picture (in windows POV) at 800x600.  I then used the
> preview to find a subset of the picture I want to animate.  I set up the
> start_column, end_column, start_row, end_row fine.  But the subset is
> rendering in the middle of an 800x600 black picture. 

Have you compared preview window with image written to file ?
IIRC it contains only subset. At least last time when I used subset of rows it
worked this way.

> I eventually want to write a program that will display the animation
> over the correct part of the picture, so for efficiency, I'll want the
> animation as small as possible.

But any compressed format of animation like gif, fli/flc, avi, mpg, asf
animate only part with changes. So animation encoder/player should worry about
it instead of you.

> If there is no way, I'll write a program to extract the important part
> out of the various frames, but I'd rather not have to do that.

Consider asking in animation group.

ABX
--
disc{z,-z 5#macro O()asc(substr("-+((1*(,1,/.-,*/(,&.323/'1"e,1))*.1-4#declare
e=e-1;#end#local e=26;pigment{#local g=function(_){ceil(_)-_}function#local//X
k=function{pattern{object{sphere_sweep{linear_spline 13#while(e>0)<O(),O()//AB
>.01#end}}}}{k(g(atan2(x,y)),g(ln((y+x)^2+1e-5)),0)}}finish{ambient 1}}//POV35


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From: Tom A 
Subject: Re: Start_column, end column, etc.
Date: 14 Mar 2002 10:13:04
Message: <3C90BDFF.6A9A32A1@my-deja.com>

> 
> On Wed, 13 Mar 2002 11:08:15 -0600, "Tom A." <tar### [at] my-dejacom> wrote:
> > I rendered a picture (in windows POV) at 800x600.  I then used the
> > preview to find a subset of the picture I want to animate.  I set up the
> > start_column, end_column, start_row, end_row fine.  But the subset is
> > rendering in the middle of an 800x600 black picture.
> 
> Have you compared preview window with image written to file ?
> IIRC it contains only subset. At least last time when I used subset of rows it
> worked this way.

The file generated is much smaller than the original picture (this could
be from run length encoding the black space, though). 

However, I was completely unable to look at the generated files: I tried
two viewers and both said the TARGA files were unreadable.  I'll retry
with BMP.

> 
> > I eventually want to write a program that will display the animation
> > over the correct part of the picture, so for efficiency, I'll want the
> > animation as small as possible.
> 
> But any compressed format of animation like gif, fli/flc, avi, mpg, asf
> animate only part with changes. So animation encoder/player should worry about
> it instead of you.

As long as it knows that "black" is invisible.
 
> > If there is no way, I'll write a program to extract the important part
> > out of the various frames, but I'd rather not have to do that.
> 
> Consider asking in animation group.

Thanks.
 
> ABX
> --

-- 
Tom A.
"No doubt many that post deserve to be flamed.  And many that are flamed
didn't deserve it.  Can you give them the latter?  Then don't be so
quick to deal out the former!" - not Gandalf.
Deja mail is gone.  Look for me at raugost at yahoo . com


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From:
Subject: Re: Start_column, end column, etc.
Date: 14 Mar 2002 10:20:30
Message: <cpf19usen6alhad8uuk2h9emhmmgg9klkc@4ax.com>
On Thu, 14 Mar 2002 09:13:03 -0600, "Tom A." <tar### [at] my-dejacom> wrote:
> I was completely unable to look at the generated files: I tried
> two viewers and both said the TARGA files were unreadable.

Try IrfanView - works fine with incomplete pictures.

> > But any compressed format of animation like gif, fli/flc, avi, mpg, asf
> > animate only part with changes. So animation encoder/player should worry about
> > it instead of you.
>
> As long as it knows that "black" is invisible.

Render whole picture then.

ABX


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From: Tom A 
Subject: Re: Start_column, end column, etc.
Date: 14 Mar 2002 12:17:33
Message: <3C90DB2D.D78B048C@my-deja.com>

> 
> On Thu, 14 Mar 2002 09:13:03 -0600, "Tom A." <tar### [at] my-dejacom> wrote:
> > I was completely unable to look at the generated files: I tried
> > two viewers and both said the TARGA files were unreadable.
> 
> Try IrfanView - works fine with incomplete pictures.

That was one of the viewers I used.
> 
> > > But any compressed format of animation like gif, fli/flc, avi, mpg, asf
> > > animate only part with changes. So animation encoder/player should worry about
> > > it instead of you.
> >
> > As long as it knows that "black" is invisible.
> 
> Render whole picture then.
> 
> ABX

-- 
Tom A.
"No doubt many that post deserve to be flamed.  And many that are flamed
didn't deserve it.  Can you give them the latter?  Then don't be so
quick to deal out the former!" - not Gandalf.
Deja mail is gone.  Look for me at raugost at yahoo . com


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From:
Subject: Re: Start_column, end column, etc.
Date: 14 Mar 2002 12:20:39
Message: <jsm19uoj6c61t62mtckl7f4kbvpmhrshvg@4ax.com>
On Thu, 14 Mar 2002 11:17:33 -0600, "Tom A." <tar### [at] my-dejacom> wrote:
> > Try IrfanView - works fine with incomplete pictures.
>
> That was one of the viewers I used.

So try the same with PNG. It worked for me with PNG.

ABX


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