clipka <ano### [at] anonymousorg> wrote:>
> The whole reason for this effect is that the camera must shoot its rays
> from /somewhere/ - infinity won't work, as it's not a good value to do
> math on ;-). So the rays are shot from the plane going through the
> camera position and being perpendicular to the camera direction. If one
> of your figures sticks its head through this plane, the camera rays will
> hit (and thus see) only his inside, effectively decapitating him.

Thanks for the articulate explanation.  I still think the diagrams in the povray
camera docs drive me crazy: when I eventually figure out how to do some new
trick, it seems it was after I left a blind alley I was led to from my
presumptions about the picture of the angles, etc.

Anyway, this was an idea I saw at StackOverflow for sprites.  And this is the
one case where povray knocks all other apps flat for being able to make a bunch
of sprites at once.

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clipka <ano### [at] anonymousorg> wrote:
> Am 12.12.2012 14:56, schrieb gregjohn:
> > Hi. I was starting to experiment with the use of povray to make a single-image
> > sprite sheet.  It would of course be useful to make it using an orthographic
> > camera.  But my figures are getting cut off.   Is there a way around this?
> > TIA.
>
> Move the camera further away, maybe?

Moving away an orthographic camera? What should be achieved from this?

Best regards,
michael

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"gregjohn" <pte### [at] yahoocom> wrote:
> clipka <ano### [at] anonymousorg> wrote:>
> > The whole reason for this effect is that the camera must shoot its rays
> > from /somewhere/ - infinity won't work, as it's not a good value to do
> > math on ;-). So the rays are shot from the plane going through the
> > camera position and being perpendicular to the camera direction. If one
> > of your figures sticks its head through this plane, the camera rays will
> > hit (and thus see) only his inside, effectively decapitating him.
>
> Thanks for the articulate explanation.  I still think the diagrams in the povray
> camera docs drive me crazy: when I eventually figure out how to do some new
> trick, it seems it was after I left a blind alley I was led to from my
> presumptions about the picture of the angles, etc.
>
> Anyway, this was an idea I saw at StackOverflow for sprites.  And this is the
> one case where povray knocks all other apps flat for being able to make a bunch
> of sprites at once.

Moving away an orthographic camera usually yields nothing since the camera is
orthographic.
That is the nature of an orthographic camera.
You must fit your scene into the orthographic view.

Best regards,
michael

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Am 15.12.2012 20:51, schrieb MichaelJF:
> clipka <ano### [at] anonymousorg> wrote:
>> Am 12.12.2012 14:56, schrieb gregjohn:
>>> Hi. I was starting to experiment with the use of povray to make a single-image
>>> sprite sheet.  It would of course be useful to make it using an orthographic
>>> camera.  But my figures are getting cut off.   Is there a way around this?
>>> TIA.
>>
>> Move the camera further away, maybe?
>
> Moving away an orthographic camera? What should be achieved from this?

Making the figures not getting cut off.

Even in an orthographic render, the camera position determines what you 
see: Everything "in front" of the camera is visible, everything "behind" 
is not.

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clipka <ano### [at] anonymousorg> wrote:
> Am 15.12.2012 20:51, schrieb MichaelJF:
> > clipka <ano### [at] anonymousorg> wrote:
> >> Am 12.12.2012 14:56, schrieb gregjohn:
> >>> Hi. I was starting to experiment with the use of povray to make a single-image
> >>> sprite sheet.  It would of course be useful to make it using an orthographic
> >>> camera.  But my figures are getting cut off.   Is there a way around this?
> >>> TIA.
> >>
> >> Move the camera further away, maybe?
> >
> > Moving away an orthographic camera? What should be achieved from this?
>
> Making the figures not getting cut off.
>
> Even in an orthographic render, the cameria position determines what you
> see: Everything "in front" of the camera is viwithsible, everiything "behind"
> is not.

With the orthographic camera the up and right vectors determines the visible
scene and nott
the distance of the camera  to the desired objects. As far as i experienced.

Best regards,
michael

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Le 15/12/2012 22:12, MichaelJF nous fit lire :
> clipka <ano### [at] anonymousorg> wrote:
>> Am 15.12.2012 20:51, schrieb MichaelJF:
>>> clipka <ano### [at] anonymousorg> wrote:
>>>> Am 12.12.2012 14:56, schrieb gregjohn:
>>>>> Hi. I was starting to experiment with the use of povray to make a single-image
>>>>> sprite sheet.  It would of course be useful to make it using an orthographic
>>>>> camera.  But my figures are getting cut off.   Is there a way around this?
>>>>> TIA.
>>>>
>>>> Move the camera further away, maybe?
>>>
>>> Moving away an orthographic camera? What should be achieved from this?
>>
>> Making the figures not getting cut off.
>>
>> Even in an orthographic render, the cameria position determines what you
>> see: Everything "in front" of the camera is viwithsible, everiything "behind"
>> is not.
> 
> With the orthographic camera the up and right vectors determines the visible
> scene and nott
> the distance of the camera  to the desired objects. As far as i experienced.

Yet, if an object is behind the camera rectangular-plane (for
orthographic, it's not a point-camera), it is not on the picture.

The length of direction's vector is irrelevant (as long as not 0), yet
the orthographic camera has no eye on the back of its head.

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May I say that this whole thread supports my claim that the camera docs, notably
the diagram, don't explain what it the orthographic camera does?  I presume
everyone posting in this thread has in fact RTFM.

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Am 17.12.2012 13:54, schrieb gregjohn:
> May I say that this whole thread supports my claim that the camera docs, notably
> the diagram, don't explain what it the orthographic camera does?  I presume
> everyone posting in this thread has in fact RTFM.

The diagram indeed only explains the standard perspective camera.

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clipka <ano### [at] anonymousorg> wrote:
> Am 17.12.2012 13:54, schrieb gregjohn:
> > May I say that this whole thread supports my claim that the camera docs, notably
> > the diagram, don't explain what it the orthographic camera does?  I presume
> > everyone posting in this thread has in fact RTFM.
>
> The diagram indeed only explains the standard perspective camera.

Okay, so the community (if not me) should cough up a diagram that explains
exactly what orthographic is up to.

But even the standard camera doc/diagram piles on both critically needed
parameters, and I-guess-if-you-need-to-specify-it-that-way parameters, without
explaining how the redundant ones interact with the critical ones or which order
is critical,   into one big pile.
up / right/ angle/ position/ look_at, etc.

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On 12/17/2012 10:23 AM, gregjohn wrote:
> clipka <ano### [at] anonymousorg> wrote:
>> Am 17.12.2012 13:54, schrieb gregjohn:
>>> May I say that this whole thread supports my claim that the camera docs, notably
>>> the diagram, don't explain what it the orthographic camera does?  I presume
>>> everyone posting in this thread has in fact RTFM.
>>
>> The diagram indeed only explains the standard perspective camera.
>
> Okay, so the community (if not me) should cough up a diagram that explains
> exactly what orthographic is up to.
>
> But even the standard camera doc/diagram piles on both critically needed
> parameters, and I-guess-if-you-need-to-specify-it-that-way parameters, without
> explaining how the redundant ones interact with the critical ones or which order
> is critical,   into one big pile.
> up / right/ angle/ position/ look_at, etc.

You guys come up with something and I'll make sure it finds it's way 
into the docs ...

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