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From: Geoff Wedig
Subject: Proximity pattern in Normal?
Date: 12 Mar 2001 11:03:23
Message: <3aacf34b@news.povray.org>
I'm trying to use the proximity pattern in a normal.  However, MP0.7 is
telling me that it isn't finding a normal type.  I thought perhaps I needed
to add something like bozo, but if I do it before, it balks at the proximity
("no } found, found proximity instead").  If I do it after, it breaks the
other way.  It looks to me like the proximity pattern is recognized as a
pattern but isn't *set* as the pattern, so when it gets to the end of the
normal, it bombs.

Here is the normal I've been working with:

normal
{
  proximity
  {
    crater, 10
    samples 10
    sample_bailout 100
    max_density 1
    type 1
    sides 1
  }
  normal_map
  {
    [0 .5 ]
    [0.19 .5 ]
    [.2 1 ]
    [.3 .5 ]
    [1  .5 ]
  }
}    
}

Anyone got any ideas?

Geoff


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From: Chris Huff
Subject: Re: Proximity pattern in Normal?
Date: 12 Mar 2001 12:24:39
Message: <chrishuff-8D2C17.12203412032001@news.povray.org>
In article <3aacf34b@news.povray.org>, Geoff Wedig 
<wed### [at] darwinepbicwruedu> wrote:

> I'm trying to use the proximity pattern in a normal.  However, MP0.7 
> is telling me that it isn't finding a normal type.  I thought perhaps 
> I needed to add something like bozo, but if I do it before, it balks 
> at the proximity ("no } found, found proximity instead").  If I do it 
> after, it breaks the other way.  It looks to me like the proximity 
> pattern is recognized as a pattern but isn't *set* as the pattern, so 
> when it gets to the end of the normal, it bombs.

You were putting "bozo" alongside the proximity{} block? That won't 
work, you can only specify a single pattern for a normal. When it 
finishes parsing the first pattern and finds another one, of course it 
gives an error.
Did you try commenting out the proximity{} block and using only bozo or 
another pattern? I don't think the proximity pattern is the problem 
here...


>   normal_map
>   {
>     [0 .5 ]
>     [0.19 .5 ]
>     [.2 1 ]
>     [.3 .5 ]
>     [1  .5 ]
>   }

This isn't the syntax for normal_maps...you need to put a normal 
modifier in the entries, not a float value. I suspect you want a 
slope_map...but even then, this is the wrong syntax, slope_maps take 2D 
vectors.
Also, there is an extra "}" in the code you posted...but I assume that 
is just a cut-n-paste error.

-- 
Christopher James Huff
Personal: chr### [at] maccom, http://homepage.mac.com/chrishuff/
TAG: chr### [at] tagpovrayorg, http://tag.povray.org/

<><


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From: Geoff Wedig
Subject: Re: Proximity pattern in Normal?
Date: 12 Mar 2001 13:35:45
Message: <3aad1701@news.povray.org>
Chris Huff <chr### [at] maccom> wrote:

> In article <3aacf34b@news.povray.org>, Geoff Wedig 
> <wed### [at] darwinepbicwruedu> wrote:

>> I'm trying to use the proximity pattern in a normal.  However, MP0.7 
>> is telling me that it isn't finding a normal type.  I thought perhaps 
>> I needed to add something like bozo, but if I do it before, it balks 
>> at the proximity ("no } found, found proximity instead").  If I do it 
>> after, it breaks the other way.  It looks to me like the proximity 
>> pattern is recognized as a pattern but isn't *set* as the pattern, so 
>> when it gets to the end of the normal, it bombs.

> You were putting "bozo" alongside the proximity{} block? That won't 
> work, you can only specify a single pattern for a normal. When it 
> finishes parsing the first pattern and finds another one, of course it 
> gives an error.

I didn't think it would. I only added it because it kept saying "Normal type
not defined"

> Did you try commenting out the proximity{} block and using only bozo or 
> another pattern? I don't think the proximity pattern is the problem 
> here...
>>   normal_map
>>   {
>>     [0 .5 ]
>>     [0.19 .5 ]
>>     [.2 1 ]
>>     [.3 .5 ]
>>     [1  .5 ]
>>   }

> This isn't the syntax for normal_maps...you need to put a normal 
> modifier in the entries, not a float value. I suspect you want a 
> slope_map...but even then, this is the wrong syntax, slope_maps take 2D 
> vectors.

I know.  I was trying to take a pigment I made with a proximity and use it
in the normal instead.  I knew I'd have to jiggle the variables, but since
it didn't work at all...

In fact, this is the problem.  When I changed to a slope map, it worked. 
didn't do what I wanted, but it didn't crash. ;)

Thanks.

Geoff


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From: Chris Huff
Subject: Re: Proximity pattern in Normal?
Date: 12 Mar 2001 15:16:10
Message: <chrishuff-F09A95.15120512032001@news.povray.org>
In article <3aad1701@news.povray.org>, Geoff Wedig 
<wed### [at] darwinepbicwruedu> wrote:

> I didn't think it would. I only added it because it kept saying "Normal 
> type not defined"

Because you were specifying a float value when it expected a normal 
pattern or normal identifier.


> I know.  I was trying to take a pigment I made with a proximity and 
> use it in the normal instead.  I knew I'd have to jiggle the 
> variables, but since it didn't work at all...

Well, of course it didn't...you have to do more than "jiggle the 
variables", you have to use a completely different type. Don't expect to 
be able to use an object as a color, either.


> In fact, this is the problem.  When I changed to a slope map, it worked. 
> didn't do what I wanted,

I would be surprised if it did...you are still using the wrong type. The 
slope_map takes a 2D vector...when you specify a float, the same value 
is used for both components when it is automatically promoted to a 2D 
vector, for example, 0.5 is promoted to < 0.5, 0.5>...which is pretty 
much useless in slope_maps. The first component is "height", and the 
second is "slope". POV uses a spline based on this information to figure 
out the slope of the pattern at in-between values, and get an equivalent 
to a "color_map" for normals. A normal_map behaves more like a 
pigment_map than a color_map, it interpolates between complete normals, 
each with it's own pattern and other normal stuff.
If you stated what your goal is, you might better help...however, I 
suggest you look through the manual, which clearly explains the syntax 
of normals, normal_maps, and slope_maps...especially look at section 
2.7.2, which is a tutorial about normals, and section 4.7.2, which is a 
complete syntax reference for normals.


> but it didn't crash. ;)

Wait, it crashed before? That's not good, it means there is a bug 
somewhere...it should just stop parsing and produce an error message.

-- 
Christopher James Huff
Personal: chr### [at] maccom, http://homepage.mac.com/chrishuff/
TAG: chr### [at] tagpovrayorg, http://tag.povray.org/

<><


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From: Geoff Wedig
Subject: Re: Proximity pattern in Normal?
Date: 13 Mar 2001 07:36:55
Message: <3aae1467@news.povray.org>
Chris Huff <chr### [at] maccom> wrote:

> In article <3aad1701@news.povray.org>, Geoff Wedig 
> <wed### [at] darwinepbicwruedu> wrote:

>> I didn't think it would. I only added it because it kept saying "Normal 
>> type not defined"

> Because you were specifying a float value when it expected a normal 
> pattern or normal identifier.


>> I know.  I was trying to take a pigment I made with a proximity and 
>> use it in the normal instead.  I knew I'd have to jiggle the 
>> variables, but since it didn't work at all...

> Well, of course it didn't...you have to do more than "jiggle the 
> variables", you have to use a completely different type. Don't expect to 
> be able to use an object as a color, either.

It was a mistake on my part, because I (stupidly) assumed that a normal
takes a normal_map.  I don't know why I thought that, since a pigment
doesn't take a pigment_map, nor a texture a texture_map, but I did.  Mea
Culpa.


>> In fact, this is the problem.  When I changed to a slope map, it worked. 
>> didn't do what I wanted,

> I would be surprised if it did...you are still using the wrong type. The 
> slope_map takes a 2D vector...when you specify a float, the same value 
> is used for both components when it is automatically promoted to a 2D 
> vector, for example, 0.5 is promoted to < 0.5, 0.5>...which is pretty 
> much useless in slope_maps.

No, when I changed to slope map, I changed the components too.  I know that
the type would be upgraded, and at least I'd be able to see the areas where
things were happening, and could tweak later, but I didn't do that.

 The first component is "height", and the 
> second is "slope". POV uses a spline based on this information to figure 
> out the slope of the pattern at in-between values, and get an equivalent 
> to a "color_map" for normals. A normal_map behaves more like a 
> pigment_map than a color_map, it interpolates between complete normals, 
> each with it's own pattern and other normal stuff.
> If you stated what your goal is, you might better help...however, I 
> suggest you look through the manual, which clearly explains the syntax 
> of normals, normal_maps, and slope_maps...especially look at section 
> 2.7.2, which is a tutorial about normals, and section 4.7.2, which is a 
> complete syntax reference for normals.

I'm pretty familiar with this stuff, really.  I just had a brain loss for a
bit there.  Sometimes the simplest things seem to disappear.

As I see it, the error should have come up in the normal_map, though, not at
the end of the normal.  That's where there were missing types, it seems,
since a normal can consist of a normal_map of normals.  It was specified
correctly, but the normal_map wasn't.  Again, it was a stupid error, but the
error message was a little esoteric.

>> but it didn't crash. ;)

> Wait, it crashed before? That's not good, it means there is a bug 
> somewhere...it should just stop parsing and produce an error message.

Sorry again.  Crashed in the euphamistic sense of "didn't draw a picture of
stunning complexity and beauty."  Of course, by that definition, POVray
always crashes for me. :/

Geoff


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From: Chris Huff
Subject: Re: Proximity pattern in Normal?
Date: 13 Mar 2001 12:57:36
Message: <chrishuff-D88E0B.12531113032001@news.povray.org>
In article <3aae1467@news.povray.org>, Geoff Wedig 
<wed### [at] darwinepbicwruedu> wrote:

> It was a mistake on my part, because I (stupidly) assumed that a normal
> takes a normal_map.  I don't know why I thought that, since a pigment
> doesn't take a pigment_map, nor a texture a texture_map, but I did.

Um, a normal *can* take a normal_map. A pigment can take a pigment_map, 
and a texture can take a texture_map. No finish_map, though...
And their syntaxes are all consistent...a normal_map takes normal stuff, 
a pigment_map takes pigment stuff, and a texture_map takes texture stuff.
The slope_map is just more like a color_map than a pigment_map, it 
interpolates between slopes, not normals, like the color_map 
interpolates between colors instead of pigments.

-- 
Christopher James Huff
Personal: chr### [at] maccom, http://homepage.mac.com/chrishuff/
TAG: chr### [at] tagpovrayorg, http://tag.povray.org/

<><


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From: Geoff Wedig
Subject: Re: Proximity pattern in Normal?
Date: 13 Mar 2001 13:42:03
Message: <3aae69fb@news.povray.org>
Chris Huff <chr### [at] maccom> wrote:

> In article <3aae1467@news.povray.org>, Geoff Wedig 
> <wed### [at] darwinepbicwruedu> wrote:

>> It was a mistake on my part, because I (stupidly) assumed that a normal
>> takes a normal_map.  I don't know why I thought that, since a pigment
>> doesn't take a pigment_map, nor a texture a texture_map, but I did.

> Um, a normal *can* take a normal_map. A pigment can take a pigment_map, 
> and a texture can take a texture_map. No finish_map, though...
> And their syntaxes are all consistent...a normal_map takes normal stuff, 
> a pigment_map takes pigment stuff, and a texture_map takes texture stuff.
> The slope_map is just more like a color_map than a pigment_map, it 
> interpolates between slopes, not normals, like the color_map 
> interpolates between colors instead of pigments.

Right.  So the only thing I'm wondering is, why was the error being reported
in the external normal rather than the internal one?

Geoff


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From: Chris Huff
Subject: Re: Proximity pattern in Normal?
Date: 13 Mar 2001 14:11:10
Message: <chrishuff-F05442.14064513032001@news.povray.org>
In article <3aae69fb@news.povray.org>, Geoff Wedig 
<wed### [at] darwinepbicwruedu> wrote:

> Right.  So the only thing I'm wondering is, why was the error being 
> reported in the external normal rather than the internal one?

I have no idea...but I've heard about this kind of thing happening 
before.

-- 
Christopher James Huff
Personal: chr### [at] maccom, http://homepage.mac.com/chrishuff/
TAG: chr### [at] tagpovrayorg, http://tag.povray.org/

<><


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