Wlodzimierz ABX Skiba <abx### [at] abxartpl> wrote:
: did you consider my proposition to put tesselation as part of object modifiers ?

  I think that would be more difficult than it may sound.
  When povray parses an object, it creates internally an object of that
type. A tesselation modifier would have to change that object to a mesh
object.
  I'm not sure if there is any advantage in this either.

-- 
char*i="b[7FK@`3NB6>B:b3O6>:B:b3O6><`3:;8:6f733:>::b?7B>:>^B>C73;S1";
main(_,c,m){for(m=32;c=*i++-49;c&m?puts(""):m)for(_=(
c/4)&7;putchar(m),_--?m:(_=(1<<(c&3))-1,(m^=3)&3););}    /*- Warp -*/

Post a reply to this message

Nicolas Calimet <pov### [at] freefr> wrote:
: 	Can you tesselate a mesh object ?

  The patch can tesselate any solid object with a finite bounding box.
  If you want to tesselate a mesh, you'll have to make it solid (with
the inside_vector feature). I haven't tested it, but it should work
(as long as the solid mesh patch works).

-- 
char*i="b[7FK@`3NB6>B:b3O6>:B:b3O6><`3:;8:6f733:>::b?7B>:>^B>C73;S1";
main(_,c,m){for(m=32;c=*i++-49;c&m?puts(""):m)for(_=(
c/4)&7;putchar(m),_--?m:(_=(1<<(c&3))-1,(m^=3)&3););}    /*- Warp -*/

Post a reply to this message

ough, I don't like write explanations becouse my vocabulary appears poor :-(

Warp wrote in message <3a65c258@news.povray.org>...
>Wlodzimierz ABX Skiba <abx### [at] abxartpl> wrote:
>: did you consider my proposition to put tesselation as part of object
modifiers ?
>
>  I think that would be more difficult than it may sound.

I did it for my deform patch
Everything what it need is to change parse_object_mod to return (OBJECT *)
and change Parse_*() functions.

> When povray parses an object, it creates internally an object of that
> type. A tesselation modifier would have to change that object to a mesh
> object.

when you tesselate object you do it probably to use it insted of original object
for user there could be no difference - only speed up

>  I'm not sure if there is any advantage in this either.


I know that some peoples don't like such word like "modeller" according to
POV-script
but in modellers there is taskbar with operations applied to object and
rotation, scale and other linear operations are neighbours for twisting,
bending, screwing and neighbours for smoothing by removing of vertex, incresing
amount of vertex and something.

I you have ready function Parse_Tesselation() I can try simple apply to my
modified source of deform patch to apply your syntax and my proposed syntax.

hmm, I don't think that I explained :-(

ABX

Post a reply to this message

Wlodzimierz ABX Skiba wrote:
> 
> ough, I don't like write explanations becouse my vocabulary appears poor :-(
> 
> Warp wrote in message <3a65c258@news.povray.org>...
> >Wlodzimierz ABX Skiba <abx### [at] abxartpl> wrote:
> >: did you consider my proposition to put tesselation as part of object
> modifiers ?
> >
> >  I think that would be more difficult than it may sound.
> 
> I did it for my deform patch
> Everything what it need is to change parse_object_mod to return (OBJECT *)

That modification would be easy, maybe...

> and change Parse_*() functions.

But not that one : do you have an idea of the number of functions 
to patch ?

Moreover I found it counter-productive and dangerous:
 let's say we have a CSG operation (not a union) and
 you modify ONE of the component to tesselate while the
 other components remained unchanged.
 I'm not sure the CSG would still be possible.
 As a basic-final-user, I cannot understand why modifying a tiny attribute of
 a sphere/superellipsoid/cone/cylinder/box/whatever in a CSG construct 
 make a script failure...

Sincerely, I just like the way the tesselation object was introduced:
 it is a new object. dot. 
 Trying to be able to have the mesh object able to include it in
 its definition may or not be a good thing, I do not know.


> 
> > When povray parses an object, it creates internally an object of that
> > type. A tesselation modifier would have to change that object to a mesh
> > object.
> 
> when you tesselate object you do it probably to use it insted of original object
> for user there could be no difference - only speed up

No, at least for me: tesselation would also provide a different aspect
 (the 'polygon'/facet aspect), and that's also interesting.
 (instead of playing with the normal vector with a complex pattern)


> 
> >  I'm not sure if there is any advantage in this either.
> 
> I know that some peoples don't like such word like "modeller" according to
> POV-script
> but in modellers there is taskbar with operations applied to object and
> rotation, scale and other linear operations are neighbours for 

Yes the classical mods,

> twisting,
> bending, screwing 

This is the 'classical' problem with the POV approach: the intersection
of an object with a curved ray...

The 'twist/bend/screw' cannot be applied to all objects, but you
could make them to be some new 'object' (?) that would take a 
mesh-like object and some parameters:

 twist { object {my_mesh}, <center.x,center.y,center.z>,<axis.x,axis.y,axis.z>,
angle... }
 bend { object {my_mesh}, <center.x,center.y,center.z>,...}
 screw { object {my_mesh}, <center.x,center.y,center.z>,<axis.x,axis.y,axis.z>,
pitch... } 

Then when parsing, your 'object' is twisted/bent/screwed by 'simply' applying
a blind transformation to each vertex of the mesh

(beware: you not only have to transform the position of the vertex, but also
the normal... so the 'simply' is an overstatement).

>and neighbours for smoothing by removing of vertex, incresing
> amount of vertex and something.

That should be easy with the parameter of tesselation.

Post a reply to this message

> > and change Parse_*() functions.
>
> But not that one : do you have an idea of the number of functions
> to patch ?

everyone which calls parse_object_mods()
or I don't understand question
as I said I did it for source of megapov 0.6
and it took about 1 hour and it works

> Moreover I found it counter-productive and dangerous:
> let's say we have a CSG operation (not a union) and
> you modify ONE of the component to tesselate while the
> other components remained unchanged.
> I'm not sure the CSG would still be possible.

sometimes when you translate/rotate/scale component of CSG
rest of CSG dissapeare

> Sincerely, I just like the way the tesselation object was introduced:
> it is a new object. dot.

if you have large definition of object you must
jump over source to tesselate it : "tesselation {" at beginning and "}" at end
when you put this as object modifier you must type only in one place.

But consider that I'm talking about ideal tesselation with inheritance of
parameters such no_image, texture, hollow etc. from base object.

> > > When povray parses an object, it creates internally an object of that
> > > type. A tesselation modifier would have to change that object to a mesh
> > > object.
> >
> > when you tesselate object you do it probably to use it insted of original
object
> > for user there could be no difference - only speed up
>
> No, at least for me: tesselation would also provide a different aspect
>  (the 'polygon'/facet aspect), and that's also interesting.
>  (instead of playing with the normal vector with a complex pattern)

but you still can do it with tesselation as part of object modifiers, just with
this

#declare Object=csg{}
object{ Object }
object{ Object translate x*10 tesselate { 10, 7, 11 ... } }

> > >  I'm not sure if there is any advantage in this either.
> >
> > I know that some peoples don't like such word like "modeller" according to
> > POV-script
> > but in modellers there is taskbar with operations applied to object and
> > rotation, scale and other linear operations are neighbours for
>
> Yes the classical mods,
>
> > twisting,
> > bending, screwing
>
> This is the 'classical' problem with the POV approach: the intersection
> of an object with a curved ray...

But I've resolved this in my putch a little :-)

> The 'twist/bend/screw' cannot be applied to all objects, but you
> could make them to be some new 'object' (?) that would take a
> mesh-like object and some parameters:

What you mean by "cannot" ?
In my patch they can.

> twist { object {my_mesh}, <center.x,center.y,center.z>,<axis.x,axis.y,axis.z>,
>angle... }
> bend { object {my_mesh}, <center.x,center.y,center.z>,...}
> screw { object {my_mesh}, <center.x,center.y,center.z>,<axis.x,axis.y,axis.z>,
> pitch... }
>
> Then when parsing, your 'object' is twisted/bent/screwed by 'simply' applying
> a blind transformation to each vertex of the mesh

This cause a lot of new types of objects.
All this stuff shuld be IMO in object modifiers.

> (beware: you not only have to transform the position of the vertex, but also
> the normal... so the 'simply' is an overstatement).

perhaps you missed some images in p.b.i
just look at topics with word "deform" sended by me


when I twist box, my eyes see twisted box, not another type of object
even if it is triangulated

ABX

Post a reply to this message

Wlodzimierz ABX Skiba wrote:
> 


> > Moreover I found it counter-productive and dangerous:
> > let's say we have a CSG operation (not a union) and
> > you modify ONE of the component to tesselate while the
> > other components remained unchanged.
> > I'm not sure the CSG would still be possible.
> 
> sometimes when you translate/rotate/scale component of CSG
> rest of CSG dissapeare
> 

This may be a bug (unless the intersection/difference leave nothing,
in such case I would considere that it is normal).
But I do not think it may be a reason for the tesselation as
an object modifier.


> > Sincerely, I just like the way the tesselation object was introduced:
> > it is a new object. dot.
> 
> if you have large definition of object you must
> jump over source to tesselate it : "tesselation {" at beginning and "}" at end
> when you put this as object modifier you must type only in one place.
> 

This is only a problem for the editor.
And you may as well have a single line
#local to_be_tessalated = <<your big construct>>

tesselate { object { to_be_tessaleted } }

If clear and understandable source is your purpose.




> But consider that I'm talking about ideal tesselation with inheritance of
> parameters such no_image, texture, hollow etc. from base object.
> 

Ring some bells here about 'object'

> > > I know that some peoples don't like such word like "modeller" according to
> > > POV-script
> > > but in modellers there is taskbar with operations applied to object and
> > > rotation, scale and other linear operations are neighbours for
> >
> > Yes the classical mods,
> >
> > > twisting,
> > > bending, screwing
> >
> > This is the 'classical' problem with the POV approach: the intersection
> > of an object with a curved ray...
> 
> But I've resolved this in my putch a little :-)
> 

Yep, looks like we do not have the same definition for 'object'
If I understand your definition, and abuse it somehow,
all we need in Pov is the sphere object.

to make a cylinder, add a cylinder modifier
to make a box, add a box modifier
to make a cone, add a cone modifier
to make a superellipsoid, add a superellipsoid modifier
to make a quartic, ...

My definition of object is based on the internal structure,
once parsed.
So, if you look at the source, there is a sphere object and
another one which is an ellipsoid. 
and a box object,
and a cone/cylinder object,
and a superellipsoid object, and so on...

Basically, an object has a method which return all the intersection
of a ray with the object.

So from my current understanding of the tesselate patch (not opened yet),
it is an easy way to obtain a mesh object. I can hardly see tesselate as
a generic modifier, because pov does not end with the same parsed structure:

 without the modifier, the object structure holds pointers to the csg functions,
 with the modifier, the object structure holds pointers to the mesh functions.

It's too much for a modifier, at least for me ! 
(probably the only object which play this
kind of trick is the sphere when scaled unevenly: it replace the pointers
with the ones for the ellipsoid. But then, they are really similar object
and they are coded in the very same file, so that's very different from
your suggestion with tesselate).



> > The 'twist/bend/screw' cannot be applied to all objects, but you
> > could make them to be some new 'object' (?) that would take a
> > mesh-like object and some parameters:
> 
> What you mean by "cannot" ?
> In my patch they can.

Please, tell me where I can see the code for it.
I'm interested to see how you perform this miracle.

> 
> > twist { object {my_mesh}, <center.x,center.y,center.z>,<axis.x,axis.y,axis.z>,
> >angle... }
> > bend { object {my_mesh}, <center.x,center.y,center.z>,...}
> > screw { object {my_mesh}, <center.x,center.y,center.z>,<axis.x,axis.y,axis.z>,
> > pitch... }
> >
> > Then when parsing, your 'object' is twisted/bent/screwed by 'simply' applying
> > a blind transformation to each vertex of the mesh
> 
> This cause a lot of new types of objects.
> All this stuff shuld be IMO in object modifiers.

May be they may be just MESH modifiers. But I cannot still understand
how you can apply them into the resolving intersection of a line
and a sphere (e.g. as is currently the function for the sphere object)
when applied to a true basic object (and not a set of triangles)

> 
> > (beware: you not only have to transform the position of the vertex, but also
> > the normal... so the 'simply' is an overstatement).
> 
> perhaps you missed some images in p.b.i
> just look at topics with word "deform" sended by me

I also probably missed the deformation of the texture!
And in p.b.i, all I see from you is about ten posts, but
none with deform (but I seems to remember some sliced/twisted box,
so may be my newsreader is bogus)

> 
> when I twist box, my eyes see twisted box, not another type of object
> even if it is triangulated

Your eyes see a twisted box, but the code will probably see a mesh,
which may look like a box but is not really a box.
And if it is not really a box, it should not be parsed as a box...

Best regards, and probably more to come once I will have read the
tesselation patch...

Post a reply to this message

> Wlodzimierz ABX Skiba wrote:

>
> > > Moreover I found it counter-productive and dangerous:
> > > let's say we have a CSG operation (not a union) and
> > > you modify ONE of the component to tesselate while the
> > > other components remained unchanged.
> > > I'm not sure the CSG would still be possible.
> >
> > sometimes when you translate/rotate/scale component of CSG
> > rest of CSG dissapeare
>
> This may be a bug (unless the intersection/difference leave nothing,
> in such case I would considere that it is normal).

yes, I'm talking about  leaving nothing
but I can't understand your thinking that
tesselation as object modifier is dangerous
considering ideal tesselation - tesselated object has inside and
outside just like base object - than why it couldn't be part of csg ?

> > > Sincerely, I just like the way the tesselation object was introduced:
> > > it is a new object. dot.
> >
> > if you have large definition of object you must
> > jump over source to tesselate it : "tesselation {" at beginning and "}" at
end
> > when you put this as object modifier you must type only in one place.
>
> This is only a problem for the editor.

I agree

> And you may as well have a single line
> #local to_be_tessalated = <<your big construct>>
>
> tesselate { object { to_be_tessaleted } }

you still have to jump to write #local and tesselate, but nevermind

> > But consider that I'm talking about ideal tesselation with inheritance of
> > parameters such no_image, texture, hollow etc. from base object.
>
> Ring some bells here about 'object'

I'm sorry, my english is not enough to understand meaning of this sentence
is it some idom,  is it sarcasm ?

> > > > I know that some peoples don't like such word like "modeller" according
to
> > > > POV-script
> > > > but in modellers there is taskbar with operations applied to object and
> > > > rotation, scale and other linear operations are neighbours for
> > >
> > > Yes the classical mods,
> > >
> > > > twisting,
> > > > bending, screwing
> > >
> > > This is the 'classical' problem with the POV approach: the intersection
> > > of an object with a curved ray...
> >
> > But I've resolved this in my putch a little :-)
>
> Yep, looks like we do not have the same definition for 'object'
> If I understand your definition, and abuse it somehow,
> all we need in Pov is the sphere object.

I'm affraid you are completly wrong in understanding me

> My definition of object is based on the internal structure,
> once parsed.
> So, if you look at the source, there is a sphere object and
> another one which is an ellipsoid.
> and a box object,
> and a cone/cylinder object,
> and a superellipsoid object, and so on...

I think you are completly wrong in thinking about me.

> Basically, an object has a method which return all the intersection
> of a ray with the object.

right

> So from my current understanding of the tesselate patch (not opened yet),
> it is an easy way to obtain a mesh object.
> I can hardly see tesselate as
> a generic modifier, because pov does not end with the same parsed structure:
> without the modifier, the object structure holds pointers to the csg
functions,
> with the modifier, the object structure holds pointers to the mesh functions.

but for almost every modifer it calls soemthing like "method" to do something -
rotate, translate, set_flag

almost all modifiers are independent of type of object
(I'm talking about internal structure)
(independant this means that they have something like pointer->method or
function(pointer) and this "method" only internal depends of type of object)
never mind if it is sphere, cylinder or isosurface
if you smart replace pointer (internal) to currently parsed object you can make
it invisible
for that tesselated object is putted instead of original object

I play some years with pov
I don't like to be intruder in any community therefore since year I slowly read
whole news.povray.org to understand meaning of life :-) and I never meet opinion
that povsyntax should be mirror of internal structure. Perhaps I'm wrong but I
never meet. It shouldn't go far from internal but if there is something to
simply understand with syntax different than internal structure why not ?

my deformations are internal another kind of object and at first it was another
object in povsyntax
but when I announced my proposition in this group there was opposition that
deformation such like twist should be rather (compared with warp{}) modification
with proper parameters - therefore I changed syntax to object modifiers but
internals it is still another kind of object - it is just easier method to do it
for me becouse it has different method all_intersections()

> > > The 'twist/bend/screw' cannot be applied to all objects, but you
> > > could make them to be some new 'object' (?) that would take a
> > > mesh-like object and some parameters:
> >
> > What you mean by "cannot" ?
> > In my patch they can.
>
> Please, tell me where I can see the code for it.
> I'm interested to see how you perform this miracle.

I've not finished it yet and I don't want publish not finished code only to
proof something.
Although I don't think that I did miracle. I don't want fight with you. Whole
method was descibed here, in p.u-p with symbolic algorithm.
I don't think that my method is best way - it has limitations (reversable
deformations) and it has something like accuracy (like isosurfaces) but it works
for all objects, not only for meshes.

> > > Then when parsing, your 'object' is twisted/bent/screwed by 'simply'
applying
> > > a blind transformation to each vertex of the mesh
> >
> > This cause a lot of new types of objects.
> > All this stuff shuld be IMO in object modifiers.
>
> May be they may be just MESH modifiers.

meybe not

> But I cannot still understand
> how you can apply them into the resolving intersection of a line
> and a sphere (e.g. as is currently the function for the sphere object)
> when applied to a true basic object (and not a set of triangles)

by spliting ray to short segments and deform them and intersect base object

> > > (beware: you not only have to transform the position of the vertex, but
also
> > > the normal... so the 'simply' is an overstatement).
> >
> > perhaps you missed some images in p.b.i
>> just look at topics with word "deform" sended by me
>
> I also probably missed the deformation of the texture!

this is the part what I'm working on

> And in p.b.i, all I see from you is about ten posts, but
> none with deform
> (but I seems to remember some sliced/twisted box,
> so may be my newsreader is bogus)

http://www.abx.art.pl/pov/nonlinear/step3.jpg

> > when I twist box, my eyes see twisted box, not another type of object
> > even if it is triangulated
>
> Your eyes see a twisted box, but the code will probably see a mesh,
> which may look like a box but is not really a box.

I see the code, you not
believe me that code see not twisted box
even if I see twisted one

is there any other person who can vote against or opposite for:
a) deform as part of object modifiers
b) tesselate as part of object modifiers
it is not oblique voting for authors of patches but let's disscuse

ABX

Post a reply to this message

Chris Huff wrote:
> 
> It basically seems to be that triangles don't always end up where they
> are expected...every once in a while, in a very reproduceable but
> unpredictable manner, one (or more?) vertex of a triangle will end up
> where it shouldn't be, leaving a hole in the mesh. At least, that is
> what I could figure out...(A similar problem killed my warpable mesh
> patch.)

Funny. I had the same problem when I tried to do a tessellation macro, which
used the marching tetrahedrons technique (the same as Warp's patch, no?)...
Of course I never did bother to do a thorough debugging session, so 'twas
probably just something silly.

-- 
Margus Ramst

Personal e-mail: mar### [at] peakeduee
TAG (Team Assistance Group) e-mail: mar### [at] tagpovrayorg
Home page http://www.hot.ee/margusrt

Post a reply to this message

>Wlodzimierz ABX Skiba wrote:
>> and change Parse_*() functions.
>
>But not that one : do you have an idea of the number of functions
>to patch ?


26 in the official version, more in MegaPOV.

--
Mark

Post a reply to this message

This discussion is starting to be too long...

Wlodzimierz ABX Skiba wrote:
> 

> > Wlodzimierz ABX Skiba wrote:

> > > sometimes when you translate/rotate/scale component of CSG
> > > rest of CSG dissapeare
> >
> > This may be a bug (unless the intersection/difference leave nothing,
> > in such case I would considere that it is normal).
> 
> yes, I'm talking about  leaving nothing

Well, Off-topic, but I think that the CSG is not bugged.

> but I can't understand your thinking that
> tesselation as object modifier is dangerous
> considering ideal tesselation - tesselated object has inside and
> outside just like base object - than why it couldn't be part of csg ?

Because I have applied (yes, now) the tesselation patch to
a non-megapov version (my personal experimental 3.1),
and within 3.1, mesh cannot be part of a CSG difference/intersection.



> > > But consider that I'm talking about ideal tesselation with inheritance of
> > > parameters such no_image, texture, hollow etc. from base object.
> >
> > Ring some bells here about 'object'
> 
> I'm sorry, my english is not enough to understand meaning of this sentence
> is it some idom,  is it sarcasm ?

No sarcasm. Just the expression that your sentence triggered some thinking
in my head... Alas, my thinking seems to have been wrong.

>> > > > > twisting,
> > > > > bending, screwing
> > > >
> > > > This is the 'classical' problem with the POV approach: the intersection
> > > > of an object with a curved ray...
> > >
> > > But I've resolved this in my putch a little :-)
> >
> > Yep, looks like we do not have the same definition for 'object'
> > If I understand your definition, and abuse it somehow,
> > all we need in Pov is the sphere object.
> 
> I'm affraid you are completly wrong in understanding me
> 

As I do not have access to your patch, all I was able to do was 
guessing. Wrongly, I thought that to perform the twist/bend/screw,
you had transformed the object (let's it be a CSG or blob) into a mesh.
Then applying a transformation to the vertex of this mesh.


> 
> I think you are completly wrong in thinking about me.
> 

I agree.

> > Basically, an object has a method which return all the intersection
> > of a ray with the object.
> 
> right
> 
> > So from my current understanding of the tesselate patch (not opened yet),
> > it is an easy way to obtain a mesh object.
> > I can hardly see tesselate as
> > a generic modifier, because pov does not end with the same parsed structure:
> > without the modifier, the object structure holds pointers to the csg
> functions,
> > with the modifier, the object structure holds pointers to the mesh functions.
> 
> but for almost every modifer it calls soemthing like "method" to do something -
> rotate, translate, set_flag
> 

Rotate/translate/scale : yes, the object definition must provide a function
for them

Set flag: no, it's part of the core structure of an object and it
is handled by a single parser function.

> almost all modifiers are independent of type of object
> (I'm talking about internal structure)

Yes, because all type of object have the core structure of object.

> (independant this means that they have something like pointer->method or
> function(pointer) and this "method" only internal depends of type of object)
> never mind if it is sphere, cylinder or isosurface


> if you smart replace pointer (internal) to currently parsed object you can make
> it invisible
> for that tesselated object is putted instead of original object
> 

Well, you may have to reallocate the instanced object structure because some
object have bigger structure than other ones.

That's why I do not like the idea of an object modifier which nearly
substitute a structure for another.

When the script start saying it want a Pizza, I like to end
with a Pizza (even if you change the pepperoni for pineapple
and the sweet pepper for some corn).

From my point of view (nobody has to agree with it), the recipe
for the Pizza is in one single c file (sphere.c, csg.c, blob.c,
super.c, you name it...) and the other c files contains some
recipes for some other meals.

So, currently, my understanding of modifying on the fly the object
pointers via a generic object modifier , outside of the specific
object file, sounds to me like the script seems to ask for a Pizza
 and is finally served with a plate of Sushi.

I do not like this confusing approach, even if I can both like
Pizza and Sushi.


> I play some years with pov
> I don't like to be intruder in any community therefore since year I slowly read
> whole news.povray.org to understand meaning of life :-) and I never meet opinion
> that povsyntax should be mirror of internal structure. Perhaps I'm wrong but I
> never meet. It shouldn't go far from internal but if there is something to
> simply understand with syntax different than internal structure why not ?
>

This may be the start of a full chapter of holy war about the pov syntax,
should it be object oriented or not, should it looks like C++ or some
others language, and so on.

I do not care, as I'm not in charge of defending the syntax.
I would prefer to see your patch public, even done with a way I do not
like , rather than nothing. Afterall, the povteam will be able 
to change it to the way they want if they ever find it too confusing
or too complex or inadequate (or whatever).
 
> my deformations are internal another kind of object and at first it was another
> object in povsyntax

Sound good for me...

> but when I announced my proposition in this group there was opposition that
> deformation such like twist should be rather (compared with warp{}) modification
> with proper parameters 

Warp are built-in the engine, so that's easy when evaluating the texture to 
apply a warp to it. 
But deforming an object

> - therefore I changed syntax to object modifiers but
> internals it is still another kind of object - it is just easier method to do it
> for me becouse it has different method all_intersections()
> 

I think you should not have listen to the advisers, it would have make
me happier :-)
Or maybe there was a misunderstanding when people see your picture:
(I was assuming you used a mesh due to a final sentence stating in one
of your message that it may be easier to modify the vertex of a mesh)

May be some where saying that since the warp option already provide
a transformation of the space, it would be productive to have your 
transformation to use the existing warp, so that adding a warp automatically
add a new transformation of object.
This is logical when one thing you're modifying a mesh: you enter the 
original vertex in the warp and you exit of it with the new coordinate vertex.
In this case, it is logical to have a syntax such as

mesh { .... deform { warp_element } }

because there is a definitive added value to the fact of reusing the
transformation made by the warps.

> 
> I've not finished it yet and I don't want publish not finished code only to
> proof something.

Good, but I would very like to see how you resolve the problem
of the shadow and reflection (transforming an object only for the camera,
I can do it, but my headache starts when I start thinking about
the reflected ray and the lights ray...).

> Although I don't think that I did miracle.

Well, the twist/bend/screw thing is resisting many pov-programmers, including
me recently...

> I don't want fight with you. 

Neither do I.

> Whole
> method was descibed here, in p.u-p with symbolic algorithm.

I found the thread, but did not see the symbolic algorithm. 
Can you provide the reference of the message, thanks.


> I don't think that my method is best way - it has limitations (reversable
> deformations) and it has something like accuracy (like isosurfaces) but it works
> for all objects, not only for meshes.
> 

I'm curious... I will have to wait...

> >
> > May be they may be just MESH modifiers.
> 
> meybe not

Well, with my previous hypothesis (which is wrong), 
they would only have been modified Mesh.

Now, the tesselate patch introduce an interesting approach.
Applying a mesh-deform patch using warp definition 
as mesh modifier to a tesselated
object allow get all the warp being available to play
with all objects that can be tesselated.

> 
> > But I cannot still understand
> > how you can apply them into the resolving intersection of a line
> > and a sphere (e.g. as is currently the function for the sphere object)
> > when applied to a true basic object (and not a set of triangles)
> 
> by spliting ray to short segments and deform them and intersect base object
> 

Ouch... 





> 
> http://www.abx.art.pl/pov/nonlinear/step3.jpg
> 

Nice!!! 
I can imagine how to do it with a warp-based mesh deformation,
but you probably did it with a real checkered box.

> > > when I twist box, my eyes see twisted box, not another type of object
> > > even if it is triangulated
> >
> > Your eyes see a twisted box, but the code will probably see a mesh,
> > which may look like a box but is not really a box.
> 
> I see the code, you not
> believe me that code see not twisted box
> even if I see twisted one

I was wrong, 
But may I ask to have some background checkered planes and some
shadows of the box casted on them. I'm really curious.

> 
> is there any other person who can vote against or opposite for:
> a) deform as part of object modifiers
> b) tesselate as part of object modifiers
> it is not oblique voting for authors of patches but let's disscuse
> 
> ABX

May I ask who care ?
IMO, do your patch your way, then let people comment them and
use them.
I prefer to have a lot of patches than none... as long
as you do not break everything...

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