[Bf-committers] An easy to use damped spline

Fri Jan 2 09:38:58 CET 2015

On Fri, Jan 2, 2015 at 5:09 AM, Mikhail Rachinskiy
<wellmaderice at gmail.com> wrote:
> Hi Campbell, I think by “Nurbs Weights” Ronan ment this:
> http://wiki.blender.org/index.php/Doc:2.4/Manual/Modeling/Curves#Weight
> Which is not working since 2.5

It works, try change the W value.

> But (for me) this is not really an issue since Blender's control point
> weight interpolation isn't nearly accurate anyway:
> http://www.blender.org/forum/viewtopic.php?p=3426&sid=811ac0150dae2688cd55939d8410423f
> I'd be happy if surfaces were completly removed from Blender (since they're
> by fact useless) and developer concentraited on getting curves (both Bezier
> and Nurbs) to a decent Maya/3dsMax level, and getting libs such as
> openNURBS to be able to import nurbs as meshes in Blender (like Modo does).
>
> How is the GSoC openNURBS integration project is going on by the way?
> Haven't heard about it lately.
>
> --
> Regards,
> Mikhail Rachinskiy
> jewelcourses.com
> rachinskiy.com
>
> On Thu, Jan 1, 2015 at 5:02 PM, Campbell Barton <ideasman42 at gmail.com>
> wrote:
>
>> On Tue, Dec 30, 2014 at 12:41 AM, Ronan Ducluzeau <zeauron at gmail.com>
>> wrote:
>> > I just want to remind that currently nurbs weights are not working in
>> > master since 2.5.
>>
>> Tested, they work for nurbs curves & surfaces, but rather you use the
>> bug tracker if you found some case where they fail.
>>
>> > If someone is interested into improving Blender's nurbs; there is a lot
>> to
>> > do, anyways.
>> >
>> > 2014-12-29 1:47 GMT+01:00 Campbell Barton <ideasman42 at gmail.com>:
>> >
>> >> Heres a patch on Blender,
>> >> Removed the restriction of power-of-2 curve resolution.
>> >> https://developer.blender.org/P183
>> >>
>> >> However I don't see any significant advantage this offers over
>> >> existing nurbs calculation method, even though its quite efficient, it
>> >> would need to be extended to support different orders (currently
>> >> hard-coded to order-4), cyclic curves, nurbs weights etc...
>> >>
>> >> Just posting the patch for reference if anyone likes to check on the
>> code.
>> >>
>> >> On Mon, Dec 29, 2014 at 8:03 AM, Campbell Barton <ideasman42 at gmail.com>
>> >> wrote:
>> >> > Its available here:
>> >> > http://download.blender.org/ftp/ton/dspline.pdf
>> >> >
>> >> > On Mon, Dec 29, 2014 at 7:28 AM, joe <joeedh at gmail.com> wrote:
>> >> >> Do you have a link to a paper?
>> >> >> On Sep 28, 2014 10:45 AM, "Fred" <f.harthoorn at ziggo.nl> wrote:
>> >> >>
>> >> >>> Hi Campbell Barton,
>> >> >>>
>> >> >>> The amount of interpolation dots is 2^i, at the start of the demo
>> i =
>> >> >>> 4    (16 dots)
>> >> >>> if you change i = 7 (the limit in the demo) than there are 128
>> >> >>> interpolation dots.
>> >> >>>
>> >> >>> if I had set the limit in the demo to 10 then 1024 interpolation
>> dots
>> >> >>> was possible.
>> >> >>>
>> >> >>> If the spline is used in a 3 dimensional space,
>> >> >>> to compute an interpolated dot position takes:  dim * 10  clock
>> cycles
>> >> =
>> >> >>> 30 clock cycles.
>> >> >>> I hope that it is fast enough.
>> >> >>>
>> >> >>> If you like to have a curve to the last plotted dot you have to put
>> two
>> >> >>> dots on each other at the end.
>> >> >>> You will see that it is symmetrical again.
>> >> >>>
>> >> >>> Please change the number to 7 in the demo and you see a curved line
>> in
>> >> >>> stead of dots.
>> >> >>>
>> >> >>> Much more is possible with this spline because the first, second and
>> >> >>> third derivative (parameterized ) of the curve
>> >> >>> is available in real time.
>> >> >>>
>> >> >>> I think that much more can be invented with this spline technique.
>> >> >>> I think that with some research tangent handles can be constructed
>> as
>> >> >>> well (if you like them?).
>> >> >>> What I did in the demo was the most simple way of using it.
>> >> >>>
>> >> >>> The essence is: a 3th degree curve in two (x,y) or more directions
>> is
>> >> >>> differentiated three times, and then again integrated 3 times.
>> >> >>> With floating point this is impossible , because it is not exact,
>> the
>> >> >>> curve runs away.
>> >> >>> But with integer computing it is exact and the spline exact a 3th
>> >> degree
>> >> >>> curve.
>> >> >>>
>> >> >>> It can also be used in ten or more directions, but more then 3
>> >> >>> dimensions (x,y,z) is not  practical.
>> >> >>>
>> >> >>> Fred.
>> >> >>> --------------------------------------
>> >> >>> Fred schreef op 28-9-2014 om 18:30:
>> >> >>> > That is in the demo the case, because I programmed that  the first
>> >> plot
>> >> >>> > point is actually two points.
>> >> >>> > the spline uses 4 points p0, p1, p2, p3  and the interpolation is
>> >> >>> > between p1 and p2.
>> >> >>> >
>> >> >>> > Campbell Barton schreef op 28-9-2014 om 17:42:
>> >> >>> >> Checked the test application, and not sure if this is intended
>> but a
>> >> >>> >> simple triangle has uneven distribution.
>> >> >>> >>
>> >> >>> >> see: http://www.graphicall.org/ftp/ideasman42/fred_curve.png
>> >> >>> >>
>> >> >>> >> On Mon, Sep 29, 2014 at 1:32 AM, Dan McGrath <
>> >> danmcgrath.ca at gmail.com>
>> >> >>> wrote:
>> >> >>> >>> Cool, got them. Will take a look later. o/
>> >> >>> >>>
>> >> >>> >>> Dan
>> >> >>> >>>
>> >> >>> >>> On Sun, Sep 28, 2014 at 11:28 AM, Fred <f.harthoorn at ziggo.nl>
>> >> wrote:
>> >> >>> >>>
>> >> >>> >>>> Ok, It is uploaded to the directory incoming
>> >> >>> >>>>
>> >> >>> >>>> Dan schreef op 28-9-2014 om 17:15:
>> >> >>> >>>>> You could always upload it to our anonymous ftp via
>> >> >>> download.blender.org
>> >> >>> >>>>> (or ftp.blender.org) and put it into the incoming directory
>> (use
>> >> >>> passive
>> >> >>> >>>>> mode). From there was can fetch the files via
>> >> >>> >>>>> http://download.blender.org/ftp/incoming/
>> >> >>> >>>>>
>> >> >>> >>>>> Dan
>> >> >>> >>>>>
>> >> >>> >>>>> On Sun, Sep 28, 2014 at 11:05 AM, Fred <f.harthoorn at ziggo.nl>
>> >> wrote:
>> >> >>> >>>>>
>> >> >>> >>>>>> Campbell Barton
>> >> >>> >>>>>>
>> >> >>> >>>>>> I have tried to send it but it is rejected. So send me an
>> >> addres for
>> >> >>> >>>>>> upload.
>> >> >>> >>>>>>
>> >> >>> >>>>>> fred
>> >> >>> >>>>>>
>> >> >>> >>>>>>
>> >> >>> >>>>>> Campbell Barton schreef op 28-9-2014 om 16:51:
>> >> >>> >>>>>>> Could the project files be posted to a public URL?, Id like
>> to
>> >> be
>> >> >>> able
>> >> >>> >>>>>>> to look into this. but probably wont have time over the
>> coming
>> >> >>> weeks.
>> >> >>> >>>>>>>
>> >> >>> >>>>>>> The main source file compiles for me with minor edits on
>> >> >>> >>>>>>> Linux/FreePascal, but the demo relies on `Window` unit,
>> which I
>> >> >>> assume
>> >> >>> >>>>>>> is provided by delphi/windows.
>> >> >>> >>>>>>>
>> >> >>> >>>>>>> On Mon, Sep 29, 2014 at 12:36 AM, Dan McGrath <
>> >> >>> danmcgrath.ca at gmail.com
>> >> >>> >>>>>> wrote:
>> >> >>> >>>>>>>> Hey,
>> >> >>> >>>>>>>>
>> >> >>> >>>>>>>> Just save out the delphi project and zip it up and email it
>> >> to me
>> >> >>> >>>> direct
>> >> >>> >>>>>>>> via email I guess (the mailing list wouldn't allow such a
>> >> large
>> >> >>> >>>>>>>> attachement). I was attempting to compile it on linux, so
>> the
>> >> >>> compiled
>> >> >>> >>>>>>>> dll's wouldn't be of much use to me unfortunately.
>> >> >>> >>>>>>>>
>> >> >>> >>>>>>>> Thanks!
>> >> >>> >>>>>>>>
>> >> >>> >>>>>>>>
>> >> >>> >>>>>>>> Dan
>> >> >>> >>>>>>>>
>> >> >>> >>>>>>>> On Sun, Sep 28, 2014 at 10:06 AM, Fred <
>> f.harthoorn at ziggo.nl>
>> >> >>> wrote:
>> >> >>> >>>>>>>>
>> >> >>> >>>>>>>>> Hi Dan,
>> >> >>> >>>>>>>>>
>> >> >>> >>>>>>>>> Of course I can  send you the project.
>> >> >>> >>>>>>>>> I have made two versions:
>> >> >>> >>>>>>>>> 1) The spline is embedded in de demo:
>> >> >>> >>>>>>>>> 2) The spline is an external .dll, de demo calls
>> PSpline.dll
>> >> >>> >>>>>>>>>
>> >> >>> >>>>>>>>> Which one do you prefer?
>> >> >>> >>>>>>>>>
>> >> >>> >>>>>>>>> Fred.
>> >> >>> >>>>>>>>> ----------------
>> >> >>> >>>>>>>>>
>> >> >>> >>>>>>>>>
>> >> >>> >>>>>>>>>
>> >> >>> >>>>>>>>> Dan McGrath schreef op 28-9-2014 om 15:42:
>> >> >>> >>>>>>>>>> So is/was Turbo Pascal (limited in features; eg: objects
>> >> but no
>> >> >>> >>>>>> classes)
>> >> >>> >>>>>>>>>> and FreePascal+Lazarus (supports almost everything Delphi
>> >> does
>> >> >>> >>>> still?
>> >> >>> >>>>>>>>>> http://wiki.freepascal.org/Lazarus_For_Delphi_Users).
>> >> >>> >>>>>>>>>>
>> >> >>> >>>>>>>>>> Anyway, just thought it was neat to see code in pascal
>> (an
>> >> >>> elegant
>> >> >>> >>>>>>>>>> language, imho). Curious though, why not just give the
>> whole
>> >> >>> delphi
>> >> >>> >>>>>>>>> project
>> >> >>> >>>>>>>>>> and resource files so your forms can be built etc.? The
>> code
>> >> >>> seems
>> >> >>> >>>> to
>> >> >>> >>>>>>>>>> compile with some modifications here, but without the {$R
>> >> *.DFM}
>> >> >>> >>>>>> (*.lfm
>> >> >>> >>>>>>>>> in
>> >> >>> >>>>>>>>>> fp), one would have to manually rebuild the form :(
>> >> >>> >>>>>>>>>>
>> >> >>> >>>>>>>>>>
>> >> >>> >>>>>>>>>>
>> >> >>> >>>>>>>>>> On Sun, Sep 28, 2014 at 8:55 AM, Fred <
>> f.harthoorn at ziggo.nl
>> >> >
>> >> >>> wrote:
>> >> >>> >>>>>>>>>>
>> >> >>> >>>>>>>>>>> It's true, but Delphi is object oriented.
>> >> >>> >>>>>>>>>>>
>> >> >>> >>>>>>>>>>> Dan McGrath schreef op 28-9-2014 om 14:53:
>> >> >>> >>>>>>>>>>>> Standard Pascal, Turbo Pascal, Freepascal, Delphi; same
>> >> >>> language,
>> >> >>> >>>>>>>>>>> different
>> >> >>> >>>>>>>>>>>> dialect :)
>> >> >>> >>>>>>>>>>>>
>> >> >>> >>>>>>>>>>>> On Sun, Sep 28, 2014 at 8:43 AM, Fred <
>> >> f.harthoorn at ziggo.nl>
>> >> >>> >>>> wrote:
>> >> >>> >>>>>>>>>>>>> Actually it is Delphi
>> >> >>> >>>>>>>>>>>>>
>> >> >>> >>>>>>>>>>>>>
>> >> >>> >>>>>>>>>>>>> Dan McGrath schreef op 28-9-2014 om 14:35:
>> >> >>> >>>>>>>>>>>>>> Pascal, with inline assembler to boot! \o/ :)
>> >> >>> >>>>>>>>>>>>>>
>> >> >>> >>>>>>>>>>>>>> On Sun, Sep 28, 2014 at 6:46 AM, Ton Roosendaal <
>> >> >>> >>>> ton at blender.org>
>> >> >>> >>>>>>>>>>> wrote:
>> >> >>> >>>>>>>>>>>>>>> Hi,
>> >> >>> >>>>>>>>>>>>>>>
>> >> >>> >>>>>>>>>>>>>>> Fred told me he's not interested in getting
>> involved,
>> >> or
>> >> >>> >>>> setting
>> >> >>> >>>>>> up
>> >> >>> >>>>>>>>> a
>> >> >>> >>>>>>>>>>>>>>> project for his work.
>> >> >>> >>>>>>>>>>>>>>> He's retired now and just thought we might be
>> >> interested
>> >> >>> in a
>> >> >>> >>>>>>>>> research
>> >> >>> >>>>>>>>>>>>>>> topic he did.
>> >> >>> >>>>>>>>>>>>>>>
>> >> >>> >>>>>>>>>>>>>>> I've copied files he sent to me here;
>> >> >>> >>>>>>>>>>>>>>> http://download.blender.org/ftp/ton/
>> >> >>> >>>>>>>>>>>>>>>
>> >> >>> >>>>>>>>>>>>>>> It's a Dutch pdf and two pascal files.
>> >> >>> >>>>>>>>>>>>>>>
>> >> >>> >>>>>>>>>>>>>>> -Ton-
>> >> >>> >>>>>>>>>>>>>>>
>> >> >>> >>>>>>>>>>>>>>>
>> >> --------------------------------------------------------
>> >> >>> >>>>>>>>>>>>>>> Ton Roosendaal  -  ton at blender.org   -
>> >> www.blender.org
>> >> >>> >>>>>>>>>>>>>>> Chairman Blender Foundation - Producer Blender
>> >> Institute
>> >> >>> >>>>>>>>>>>>>>> Entrepotdok 57A  -  1018AD Amsterdam  -  The
>> >> Netherlands
>> >> >>> >>>>>>>>>>>>>>>
>> >> >>> >>>>>>>>>>>>>>>
>> >> >>> >>>>>>>>>>>>>>>
>> >> >>> >>>>>>>>>>>>>>> On 28 Sep, 2014, at 9:28, Aditia A. Pratama wrote:
>> >> >>> >>>>>>>>>>>>>>>
>> >> >>> >>>>>>>>>>>>>>>> HI Fred,
>> >> >>> >>>>>>>>>>>>>>>>
>> >> >>> >>>>>>>>>>>>>>>> Can you record a screencast/video demo to show how
>> it
>> >> >>> works?
>> >> >>> >>>>>>>>>>>>>>>>
>> >> >>> >>>>>>>>>>>>>>>> Regards,
>> >> >>> >>>>>>>>>>>>>>>> On Sep 28, 2014 2:14 PM, "Fred" <
>> f.harthoorn at ziggo.nl
>> >> >
>> >> >>> wrote:
>> >> >>> >>>>>>>>>>>>>>>>
>> >> >>> >>>>>>>>>>>>>>>>> I forgot to say, I have a two dimensional demo but
>> >> it is
>> >> >>> >>>>>> working
>> >> >>> >>>>>>>>> on
>> >> >>> >>>>>>>>>>> a
>> >> >>> >>>>>>>>>>>>>>>>> windows computer.
>> >> >>> >>>>>>>>>>>>>>>>>
>> >> >>> >>>>>>>>>>>>>>>>> Jacob Merrill schreef op 28-9-2014 om 02:07:
>> >> >>> >>>>>>>>>>>>>>>>>> would this make it so you can record F-curves
>> over
>> >> time
>> >> >>> >>>>>> better?
>> >> >>> >>>>>>>>>>>>>>>>>> right now recording in the engine gets slower the
>> >> >>> longer it
>> >> >>> >>>>>> runs,
>> >> >>> >>>>>>>>>>>>>>>>>> _______________________________________________
>> >> >>> >>>>>>>>>>>>>>>>>> Bf-committers mailing list
>> >> >>> >>>>>>>>>>>>>>>>>> Bf-committers at blender.org
>> >> >>> >>>>>>>>>>>>>>>>>>
>> >> http://lists.blender.org/mailman/listinfo/bf-committers
>> >> >>> >>>>>>>>>>>>>>>>>>
>> >> >>> >>>>>>>>>>>>>>>>> _______________________________________________
>> >> >>> >>>>>>>>>>>>>>>>> Bf-committers mailing list
>> >> >>> >>>>>>>>>>>>>>>>> Bf-committers at blender.org
>> >> >>> >>>>>>>>>>>>>>>>>
>> >> http://lists.blender.org/mailman/listinfo/bf-committers
>> >> >>> >>>>>>>>>>>>>>>>>
>> >> >>> >>>>>>>>>>>>>>>> _______________________________________________
>> >> >>> >>>>>>>>>>>>>>>> Bf-committers mailing list
>> >> >>> >>>>>>>>>>>>>>>> Bf-committers at blender.org
>> >> >>> >>>>>>>>>>>>>>>>
>> >> http://lists.blender.org/mailman/listinfo/bf-committers
>> >> >>> >>>>>>>>>>>>>>> _______________________________________________
>> >> >>> >>>>>>>>>>>>>>> Bf-committers mailing list
>> >> >>> >>>>>>>>>>>>>>> Bf-committers at blender.org
>> >> >>> >>>>>>>>>>>>>>>
>> >> http://lists.blender.org/mailman/listinfo/bf-committers
>> >> >>> >>>>>>>>>>>>>>>
>> >> >>> >>>>>>>>>>>>>> _______________________________________________
>> >> >>> >>>>>>>>>>>>>> Bf-committers mailing list
>> >> >>> >>>>>>>>>>>>>> Bf-committers at blender.org
>> >> >>> >>>>>>>>>>>>>>
>> http://lists.blender.org/mailman/listinfo/bf-committers
>> >> >>> >>>>>>>>>>>>>>
>> >> >>> >>>>>>>>>>>>> _______________________________________________
>> >> >>> >>>>>>>>>>>>> Bf-committers mailing list
>> >> >>> >>>>>>>>>>>>> Bf-committers at blender.org
>> >> >>> >>>>>>>>>>>>>
>> http://lists.blender.org/mailman/listinfo/bf-committers
>> >> >>> >>>>>>>>>>>>>
>> >> >>> >>>>>>>>>>>> _______________________________________________
>> >> >>> >>>>>>>>>>>> Bf-committers mailing list
>> >> >>> >>>>>>>>>>>> Bf-committers at blender.org
>> >> >>> >>>>>>>>>>>>
>> http://lists.blender.org/mailman/listinfo/bf-committers
>> >> >>> >>>>>>>>>>>>
>> >> >>> >>>>>>>>>>> _______________________________________________
>> >> >>> >>>>>>>>>>> Bf-committers mailing list
>> >> >>> >>>>>>>>>>> Bf-committers at blender.org
>> >> >>> >>>>>>>>>>> http://lists.blender.org/mailman/listinfo/bf-committers
>> >> >>> >>>>>>>>>>>
>> >> >>> >>>>>>>>>> _______________________________________________
>> >> >>> >>>>>>>>>> Bf-committers mailing list
>> >> >>> >>>>>>>>>> Bf-committers at blender.org
>> >> >>> >>>>>>>>>> http://lists.blender.org/mailman/listinfo/bf-committers
>> >> >>> >>>>>>>>>>
>> >> >>> >>>>>>>>> _______________________________________________
>> >> >>> >>>>>>>>> Bf-committers mailing list
>> >> >>> >>>>>>>>> Bf-committers at blender.org
>> >> >>> >>>>>>>>> http://lists.blender.org/mailman/listinfo/bf-committers
>> >> >>> >>>>>>>>>
>> >> >>> >>>>>>>> _______________________________________________
>> >> >>> >>>>>>>> Bf-committers mailing list
>> >> >>> >>>>>>>> Bf-committers at blender.org
>> >> >>> >>>>>>>> http://lists.blender.org/mailman/listinfo/bf-committers
>> >> >>> >>>>>> _______________________________________________
>> >> >>> >>>>>> Bf-committers mailing list
>> >> >>> >>>>>> Bf-committers at blender.org
>> >> >>> >>>>>> http://lists.blender.org/mailman/listinfo/bf-committers
>> >> >>> >>>>>>
>> >> >>> >>>>> _______________________________________________
>> >> >>> >>>>> Bf-committers mailing list
>> >> >>> >>>>> Bf-committers at blender.org
>> >> >>> >>>>> http://lists.blender.org/mailman/listinfo/bf-committers
>> >> >>> >>>>>
>> >> >>> >>>> _______________________________________________
>> >> >>> >>>> Bf-committers mailing list
>> >> >>> >>>> Bf-committers at blender.org
>> >> >>> >>>> http://lists.blender.org/mailman/listinfo/bf-committers
>> >> >>> >>>>
>> >> >>> >>> _______________________________________________
>> >> >>> >>> Bf-committers mailing list
>> >> >>> >>> Bf-committers at blender.org
>> >> >>> >>> http://lists.blender.org/mailman/listinfo/bf-committers
>> >> >>> >>
>> >> >>> > _______________________________________________
>> >> >>> > Bf-committers mailing list
>> >> >>> > Bf-committers at blender.org
>> >> >>> > http://lists.blender.org/mailman/listinfo/bf-committers
>> >> >>> >
>> >> >>>
>> >> >>> _______________________________________________
>> >> >>> Bf-committers mailing list
>> >> >>> Bf-committers at blender.org
>> >> >>> http://lists.blender.org/mailman/listinfo/bf-committers
>> >> >>>
>> >> >> _______________________________________________
>> >> >> Bf-committers mailing list
>> >> >> Bf-committers at blender.org
>> >> >> http://lists.blender.org/mailman/listinfo/bf-committers
>> >> >
>> >> >
>> >> >
>> >> > --
>> >> > - Campbell
>> >>
>> >>
>> >>
>> >> --
>> >> - Campbell
>> >> _______________________________________________
>> >> Bf-committers mailing list
>> >> Bf-committers at blender.org
>> >> http://lists.blender.org/mailman/listinfo/bf-committers
>> >>
>> > _______________________________________________
>> > Bf-committers mailing list
>> > Bf-committers at blender.org
>> > http://lists.blender.org/mailman/listinfo/bf-committers
>>
>>
>>
>> --
>> - Campbell
>> _______________________________________________
>> Bf-committers mailing list
>> Bf-committers at blender.org
>> http://lists.blender.org/mailman/listinfo/bf-committers
>>
> _______________________________________________
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-- 
- Campbell