View Full Version : JPatch - java based patch modeler

03 March 2003, 07:51 AM
sorry if this is a dupe post

from the site

JPatch is a 3D Modelling/Animation tool designed to model and animate "organic" shapes such as humans, animals, aliens, etc.

It is a bezier-spline modeller and works with so-called "Coon's patches" - the same patches are used by the popular Windows freeware modellers sPatch and Hamapatch and the commercial program Animation Master (they are called Hash patches there).

It is written entirely in Java (this means it should run on every platform that supports Java and Java 3D, including Microsoft Windows and Linux - Apple users see the note below). Don't be afraid of "poor Java performance". If you've got a Pentium III 500MHz or something equivalent it's fast enough to model complex shapes with several thousend control points in realtime. Actually it's nearly as fast as sPatch and a lot faster than Hamapatch!

It is free software (open source); you can redistribute it and/or modify it under the terms of the GNU General Public License.

JPatch is not a renderer (and never will be). Models can be exported as meshes of bicubic patches to POV-Ray and RenderMan renderers.

03 March 2003, 12:31 PM
Looks interesting, especially the bezier handles bit. There is still an old version of Renderman that ran on old Macs and it was free but I guess there's an Apple OS problem if jpatch works on Macs (I've read the authors notes) at all...

Whats the story with PC Renderman versions? Does Steve Jobs have a tie with Renderman or was it ILM software? If Steve Jobs owned it (through Pixar) - why did he prevent Mac users only from continuing to have access?

I've never used POV-ray and don't really want to but Renderman is a different issue. Has anyone tried jpatch?

03 March 2003, 01:04 PM
to answer my own question.. direct from this link -

So the reasons for this confusion between RenderMan the spec and PRMan the renderer are:

1. Pixar publishes and owns the RenderMan Interface Specification
2. RenderMan is a registered trademark of Pixar.
3. Pixar had the first implementation (PRMan).
4. PRMan has been used in a lot of movies.
5. Not only was PRMan the first implementation of the RenderMan
Specification, it was for many years the only implementation.

03 March 2003, 02:12 PM
Looks like a carbon copy of AM? Does Hash know about this?

03 March 2003, 03:52 PM
looks like a carbon copy

yeah maybe if it crashes etc, etc. :D

However, having looked further again- Hash has never given any regard to user requests or queries for RIB export. Yes I know this means there'll be a quote from someone still on the AMlist that that all Hash users love the fault-free renderer..

Out of further searching I found this -

a renderman application. Free - IRIX, Linux(Mac and PC), Windows + MacOSX

03 March 2003, 09:12 PM
How the heck do you use this? i downlaoded both version - source and file - and nothing. I cant see any .exe to run this? Any clue?

03 March 2003, 09:34 PM
Originally posted by koon69
How the heck do you use this? i downlaoded both version - source and file - and nothing. I cant see any .exe to run this? Any clue?

for a clue, open the file named "README.TXT" and, well, read it. (it's part of the jpatch download)

the 2 java requirements are available from (use the http download option)

03 March 2003, 04:09 PM
Originally posted by koon69
Looks like a carbon copy of AM? Does Hash know about this?

Hope so,

This happened to Nendo. The customers couldn't get what they wanted so someone went and built their own version and surpassed the original (wings3d).

Looks like someone decided to one up hash with a new patch modeler.

I think that with all the unemployed programmers out there you'll get some who will do this. Seems that people are getting tired of paying rediculous prices for buggy software or software that isn't up to date with the latest technology.

with luck it will keep hash motivated to listening to it's customers instead of banning them.


03 March 2003, 06:17 PM
1) the interesting thing done is the java foundation he's chosen. If Java3D worked on all platforms could he write one app only which could sit on the Java structure within any other OS?

2) This happened to Nendo. The customers couldn't get what they wanted so someone went and built their own version and surpassed the original (wings3d).

If this guy is serious, he should consider allowing animatable or constructable Polygon meshes - I'm not saying Hash should or shouldn't allow this as they've quite clearly said Patches not Polys. But imagine running a Pro studio and not being able to import a poly mesh or even scan models in to work with.

I know some of the big studios here (Framestore, HR3D in the UK) still have dedicated clay or plasticene modellers to make real models to scan in.

03 March 2003, 07:21 PM
Originally posted by alfiebabes
1) the interesting thing done is the java foundation he's chosen. If Java3D worked on all platforms could he write one app only which could sit on the Java structure within any other OS?

1) yup. if you have a fast enough processor you'd probably not notice.

The foundation is probably based on him being a java programmer. The wings3d programmer was a erlang (ericson phone programming language) coder who built it using erlang.

it's amazing there are all these great 3d programmers out there and no company has scooped them all up.


01 January 2005, 02:30 PM
Please understand ... Java's performance lags only in very specific areas ...

There is a byte code compiler (many times JIT) that actually converts to native code on a Just In Time basis as the classes are first loaded. The speed differents is NOT an order of magnitude different ... it's only a fractional difference in a lot of cases. Certainly if the Java guy has a good algorithm ... and the win32 native programmer does not care much .... the Java app with win ... and vice versa.

Bad programmers make Java look bad. There are short cuts novice Java programmers can take that reflect badly on the language if you are not a discerning analyst when it comes to performance. Memory tricks and a few other things are inherently slower.

Lots of times it's all about authoring a nice clean OpenGL display list. Once that's complete ... it does not matter if you authored with Java, C, or Erlang for example.

So don't be afraid.

01 January 2005, 04:20 PM
Works pretty well, but it actually seems limited compared to AM functionality. There doesn't appear to be a shaded wireframe mode which I think is kind of necessary, you need to see how your patches look. It seems stable enough too, nice job of coding.

Still though, compared to AM, it doesn't stack up - yet. I couldn't get the bias handles to work and the controls are different enough from AM to be confusing. I'm not learning two sets of controls! And I was hoping the key commands would be the same but they are not. Now if this is not for AM users, then I guess thats a moot point. :p

I did run a modeling test on a sphere, and then I did get a shaded view, but it showed dead 4 point patches that should render in a sphere no problem, and the command window said test okay, so something not quite right there. Still shows lots of promise.

01 January 2005, 02:46 AM
Funny. . I just mentioned this in another thread; hamapatch ( is similar in it's use of patches, has a great number of exportable formats, and polygon based modeling tools coming soon (

01 January 2005, 06:48 AM
take a look at this screenshot
look at the model icon on the right hand side... remind you of any other little yellow mascot?
not to mention the 5pt patch button
Rotate mode...
and curved /peak lines...

also notice the grouping of zoom move and rotate icons are in pretty much the same position just in reverse order and pretty similar to boot..

I'm all for open source but this is looks like its a little close to copyright infringement.

01 January 2005, 02:20 AM
Don't they have to be making money off it for it to be copyright infringement? :shrug:

01 January 2005, 10:43 AM

Regardless of whether the copied materials are offered for sale, distributed for free, or given to relatives, the copyright holder may claim infringement.

A copyright owner can sue for his losses or for the infringer’s profits, but not for the sum of the two amounts…. The copyright owner is allowed to waive damages (lost profits) and sue for the infringer’s gain…. But there is no basis in the law for requiring the infringer to give up more than his gain when it exceeds the copyright owners’ loss.

This is not to say that it's necessarily copyright infringement on the programmers for JPatch's or Hamapatch's part...that would be for people who know what's up with the code to determine. I am definitely not an expert, but I know it takes more than a couple of similar icons and that it can be as little as the difference of a line of code. Looking and functioning similar are one thing, but it could use an entirely different method to achieve that similarity.

…a copyright owner can’t prove infringement by pointing to features of his work that are found in the defendant’s work as well but that are so rudimentary, commonplace, standard, or unavoidable that they do not serve to distinguish one work within a class of works from another…The presence of such elements obviously does not forfeit copyright protection of the work as a whole, but infringement cannot be found on the basis of such elements alone; it is the combination of elements, or particular novel twists give to them, that supply the minimal originality required for copyright protection.

02 February 2005, 07:30 PM
Sorry to butt in, but I was just browsing your lovely forum and found this recent thread, and thought I'd fill in some of the gaps.

I've been following jpatch for over a year now. It's really not so much about making a replacement for animation master, as it is about making a useful character animator/modeller for pov-ray.

The author of jpatch, sacha ledinski seems to spend a bit of time at the povray newsgroups, and basically makes all his app announcements and some technical discussions there.

For those unfamiliar with povray, it's a freely available raytracer which, while it may not quite be on par with more professional packages, still has a small but loyal core of users for two reasons. #1. It's free #2. It has a robust scene description language, and the rendering engine itself is pretty high quality for its price.

The only problem is that there aren't really any robust modellers that work with povray. For human characters you're pretty much left to import models from poser.

Thus, jpatch, which everyone, mostly the author hopes to fill in that gap. (actually I don't speak for the author. I'm just one of those loyal users).

To be honest, it seems jpatch is taking as much inspiration from hamapatch and spatch as it is from animation master. I don't have the slightest worry about copyright infringements or replacing A:M. Especially considering how slow developement seems to be going. (it's just the one guy programming as far as I know)

so yes, I hope this post is somewhat enlightening.

02 February 2005, 10:45 PM
Sorry markyjerky, I disagree with you in many points on what you said about the 3d performances of Java.
It is true that Java3D is usefull and can suit for many low polygonal (patches) models.
But for large scenes or 3d models with large amount of Polygons or Patches, Java is down.
Theses are well known informations I'd like to recall, and that were confirmed several times when I tried and tried to make Jpatch working a bit while AM were still very very good. (I mean screen refreshment while turning the 3d model in real time).

Please, note that I'm not feeling against Jpatch project. But, Java3d cannot suit for large professionnal project, I've tested it for several projects and on very robust 3d workstations.

Just some words :)



02 February 2005, 12:06 AM
But for large scenes or 3d models with large amount of Polygons or Patches, Java is down.

To somewhat reiterate my earlier post, you wouldn't ever really need to do entire scenes in jpatch. Nor, as far as I'm aware, is it intended to be for producing scenes. As far as I know, it's primarily intended to produce individual models and animation for povray, and the composition of large scenes done directly in povray SDL, or in another povray modeler, therefore the performance of Java3d isn't as much of an issue as its broad cross platform compatibility; something hamapatch, spatch and A:M all lack.

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