Greg M. Johnson <gre### [at] my-dejanewscom> wrote:
: Cool.  It would be neat if it had animation support.

  What kind of animation support you mean? Povray has animation support, FYI.

-- 
main(i,_){for(_?--i,main(i+2,"FhhQHFIJD|FQTITFN]zRFHhhTBFHhhTBFysdB"[i]
):5;i&&_>1;printf("%s",_-70?_&1?"[]":" ":(_=0,"\n")),_/=2);} /*- Warp -*/

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Pov makes wonderful TGA's. Pov can make a still image where things happen based
on a clock variable.

I want an animation to run based on my algorithm all day.

look at.
http://hmt.com/cwr/boids.html


Nieminen Juha wrote:

> Greg M. Johnson <gre### [at] my-dejanewscom> wrote:
> : Cool.  It would be neat if it had animation support.
>
>   What kind of animation support you mean? Povray has animation support, FYI.
>
> --
> main(i,_){for(_?--i,main(i+2,"FhhQHFIJD|FQTITFN]zRFHhhTBFHhhTBFysdB"[i]
> ):5;i&&_>1;printf("%s",_-70?_&1?"[]":" ":(_=0,"\n")),_/=2);} /*- Warp -*/

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Nieminen Juha wrote:

>   Ok, ok, Java is not 100 times as slow as C, but at least 10 times, and you
> seldom have 10 computers to render your scene.

Actually, for full MPEG-2 decoding in pure Java, it's only about half as slow as
C. I guess the gap has been closing since you last checked  :-)

But still, I would recommend against doing raytracing with Java. And this is
coming from "Mr. Java". :-)

--
"My new computer's got the clocks, it rocks
But it was obsolete before I opened the box" - W.A.Y.

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Nieminen Juha wrote:

> (Yes, I know that java coders can tell a hundred and one reasons why those
> features are "not needed" or even "dangerous", but don't bother, I have heard
> all of them but still find them really handy (specially templates).)
>

If you do that is good. But it is true that they are dangerous, and easily
abused. Especially that multiple-inheritance one. Unfortunately, most
programmers are not quite as savvy as yourself, and we end up with some horrible
stuff to maintain. (BTW, this is all honest, and not said in a flaming tone)


>   Btw, a little problem (just for curiosity, not for flaming): Make a
> generic swap-function in Java :)

Here's the solution:
"Why?"

Here's another Java question: where are objects created? On the stack or on the
heap?
Answer: doesn't matter. Why should you care?

One should not do C++ things in a Java way, and vice versa. How about writing an
object-oriented debugging HTTP proxy program in under 400 lines of fully
commented code, or a high-performance video codec?

Java 3D modeler if you are using Java3D = good.
Java POV-Ray = bad.
Java POV-Ray distribution system = good. (shameless self-promotion)

--
"My new computer's got the clocks, it rocks
But it was obsolete before I opened the box" - W.A.Y.

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Jon A. Cruz <jon### [at] geocitiescom> wrote:
:>   Btw, a little problem (just for curiosity, not for flaming): Make a
:> generic swap-function in Java :)

: Here's the solution:
: "Why?"

  This is the typical answer when there isn't a solution. Perhaps this specific
example is seldom really useful, but it was only an example. It demonstrates
that there are some things that can't be done. It shouldn't be very hard to
think about a similar problem which is more radical but can't be done for
the same reason.
  Why is it so hard to admit that there are things that you just can't do
with java and that you have to live with that if you are coding java?
  There are things that are very difficult, if not impossible to do with C++
and I don't have any problem in admitting it. I know that C++ has some very
bad things. I know that it would need some features which would make it more
safe. I admit it and I don't have any problem doing it.
  What I wonder why is it so hard for java coders to admit that java is not
perfect? Java seems to be a holy thing and if you criticize it you are
committing blasphemy.
  Java coders seem to be like windows users: When they can't do something then
they convince themselves that actually they don't really need it.

-- 
main(i,_){for(_?--i,main(i+2,"FhhQHFIJD|FQTITFN]zRFHhhTBFHhhTBFysdB"[i]
):5;i&&_>1;printf("%s",_-70?_&1?"[]":" ":(_=0,"\n")),_/=2);} /*- Warp -*/

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Greg M. Johnson <gre### [at] my-dejanewscom> wrote:
: Pov makes wonderful TGA's. Pov can make a still image where things happen based
: on a clock variable.

: I want an animation to run based on my algorithm all day.

  Sorry, I still don't understand what do you mean.

  Povray can make a series of images. You just have to tell it how many
images it has to create. You can convert those images to an animation format
with any converter you like.

-- 
main(i,_){for(_?--i,main(i+2,"FhhQHFIJD|FQTITFN]zRFHhhTBFHhhTBFysdB"[i]
):5;i&&_>1;printf("%s",_-70?_&1?"[]":" ":(_=0,"\n")),_/=2);} /*- Warp -*/

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Nieminen Juha wrote:

>   Java coders seem to be like windows users: When they can't do something then
> they convince themselves that actually they don't really need it.

And why is it that when people that favor using unix/linux have to decide
which OS to pick on for an example always choose windows as the platform
to pick on when they do :)

-- 
Ken Tyler -  1100+ Povray, Graphics, 3D Rendering, and Raytracing Links:
http://home.pacbell.net/tylereng/index.html http://www.povray.org/links/

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Nieminen Juha wrote:
> 
> Greg M. Johnson <gre### [at] my-dejanewscom> wrote:
> : Pov makes wonderful TGA's. Pov can make a still image where things happen based
> : on a clock variable.
> 
> : I want an animation to run based on my algorithm all day.
> 
>   Sorry, I still don't understand what do you mean.
> 
>   Povray can make a series of images. You just have to tell it how many
> images it has to create. You can convert those images to an animation format
> with any converter you like.

I think what Greg needs is not so much a "movie" amination capability
as much as he needs a screen saver type program routine that runs his
sript continiously. At least that is the way I percieve it.

-- 
Ken Tyler -  1100+ Povray, Graphics, 3D Rendering, and Raytracing Links:
http://home.pacbell.net/tylereng/index.html http://www.povray.org/links/

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Ken <tyl### [at] pacbellnet> wrote:
: And why is it that when people that favor using unix/linux have to decide
: which OS to pick on for an example always choose windows as the platform
: to pick on when they do :)

  Perhaps because there is no other OS which is so irritating? ;)

-- 
main(i,_){for(_?--i,main(i+2,"FhhQHFIJD|FQTITFN]zRFHhhTBFHhhTBFysdB"[i]
):5;i&&_>1;printf("%s",_-70?_&1?"[]":" ":(_=0,"\n")),_/=2);} /*- Warp -*/

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Nieminen Juha wrote:

> Jon A. Cruz <jon### [at] geocitiescom> wrote:
> :>   Btw, a little problem (just for curiosity, not for flaming): Make a
> :> generic swap-function in Java :)
>
> : Here's the solution:
> : "Why?"
>
>   This is the typical answer when there isn't a solution. Perhaps this specific
> example is seldom really useful, but it was only an example. It demonstrates
> that there are some things that can't be done. It shouldn't be very hard to
> think about a similar problem which is more radical but can't be done for
> the same reason.
>   Why is it so hard to admit that there are things that you just can't do
> with java and that you have to live with that if you are coding java?
>   There are things that are very difficult, if not impossible to do with C++
> and I don't have any problem in admitting it. I know that C++ has some very
> bad things. I know that it would need some features which would make it more
> safe. I admit it and I don't have any problem doing it.
>   What I wonder why is it so hard for java coders to admit that java is not
> perfect? Java seems to be a holy thing and if you criticize it you are
> committing blasphemy.
>   Java coders seem to be like windows users: When they can't do something then
> they convince themselves that actually they don't really need it.
>

First of all the "why" solution was not the usual cop-out, but rather in this case
an actual answer that was supposed to make the reader step back a level and switch
from asking "how can I implement this" to "why should I be doing this" (one thing
that more programmers should be doing). But the main intent was to show that the
particular operation in question was not a good architectural choice for Java.

As far as the point that sometimes one should use Java and sometimes one should
use C++, I am in total agreement. I gave an example where Java was a good choice,
then an example where C++ was a good choice. Here's another one. Don't do a
MPEG-II decoder in pure Java. You'll probably only get 50% the performance of
C/C++.

I used to say "Don't try to write games like Quake in Java", but then someone did
an interface library so that you can use Java to write Quake II games. What is
even more interesting is that later versions exposed the Quake map & all it's
objects using the standard DOM architecture. That's the same why you'd examine and
manipulate an HTML document in IE, or most standard XML documents (even in C++).

But I will say again that I think a Java version of POV-Ray is just not the best
idea. If they are planing on doing a native C library to do the number intensive
part, then they would be better off shelling out to call POV-Ray itself. The
resulting Java program would stay cross-platform, and the performance would be
good.

BTW, this is a bit interesting: http://www.cs.brown.edu/people/jks/thesis.html

--
"My new computer's got the clocks, it rocks
But it was obsolete before I opened the box" - W.A.Y.

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