This might be a bit of a stretch, plus it's my third image post, but here's
my "reflecting sphere on a checkered plane". 8-D

Well, it's not a checkered plane, it's a couple of dirty squares of
concrete.  And there's a big tank tread sitting on top of the reflective
sphere.

This is the output of my Moray plug-in that uses a hack job I did of the
M.O.P.S system at: http://perso.wanadoo.fr/mops/atelier2.htm
(not my site, I used the basis of this macro in building a "Belts" plugin).

The Belts Plugin:

The plug in takes and draws the centeres of a series of Sprockets, Wheels,
Idlers, and Returns.

Normally there is one sprocket.  I have to figure out how to calculate the
sprocket holes for the size of the treads, if you look closly at the
sprocket you'll see it doesn't line up with the tread.

The wheels are basically the roadwheels.  I don't have suspension (yet) I
hand placed the third wheel slightly up.  (couple of mouse clicks)

The return would be a roadwheel that can 'move' to adjust the track tension
(not implemented yet).

The idlers would show 'droop' between the return and the sprocket.  The
idler logic isn't implemented, so I cheated with a large wheel that is
tangental between the return and the sprocket.  If you look close you'll
notice it's not a real 'droop' it's a large circle, but it looks close
enough.

The ball bearing that the track is wrapped around is actually another road
wheel, defined as 'outside' the track and without an include file.

I have a few things to do before I can post the plug in:

misc bugs:
1) I have a few bugs with the way the controls refresh themselves in the
plugin
2) the width of the track doesn't show right, mostly because it's calculated
at run time. Basically my version always fills the number of tracks around
the wheels, so to make it the exact right length it can either stretch each
link in length, plus width and height, or just length.
3) I'd like to calculate the radius of the track 'droop' circule given a
number of tracks and the spacing between roadwheels and sockets.  The
drooping extra track would be hanging between the number of idlers.  If no
idlers, then between the return and the sprocket.
4)  Instead of calculating the length to fit the given number of tracks, I
want to make sure that a sprocket wheel fits the links 'exactly' - which
will mean cacluating the number of track links to fit the circumference of
the sprocket wheel.  This would probably end up being a partial track link,
so I have to implement track 'droop' before I can really do this one, or
move the return wheel to adjust the total length to be an integer number of
links.
5) Once I have 3 and 4, then I plan on writing a spline following trace()
macro to calculate the suspension movement based on an average between all
roadwheels.  I'm having problems with this.
6) The icon for 'belts' doesn't look like the nice new Moray icons, I need
to redraw it
7) If I can, I'd like to impelment the roadwheels as an actual Moray item
that can be drug - as if the Belts object had children.  Right, now, you
move the wheel picked under 'wheel' by changing the X,Y,Z numbers.  (X is
ignored currently, the belt has to be in a plane).
8) I have a 'width' to the drawn object in Moray, although it doens't line
up exactly right with the rendered image even though I've implemented the
vector math in include file pretty much as is.  Something is off.

The concrete:

The concrete tiles might eventually become a macro or Moray plugin - they
are created from Heightfields, not Iso-surfaces, so they generate fairly
quickly.  The cracks are generated through textures, and any number (or
none) of cracks can be generated, offset, etc.

There are faint grooves in the top of the concrete, in addition to the
casting seams.

The concrete actually looks better without the stains, but I was
experimenting with extreme concrete - more or less the inside of a garage,
not the mars interstate where it is now <G>.

There are small rocks poking through some of the cracked areas in the
concrete (but not all the areas - two of the cracks go all the way through).
This is supposed to look like the concrete aggregate.

Clearly, there needs to be the 'rest of the tank' to go with the tracks,
this is a first initial post showing the concrete and the tracks.  I'll post
screen shots of what the Moray plugin UI looks like to the Moray binaries
group once I figure out how to do the scene interface for the wheel
locations.

Comments?

        == John ==

Post a reply to this message

Attachments:
Download 'belttest3.jpg' (118 KB)

Preview of image 'belttest3.jpg'

John D. Gwinner wrote:
> This might be a bit of a stretch, plus it's my third image post, but here's
> my "reflecting sphere on a checkered plane". 8-D
> 
> Well, it's not a checkered plane, it's a couple of dirty squares of
> concrete.  And there's a big tank tread sitting on top of the reflective
> sphere.
> 
> This is the output of my Moray plug-in that uses a hack job I did of the
> M.O.P.S system at: http://perso.wanadoo.fr/mops/atelier2.htm
> (not my site, I used the basis of this macro in building a "Belts" plugin).
> 
> The Belts Plugin:
> 
> The plug in takes and draws the centeres of a series of Sprockets, Wheels,
> Idlers, and Returns.
> 
> Normally there is one sprocket.  I have to figure out how to calculate the
> sprocket holes for the size of the treads, if you look closly at the
> sprocket you'll see it doesn't line up with the tread.
> 
> The wheels are basically the roadwheels.  I don't have suspension (yet) I
> hand placed the third wheel slightly up.  (couple of mouse clicks)
> 
> The return would be a roadwheel that can 'move' to adjust the track tension
> (not implemented yet).
> 
> The idlers would show 'droop' between the return and the sprocket.  The
> idler logic isn't implemented, so I cheated with a large wheel that is
> tangental between the return and the sprocket.  If you look close you'll
> notice it's not a real 'droop' it's a large circle, but it looks close
> enough.
> 
> The ball bearing that the track is wrapped around is actually another road
> wheel, defined as 'outside' the track and without an include file.
> 
> I have a few things to do before I can post the plug in:
> 
> misc bugs:
> 1) I have a few bugs with the way the controls refresh themselves in the
> plugin
> 2) the width of the track doesn't show right, mostly because it's calculated
> at run time. Basically my version always fills the number of tracks around
> the wheels, so to make it the exact right length it can either stretch each
> link in length, plus width and height, or just length.
> 3) I'd like to calculate the radius of the track 'droop' circule given a
> number of tracks and the spacing between roadwheels and sockets.  The
> drooping extra track would be hanging between the number of idlers.  If no
> idlers, then between the return and the sprocket.
> 4)  Instead of calculating the length to fit the given number of tracks, I
> want to make sure that a sprocket wheel fits the links 'exactly' - which
> will mean cacluating the number of track links to fit the circumference of
> the sprocket wheel.  This would probably end up being a partial track link,
> so I have to implement track 'droop' before I can really do this one, or
> move the return wheel to adjust the total length to be an integer number of
> links.
> 5) Once I have 3 and 4, then I plan on writing a spline following trace()
> macro to calculate the suspension movement based on an average between all
> roadwheels.  I'm having problems with this.
> 6) The icon for 'belts' doesn't look like the nice new Moray icons, I need
> to redraw it
> 7) If I can, I'd like to impelment the roadwheels as an actual Moray item
> that can be drug - as if the Belts object had children.  Right, now, you
> move the wheel picked under 'wheel' by changing the X,Y,Z numbers.  (X is
> ignored currently, the belt has to be in a plane).
> 8) I have a 'width' to the drawn object in Moray, although it doens't line
> up exactly right with the rendered image even though I've implemented the
> vector math in include file pretty much as is.  Something is off.
> 
> The concrete:
> 
> The concrete tiles might eventually become a macro or Moray plugin - they
> are created from Heightfields, not Iso-surfaces, so they generate fairly
> quickly.  The cracks are generated through textures, and any number (or
> none) of cracks can be generated, offset, etc.
> 
> There are faint grooves in the top of the concrete, in addition to the
> casting seams.
> 
> The concrete actually looks better without the stains, but I was
> experimenting with extreme concrete - more or less the inside of a garage,
> not the mars interstate where it is now <G>.
> 
> There are small rocks poking through some of the cracked areas in the
> concrete (but not all the areas - two of the cracks go all the way through).
> This is supposed to look like the concrete aggregate.
> 
> Clearly, there needs to be the 'rest of the tank' to go with the tracks,
> this is a first initial post showing the concrete and the tracks.  I'll post
> screen shots of what the Moray plugin UI looks like to the Moray binaries
> group once I figure out how to do the scene interface for the wheel
> locations.
> 
> Comments?
> 
>         == John ==
> 
> 
> 
> 

tell me you're animating it, please please

shouldn't one of spheres be flattened?

stephen

Post a reply to this message

----- Original Message ----- 
From: "stephen parkinson" <ste### [at] zmemw16demoncouk>

> tell me you're animating it, please please
>
> shouldn't one of spheres be flattened?
>
> stephen

Yes I am!   It's perfect for the IRTC right now ("Classic Sci-Fi")

This was really just a test image, so I used normal spheres.  If they are
ball bearings though they wouldn't squish much - the point of tank treads is
to spread the weight out.  The ground pressure is only about double a
regular foot soldier.

It would probably crack the concrete though.

My plan was to drive the tank/treads across a height field and CSG a shallow
indendation behind it.  I was trying to use some trace() statements to find
the height of the terrain and 'tilt' the tank body to match, but most of the
code I've found is for a 4 wheel object.  It just doesn't look right when it
goes over large objects (craters).

If you look through the forum at my earlier image you'll get an idea of what
the tank looks like :)

I'm having a bad problem with Mechsim right now, looking at the deadline,
and in a state of mild panick!

        == John ==

Post a reply to this message

John D. Gwinner wrote:

<snip />
> 
> Comments?

Awesome texturing!
Can't wait to see the little green martians gettin' squished underneath >:-D

-- 
Respectfully,
Dan P
http://<broken link>

Post a reply to this message

> Awesome texturing!
Thanks!

Tracks or the concrete?

Is the concrete too 'stained' or does it look OK? I was going to tone it
down a bit.

> Can't wait to see the little green martians gettin' squished underneath
>:-D

he he ... well, it's not that but I can't tell yet

        == John ==

Post a reply to this message

John D. Gwinner wrote:
>>Awesome texturing!
> 
> Thanks!
> 
> Tracks or the concrete?

I was thinkin' the wheels and the landscape looked cool. Adding a normal 
{ bumps scale <0.1, 0.1, 0.1> } to the wheels and turning down the 
specular a bit might make it look more like rubber too.

> Is the concrete too 'stained' or does it look OK? I was going to tone it
> down a bit.

I think it looks great! :-) I'm not sure what some of the circular spots 
are yet, though -- I was thinking they were shadows at first.

Also, you'll find reflective spheres look better if they have just a bit 
less than 1 reflection -- in nature, reflection 1 is not possible (not 
even with a mirror) and the eye can see that. Plus, it adds a little bit 
of depth too.

>>Can't wait to see the little green martians gettin' squished underneath
>>:-D
> 
> 
> he he ... well, it's not that but I can't tell yet
> 
>         == John ==

Aw :-( IMBJR isn't the /only/ guy who wants to see blood and guts (as 
long it is green!) :-P
-- 
Respectfully,
Dan P
http://<broken link>

Post a reply to this message

John D. Gwinner wrote:
> Comments?

Nice tracks!
-- 
Rick

Kitty5 NewMedia http://Kitty5.com
POV-Ray News & Resources http://Povray.co.uk
TEL : (+44) 0845 1083740 - ICQ : 15776037

PGP Public Key : http://pgp.kitty5.com

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"John D. Gwinner" <joh### [at] cornelledu> wrote in message
news:406d0bbe@news.povray.org...

Nice. Will look for the animation.

 -Shay

Post a reply to this message

"Dan P" <dan### [at] yahoocom> wrote in message
news:4070a719$1@news.povray.org...

> I think it looks great! :-) I'm not sure what some of the circular spots
> are yet, though -- I was thinking they were shadows at first.

Oil drops, sorta; any kind of road probably has more smaller ones though.

> Also, you'll find reflective spheres look better if they have just a bit
> less than 1 reflection -- in nature, reflection 1 is not possible (not
> even with a mirror) and the eye can see that. Plus, it adds a little bit
> of depth too.

Thanks, I really sort of threw them in for this one image.  They wouldn't be
in the animation.

> Aw :-( IMBJR isn't the /only/ guy who wants to see blood and guts (as
> long it is green!) :-P

Oh, I have a whole bunch of blood and guts planned, but I quickly found out
the limitations of 10Meg for the IRTC :(

I also have an issue with my dynamics library so the initial movie will
probably be just a little driving on the concrete.  And if I can do it in
the next 2-3 days, a neutral turn of course!

        == John ==

Post a reply to this message

Hi John D. Gwinner, you recently wrote in povray.binaries.images:

> 7) If I can, I'd like to impelment the roadwheels as an actual Moray item
> that can be drug - as if the Belts object had children.  Right, now, you
> move the wheel picked under 'wheel' by changing the X,Y,Z numbers.  (X is
> ignored currently, the belt has to be in a plane).
Just a quick pointer... the Controller interface will allow you to
move around stuff in your plugin. This what Mike Weber does in his
BSPline plugin (check it out to see what I mean). And that's also what
I do in the Ruler plugin....

- Lutz
  email : lut### [at] stmuccom
  Web   : http://www.stmuc.com/moray

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