randall jones

I've cleaned up the patch which I've been using to record my own work 

lately, in hopes that it will be generally useful. I have tried to 

address some of the most common problems regarding patch preview and 

A handy tool for managing both real-time preview and offline 

rendering in Jitter OpenGL patches. Render_node can record both audio 

and visuals offline in sync. Visuals can be rendered with proper 

temporal antialiasing or "motion blur." Playback is controlled via a 

There are a few simple steps to making a patch which will work with 

render_node. These are demonstrated in the companion 

Render_node can render your OpenGL scenes through shader plugins, 

both offline and in realtime. Examples are in the "plugins" folder. 

Tested on OS X only. Theoretically, everything is cross-platform. 

If you are on Windows and you find yourself applying tweaks to get it 

to work, please share and I'll redistribute.

I am currently getting some errors using filepath for my 

initialization, but the patch is working OK. If some javascripts or 

shaders are not found when you run the patch, then this is causing a 

problem. If anyone has worked out a good way to add a subdirectory 

of the patch's folder to the search path, let me know.

I've cleaned up the patch which I've been using to record my own work  
lately, in hopes that it will be generally useful.  I have tried to  
address some of the most common problems regarding patch preview and  
rendering.  From the help file:

A handy tool for managing both real-time preview and offline  
rendering in Jitter OpenGL patches. Render_node can record both audio  
and visuals offline in sync. Visuals can be rendered with proper  
temporal antialiasing or "motion blur."  Playback is controlled via a  
timeline interface.

There are a few simple steps to making a patch which will work with  
render_node. These are demonstrated in the companion  
"render_node_test_pattern."

Render_node can render your OpenGL scenes through shader plugins,  
both offline and in realtime. Examples are in the "plugins" folder.  
Open one to activate it.

Tested on OS X only.  Theoretically, everything is cross-platform.   
If you are on Windows and you find yourself applying tweaks to get it  
to work, please share and I'll redistribute.

I am currently getting some errors using filepath for my  
initialization, but the patch is working OK.  If some javascripts or  
shaders are not found when you run the patch, then this is causing a  
problem.  If anyone has worked out a good way to add a subdirectory  
of the patch's folder to the search path, let me know.

Please visit http://2uptech.com/archive.html to download.

render_node-for-jitter

I think the best way to add a subfolder to a patch's path is to do the

->use something like this to get the folder path:

var patchFile = new File(patch.filepath);

var patchPath = patchFile.foldername.substring(0,

Then, there's a Max object (I forget the name) for adding search

paths. Use it on conjunction with the JS script to add appropriate

One caveat is that the patch ahs to be fully loaded for this to work. 

So, for things like shaders etc that depend on it, you will have to

load them after the JS loadbang method executes.

I think the best way to add a subfolder to a patch's path is to do the
following:

in a loadbang JS method:
->use something like this to get the folder path:
var patch = this.patcher;
var patchFile = new File(patch.filepath);
var patchPath = patchFile.foldername.substring(0,
patchFile.foldername.length-1);

Then, there's a Max object (I forget the name) for adding search
paths.   Use it on conjunction with the JS script to add appropriate
subdirectories.

One caveat is that the patch ahs to be fully loaded for this to work. 
So, for things like shaders etc that depend on it, you will have to
load them after the JS loadbang method executes.

Thanks for the help. This is basically what I did in Max, using 

thispatcher and filepath. You can ask thispatcher for the patcher's 

path. But filepath is returning errors (-1) when I add the 

subpaths. Does the render_node patch work for you? I'd be keen to 

Thanks for the help.  This is basically what I did in Max, using  
thispatcher and filepath.  You can ask thispatcher for the patcher's  
path.  But filepath is returning errors (-1) when I add the  
subpaths.  Does the render_node patch work for you?  I'd be keen to  
hear if it works on Windows as well.

The patch is semi-functional. You have some paths for pictctrl that

are specific to your machine on there. Also, I couldn't get the

plugins to work although they were registered. It could just be my

misunderstanding the patch. I would need to look at how it's

constructed to give more detailed analysis.

Also, what's the purpose of the blur? I'm not familiar with the

technique of temporally blurring recordings of renderings.

The patch is semi-functional.  You have some paths for pictctrl that
are specific to your machine on  there.  Also, I couldn't get the
plugins to work although they were registered.  It could just be my
misunderstanding the patch.  I would need to look at how it's
constructed to give more detailed analysis.

Also, what's the purpose of the blur?  I'm not familiar with the
technique of temporally blurring recordings of renderings.

After thinking about it more, I think the whole relative path thing

should be rolled into a max external. Something that would

automatically add subpaths to the search path if it's in a patch.

After thinking about it more, I think the whole relative path thing
should be rolled into a max external.  Something that would
automatically add subpaths to the search path if it's in a patch.

Adding the render_node folder to your search path should solve all of 

the file problems for the time being until I get the filepath error 

sorted. If you do this, open the patch, open the test pattern, and 

hit play, you should see a rendered scene. Did you try the help 

hints? Hopefully they will explain the looping timeline and other 

The bias plugin defaults to look like the input image-- you'll need 

to tweak the swatches to change the colors. The lumadisplace plugin 

should produce an obvious warp by default.

re: blur. Motion blur (temporal antialiasing) is needed just like 

spatial antialiasing to make computer animations look decent. It's 

why film looks good even at 24fps-- the shutter records an 

integration of the light in the scene over time through what is 

essentially a box filter. High-end packages like PRRenderman 

implement motion blur through stochastic oversampling of each frame. 

Accumulating frames on the GPU is what I'm doing-- with enough 

frames, it looks good. Really it should be done adaptively, but let 

Adding the render_node folder to your search path should solve all of  
the file problems for the time being until I get the filepath error  
sorted.  If you do this, open the patch, open the test pattern, and  
hit play, you should see a rendered scene.  Did you try the help  
hints?  Hopefully they will explain the looping timeline and other  
controls.

The bias plugin defaults to look like the input image-- you'll need  
to tweak the swatches to change the colors.  The lumadisplace plugin  
should produce an obvious warp by default.

re: blur.  Motion blur (temporal antialiasing) is needed just like  
spatial antialiasing to make computer animations look decent.  It's  
why film looks good even at 24fps-- the shutter records an  
integration of the light in the scene over time through what is  
essentially a box filter.  High-end packages like PRRenderman  
implement motion blur through stochastic oversampling of each frame.   
Accumulating frames on the GPU is what I'm doing-- with enough  
frames, it looks good.  Really it should be done adaptively, but let  
me get the patch working first...

Thanks a lot for sharing this! I hope I can figure out how to adapt my

patches to render_node. The test animation is working almost without

problems on windows too. The only thing I encountered is a distortion in the

output movie, similar to what I experience if I use @doublebuffer 0 on a

window in any jitter patch (this has always been like that on my computer).

Only now it's not visible in the jit.window (when the patch is running or

My animations use a lot of midi-triggered ramps and lfo's synced to an

external sequencer. I used to just divide the time constants by 4 and run

the render metro at fps/4 while recording to disk.

Any thoughts on how to adapt this to your smpte based render? Thanks again.

Thanks a lot for sharing this! I hope I can figure out how to adapt my
patches to render_node. The test animation is working almost without
problems on windows too. The only thing I encountered is a distortion in the
output movie, similar to what I experience if I use @doublebuffer 0 on a
window in any jitter patch (this has always been like that on my computer).
Only now it's not visible in the jit.window (when the patch is running or
recording) but just the output movie.

My animations use a lot of midi-triggered ramps and lfo's synced to an
external sequencer. I used to just divide the time constants by 4 and run
the render metro at fps/4 while recording to disk.

I was able to get the render node to work after I added the render_node 

folder to my File prefs. I found some errors in your "sprintf" usage 

for making paths - spaces in the name will mess it up, and probably 

I've been grappling with a lot of the issues this patch tackles, so I'm 

grateful for your post! I'll give it a shot on windows later. My 

partner Jay has been having trouble on a Windows laptop (X300-based 

video card) getting my texture readback stuff to work properly. I am 

eager for him to try your patch out so I can find out if it's my code 

or his machine (I'm guessing it's the computer's fault...speaking of 

which - does anyone know a good source for 3rd party video card 

drivers? I had him update the drivers, but they are from Dell - the 

ATI ones didn't cooperate - and that didn't help the problem...)

Because this is sure to be a useful reference for a while for a lot of 

people, here is a contribution to sort out the file paths issues for 

Max and standalone usage. You can insert this into the render_node 

patch as you see fit, Randy, as you are the master keeper!

I was able to get the render node to work after I added the render_node 
folder to my File prefs. I found some errors in your "sprintf" usage 
for making paths - spaces in the name will mess it up, and probably 
cause filepath errors.

I've been grappling with a lot of the issues this patch tackles, so I'm 
grateful for your post!  I'll give it a shot on windows later.  My 
partner Jay has been having trouble on a Windows laptop (X300-based 
video card) getting my texture readback stuff to work properly.  I am 
eager for him to try your patch out so I can find out if it's my code 
or his machine (I'm guessing it's the computer's fault...speaking of 
which - does anyone know a good source for 3rd party video card 
drivers?  I had him update the drivers, but they are from Dell - the 
ATI ones didn't cooperate - and that didn't help the problem...)

Because this is sure to be a useful reference for a while for a lot of 
people, here is a contribution to sort out the file paths issues for 
Max and standalone usage.  You can insert this into the render_node 
patch as you see fit, Randy, as you are the master keeper!

On Feb 23, 2006, at 8:29 AM, Thijs Koerselman wrote:

> Thanks a lot for sharing this! I hope I can figure out how to adapt 

> my patches to render_node. The test animation is working almost 

> without problems on windows too. The only thing I encountered is a 

> distortion in the output movie, similar to what I experience if I 

> use @doublebuffer 0 on a window in any jitter patch (this has 

> always been like that on my computer). Only now it's not visible in 

> the jit.window (when the patch is running or recording) but just 

> My animations use a lot of midi-triggered ramps and lfo's synced to 

> an external sequencer. I used to just divide the time constants by 

> 4 and run the render metro at fps/4 while recording to disk.

> Any thoughts on how to adapt this to your smpte based render? 

You don't really give me enough information to go on. But if you are 

using the fps/4 to insure that all your frames get recorded and not 

skipped when going to disk, this is what the nonrealtime more of 

render_node takes care of for you. You should just be able to remove 

that /4 stuff. When recording offline, render_node uses the 

Nonrealtime DSP driver, clocks everything from the DSP, and runs the 

time messages through jit.qfaker so that all messages will be allowed 

If you have other areas in your patch where you convert from signals 

to messages to trigger events, you can use the same switch logic to 

do the qfaker thing. there's an example in the "messages recorder" 

> Hi Randy,
>
> Thanks a lot for sharing this! I hope I can figure out how to adapt  
> my patches to render_node. The test animation is working almost  
> without problems on windows too. The only thing I encountered is a  
> distortion in the output movie, similar to what I experience if I  
> use @doublebuffer 0 on a window in any jitter patch (this has  
> always been like that on my computer). Only now it's not visible in  
> the  jit.window (when the patch is running or recording) but just  
> the output movie.
>
> My animations use a lot of midi-triggered ramps and lfo's synced to  
> an external sequencer. I used to just divide the time constants by  
> 4 and run the render metro at fps/4 while recording to disk.
>
> Any thoughts on how to adapt this to your smpte based render?  
> Thanks again.

You don't really give me enough information to go on.  But if you are  
using the fps/4 to insure that all your frames get recorded and not  
skipped when going to disk, this is what the nonrealtime more of  
render_node takes care of for you.  You should just be able to remove  
that /4 stuff.  When recording offline, render_node uses the  
Nonrealtime DSP driver, clocks everything from the DSP, and runs the  
time messages through jit.qfaker so that all messages will be allowed  
to complete before the next time tick.

If you have other areas in your patch where you convert from signals  
to messages to trigger events, you can use the same switch logic to  
do the qfaker thing.  there's an example in the "messages recorder"  
section of the "...test_pattern" patch.

On Feb 23, 2006, at 9:31 AM, Peter Nyboer wrote:

> I was able to get the render node to work after I added the 

> render_node folder to my File prefs. I found some errors in your 

> "sprintf" usage for making paths - spaces in the name will mess it 

> up, and probably cause filepath errors.

Thanks a lot Peter! I incorporated your paths fix and it works a charm.

I had to give up and put my jsui script in the same directory as the 

patcher. I couldn't find a way to load the jsui script dynamically 

without getting en error message at startup when its file attribute 

is set to something nonexistent. I wonder if you've handled this too?

Anyway, there's a new version of render_node out now, 0.51. It 

solves these path problems and has another minor fix or two. Now the 

timeline is initialized correctly to loop the whole file. The help 

file mentions that the keyboard commands space (start/stop) and esc 

> I was able to get the render node to work after I added the  
> render_node folder to my File prefs. I found some errors in your  
> "sprintf" usage for making paths - spaces in the name will mess it  
> up, and probably cause filepath errors.

Thanks a lot Peter!  I incorporated your paths fix and it works a charm.

I had to give up and put my jsui script in the same directory as the  
patcher.  I couldn't find a way to load the jsui script dynamically  
without getting en error message at startup when its file attribute  
is set to something nonexistent.  I wonder if you've handled this too?

Anyway, there's a new version of render_node out now, 0.51.  It  
solves these path problems and has another minor fix or two.  Now the  
timeline is initialized correctly to loop the whole file.  The help  
file mentions that the keyboard commands space (start/stop) and esc  
(fullscreen) are enabled by default.

let me say, Thanks Randy! You have some great patches on your site,

However, I wonder if you or others here may be able to get me past this issue.

I am using a patch driven by midi events. I can use the MIDI files in

Max, but what is the best way, with say a "seq" object to bang through

Midi files? Id like to load in my files, and then have then drive at

the same speed as they did originally, around 103 bpm.

Any suggestions on how to work with the Worldtime or Phasor to make

let me say, Thanks Randy!  You have some great patches on your site,
and this is sure one of them.

I am using a patch driven by midi events.  I can use the MIDI files in
Max, but what is the best way, with say a "seq" object to bang through
Midi files?  Id like to load in my files, and then have then drive at
the same speed as they did originally, around 103 bpm.

Any suggestions on how to work with the Worldtime or Phasor to make
the seq object bangable?

The "messages_recorder" subpatch of the test_pattern shows how to use 

seq~ synched with the recorder. You can play your MIDI data into 

seq~ (from seq or wherever) and then play it back at the original speed.

Possibly seq (sans ~) would work with the nonrealtime driver/qfaker 

setup I am using, but I wouldn't assume anything until trying it 

out. If you wanted to use seq, you would have to hook up a few of 

the globals from the transport in order to get the scrubbing and such 

The "messages_recorder" subpatch of the test_pattern shows how to use  
seq~ synched with the recorder.  You can play your MIDI data into  
seq~ (from seq or wherever) and then play it back at the original speed.

Possibly seq (sans ~) would work with the nonrealtime driver/qfaker  
setup I am using, but I wouldn't assume anything until trying it  
out.  If you wanted to use seq, you would have to hook up a few of  
the globals from the transport in order to get the scrubbing and such  
to work.

But wont playing it back at original speed screw with the timing once

This is where I get confused. I dont understand how the Midi file is

supposed to playback and sync with the video...

But wont playing it back at original speed screw with the timing once
the frame by frame capture is going?

This is where I get confused.  I dont understand how the Midi file is
supposed to playback and sync with the video...

seq~ is driven by a phasor which represents "world time" regardless 

of whether the animation is running in real time or offline.

seq~ is driven by a phasor which represents "world time" regardless  
of whether the animation is running in real time or offline.

You the man, I'll try it all when I get home.

Perhaps this will do what you need (from the Max manual)...

After seq has received a start -1 message, it waits for tick messages to

advance its clock. In order to play the sequence at its original recorded

tempo, seq must receive 48 tick messages per second. This is equivalent to

24 ticks per quarter note (the standard for a MIDI Clock message) at a tempo

of120MM. By using tick messages to advance the sequencer, you can vary the

tempo of playback or synchronize seq with another timing source (such as

tick 
After seq has received a start -1 message, it waits for tick messages to
advance its clock. In order to play the sequence at its original recorded
tempo, seq must receive 48 tick messages per second. This is equivalent to
24 ticks per quarter note (the standard for a MIDI Clock message) at a tempo
of120MM. By using tick messages to advance the sequencer, you can vary the
tempo of playback or synchronize seq with another timing source (such as
incoming MIDI Clock messages).

Cheers,
Gary Lee Nelson
TIMARA Department
Oberlin College
www.timara.oberlin.edu/GaryLeeNelson


I have a related problem. I am using a frame-based sequencing method. I

found a place to get running frame numbers inRender_node by dividing the

world time by the appropriate value. This works great in nonreal mode but

in realtime, it seems to skip frame numbers. I tried watching for a

particular frame number and print a bang when it arrived but it was accurate

only 50% of the time. Is there a better way?

I have a related problem.  I am using a frame-based sequencing method.  I
found a place to get running frame numbers inRender_node by dividing the
world time by the appropriate value.  This works great in nonreal mode but
in realtime, it seems to skip frame numbers.  I tried watching for a
particular frame number and print a bang when it arrived but it was accurate
only 50% of the time.  Is there a better way?

On Feb 27, 2006, at 3:49 PM, Gary Lee Nelson wrote:

> I have a related problem. I am using a frame-based sequencing 

> found a place to get running frame numbers inRender_node by 

> world time by the appropriate value. This works great in nonreal 

> in realtime, it seems to skip frame numbers. I tried watching for a

Render_node for Jitter.