frame optimization through ballistic precomputation

Given that properly tuned scanners at, say 30k using the ILDA test frame, have an approximately equal impulse response, it follows logically that point drawing (and reduction) optimizations could be applied, especially to fine detail and small movements, that make use of points that are never reached. This concept is nothing new to the laser show industry, frames have been produced and tweaked manually that rely on this.

In the open-hardware software arena there are products such as anarchy that specialize in automatic optimization. Do these software optimization routines make use of the ballistic point-pulling technique in order to increase framerate?

I am thinking of implementing this in some software in the future and would like some feedback.. would you consider it to be 'too hard' on the scanners?

To the best of my knowedge, Anarchy actually does the opposite of what you're describing. That is, the automatic point optomization routine will *add* points to smooth things out. Thus, if you optimize the ILDA test pattern, you'll end up with a dodecagon outside the square when you scan it.

I'm assuming that you're thinking about implementing some kind of "pulled-points logic" in your software, where the ballistic arc that the scanner would take if fed a set of widely-spaced points could be pre-calculated, and then the points of the file adjusted to give the desired curve with fewer points... That would be quite interesting if you could pull it off!

It could be harmful for the scanners, however. The ILDA test pattern is OK when you scan it at 8 degrees, but if you max out your scanners, it's no longer OK. The same thing would apply to a lesser extent with the images this new logic could produce. My suggestion would be to start out very conservative and then move up from there.

Have you already thought about how to pre-calculate the scanner response? (Or did you plan to "calibrate" the the software to the scanner response based on a series of test images?)

Adam

Yes, that's what I was thinking, adding this for smaller jumps and details so that it would not be harmful. Ideally, response from all properly tuned scanners would be the same, but I would implement a few test images to calibrate the algorithm parameters on a per-scanner basis.
Another interesting aspect is that the original vector oriented 'intent' of the optimized ilda file could be reversed into a proper-looking frame on a computer, given the right algorithm and parameters. This would help to make ballistic optimized frames portable across platforms and scanner types.

I have been thinking of optimization lately, as well. I had a different idea but it could be applied to what you are proposing. I was thinking that if I created a utility that displays points, lines, and angles of different sizes I could display them on my scanners at different speeds and then figure out a formula that would give me the best blanking based on distance, speed, and angle. This would allow for adding the correct number of anchor points, specifying the correct color shift, etc for any speed or step distance. I suppose you could somehow use this information to determine how hard to pull points as well.

Sounds like a cool idea, Doc. Unfortunately, it puts all the weight on your shoulders to develop the logic!

Still, I'd love to hear more about it if you decide to move forward with this...

Adam

Just thinking out loud but, for a perfect square, what if you actually let it overshoot, and use blanking to make it perfect.
ex: you want a square, but you actually draw a '#' kinda pattern. You draw the 2 vertical lines first and the 2 horizontal next, and you use blanking to get rid of the 8 little overshoots ?

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Originally Posted by carmangary

I have been thinking of optimization lately, as well. I had a different idea but it could be applied to what you are proposing. I was thinking that if I created a utility that displays points, lines, and angles of different sizes I could display them on my scanners at different speeds and then figure out a formula that would give me the best blanking based on distance, speed, and angle. This would allow for adding the correct number of anchor points, specifying the correct color shift, etc for any speed or step distance. I suppose you could somehow use this information to determine how hard to pull points as well.

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Yes, a combination of ballistic point pulling and velocity based laser modulation adjustment could be close to an ideal optimization set. If we could get this in code, along with the reverse calculations it could provide a nice boost to the frame complexity achievable by common scanners.

Agreed. I would like to someday get away from having to specify images as a set of points and only as a series of segments, beziers, and shapes and then let the software figure out how to draw it based on the characteristics of your scanners. And, your scanner characteristics coud be easily discovered by a wizard that simply shows pictures and asks you to choose the best one as it learns... the same as how an eye doctor uses many different images during your eye test.

This is pretty basic stuff, engineers in the electrical field calculate transfer functions and compensate for non-ideal impulse response every day. There are only a few variables to look at, a wizard would not have to be too involved. Frankly I'm suprised this hasn't already been implemented in everything, including a section for parameters in the ILDA format. Either there aren't enough engineers in the laser show industry or we are overlooking a fundamental flaw.. ?

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Originally Posted by carmangary

Agreed. I would like to someday get away from having to specify images as a set of points and only as a series of segments, beziers, and shapes and then let the software figure out how to draw it based on the characteristics of your scanners. And, your scanner characteristics coud be easily discovered by a wizard that simply shows pictures and asks you to choose the best one as it learns... the same as how an eye doctor uses many different images during your eye test.

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DocL, please send me a email so I can send you a small attachment you might find interesting.

I also have the equation of state for a galvo scanner, I will scan it in for you as a JPeg this evening. I would caution all of you that your neglecting hysteresis in the bearing friction, and that DSP scanner amps have only made the civilian market in the last 3 years.

Another technique is to accelerate the scanner to a position P, then apply a precise timed pulse of 1/2 the magnitude and the opposite phase at a time Tau later, thus slamming on the brakes so to speak and eliminating the need for damping.

I also caution you that good laser artists, in order to keep overall intensity even in large complex animations, often add parts of the image that will appear in the future, as blanked points, so the scanner scans them, thus there is no popping in the graphics or dimming as the animation changes.

Steve

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Originally Posted by mixedgas

Doc, please send me a email so I can send you a small attachment you might find interesting.

I also have the equation of state for a galvo scanner, I will scan it in for you as a JPeg this evening. I would caution all of you that your neglecting hysteresis in the bearing friction, and that DSP scanner amps have only made the civilian market in the last 3 years.

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true, DSP scanner amps could do all of this internally, negating the need for the software to do it. That technology will likely take a while to become affordable, no?

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Another technique is to accelerate the scanner to a position P, then apply a precise timed pulse of 1/2 the magnitude and the opposite phase at a time Tau later, thus slamming on the brakes so to speak and eliminating the need for damping.

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Isn't this close to what damping already does, but in a linear way not a pulsed way

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Originally Posted by drlava

Frankly I'm suprised this hasn't already been implemented in everything, including a section for parameters in the ILDA format. Either there aren't enough engineers in the laser show industry or we are overlooking a fundamental flaw.. ?

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Hehe. We have done a bit of work in this area ourselves, and if you take a look in some articles I wrote for The Laserist magazine around 15 years ago, you will see a discussion vaguely along these lines and how to do it pretty easily.

The "fundamental flaw" you are looking for is the assumption that the impulse response of all 30K scanners is the same, but this is not the case.

Think of it this way. Lets say you had a lot of people, all with 30K "filters", but each person implemented their filter with a different number of stages, and with different rail voltages at each stage. The analogy hopefully paints the picture that yes, for very tiny signals, perhaps of a few degrees, the impulse response is the same. But outside of that realm, it becomes more and more of a crap shoot as to whether or not scanners will actually be able to draw the images that are intended. With the wide variety of scanners out there, all claiming to be "30K" but being drastically different in nature, well, it is not possible to provide a meaningful improvement and also at the same time be compatible with the meriad of scanners that are in the field right now. There are other implications to this as well, but to discuss them would seem to take this off-topic...

But anyway, if you want to explore this go right ahead. We have already done the work in this area and we already have our own conclusions. But a good professor of mine used to say "student teach thyself"! Sometimes the best way to learn about a problem is by doing work on it. Who knows, maybe you will find some magical solution that will solve what I see as "compatibility" problems, and also the "other implications" that I aluded to above.

Bill

[QUOTE=Pangolin;66347]Hehe. We have done a bit of work in this area ourselves, and if you take a look in some articles I wrote for The Laserist magazine around 15 years ago, you will see a discussion vaguely along these lines and how to do it pretty easily.

The "fundamental flaw" you are looking for is the assumption that the impulse response of all 30K scanners is the same, but this is not the case.

Ah, the pe....
I'll save you the trouble of looking that up when James gets us together this week, I'll bring a copy.

Steve

Ok, cool. As we stated earlier, scanners all won't be the same so some tuning will be needed, the parameters of which can be stored. But it sounds like they were just TOO different for Bill to think this technique was justified in a general sense. Although, this line of thinking has brought up some other ideas which hopefully will be implemented in some upcoming sofware soon... :)

Hi guys,

Just a few more points:

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Originally Posted by carmangary

Agreed. I would like to someday get away from having to specify images as a set of points and only as a series of segments, beziers, and shapes and then let the software figure out how to draw it based on the characteristics of your scanners.

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This part is already working in our relatively new software like LC-MAX, LC-FLASH, LC-4D, and a few others, the user really doesn't need to specify points and such. The input is there, and the software automatically figures out how to control the scanner to achieve, at least what we believe is optimal results. There is some adjustability available to the user, but the default parameters we have chosen work really well.

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Originally Posted by drlava

Ok, cool. As we stated earlier, scanners all won't be the same so some tuning will be needed, the parameters of which can be stored. But it sounds like they were just TOO different for Bill to think this technique was justified in a general sense.

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Well, it is really a matter of:
1. Exactly how much faster could you get the scanning, and;
2. Exactly how much variability is there.

Regarding the first point, within my article years ago, I stated that you could only get around a 50% increase in scanning speed. Then a few years after I wrote that article Bruce Rohr said the same thing in a speach at ILDA. And more recently, I have seen this same 50% estimate in servo books. Now, 50% might seem like a lot, but it really isn't that much... Also, this 50% was a whole lot easier to get with the G-120 which (because of common servo topologies used) executed all steps in roughly the same amount of time. This is no longer the case with 6800 and more recent scanners.

And lastly, once you accomplish this, you will see other "artifacts" that I won't mention here. (You'll just have to spend your time doing it, and then you will see them.) These are "artifacts" of the solution, not "problems" that could be solved with more work.

With regards to the second point, we have found that, in the field, there is HUGE variability between what all of our users have (despite the fact that everyone thinks they have 30K scanners), so we purposely make sacrifices in certain areas of *absolute performance* so that ordinary users with ordinary equipment will be able to display good looking imagery.

As one example of this, we do not supply any raster frames that do bi-directional raster, only uni-directional. You could get bi-directional to work, but it won't look good UNLESS everything is really perfect, and I mean everything. The linarity, acceleration and deceleration characteristics, and a lot of other factors have got to be the same in both directions, and also the color shift really has got to be tuned perfectly for a bi-directional raster to look right. Otherwise you get what looks like a "comb" effect in some parts, or all parts of the image. LOBO uses bi-directional rasters, but they have control over every part of the process. They make their own software, their own scanner amps, their own mirrors, etc. And yet, you can even see flaws in their rasters in their rasters if you look closely enough. So we only supply uni-directional rasters with our stock imagery because because almost nothing needs to be working correctly for you to get half-way-decent looking imagery. About the worst that can happen is that the entire image is shifted, but it still looks OK with no "comb" effect.

So, since we have a large user base and we want to have a good "out of the box experience", we sacrifice *absolute performance* in some respects, in favor of the darn thing just working pretty well for most people.

So sure, it is possible to make a system with a wizard that figures out this and that about the scanners, and then can adjust the output in some way to get a more optimal scanning. But our experience shows that the increase would not be "meaningful". And that, even if everyone was using exactly the same equipment, the "artifacts" that result from strongly applying the approach are not worth it.

It's easier to get a speed increase with different scanners or a different servo technique, and this also gives none of the "artifacts" of the point-pulling.

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Originally Posted by drlava

Although, this line of thinking has brought up some other ideas which hopefully will be implemented in some upcoming sofware soon... :)

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Great! That's what learning is all about!

Bill

Bill, why don't you describe what the artifacts were and help with the problem? We already know that Pangolin has already done everything we are doing many years ago. So why not help us out?

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Originally Posted by carmangary

Bill, why don't you describe what the artifacts were and help with the problem? We already know that Pangolin has already done everything we are doing many years ago. So why not help us out?

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If you're going to continue with the "chip on your shoulder" attitude, why should he bother helping you?

Seriously - you ask Bill for information, he gives it to you, then you find some reason to thumb your nose at him. This pattern has repeated itself more than a few times. If I were Bill, at this point I'd have to seriously question your motives. Sure, he likes to help the community, but when you're openly hostile, why in the world would he feel obligated to deal with you?

If you had bothered to attend one of the laser enthusiast meetings, you could have seen the raster images in person. It would have been a simple matter to adjust the color shift to show you how that can alter the image, and you would then understand why a bi-directional raster would give you comb distortion. (For that matter, if you had visited the Pangolin office when you were in Florida, Bill could have shown you this in person and in much greater detail.)

Likewise, if you had seen one of the scanner tuning seminars, you'd understand some of the other problems that can crop up when you assume that both scanners will always be running at the same speed (which they often aren't when you get close to their performance limits). I don't claim to understand the entire problem, but I know that I've got a better understanding of scanners as a result of being there.

But that's right... You decided that you didn't want anything to do with Pangolin... I quote:

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Originally Posted by carmangary

Yea, you were helpful with the ILDA format stuff and I thought you were a stand up guy for helping me out. But, since then, other stuff has happened, which lead me to canceling my trip to visit Pangolin when I was out in Florida or ever having any of your products in my possession.

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So why, again, are you asking for his help? Especially when you find him so repulsive that you've proclaimed in public that you'll never allow yourself to posses any of his products?

Your decision to cancel your trip seems rather foolish, given everything you stood to gain from it. And here you are, demanding more help from the very person you claim to dislike. :confused:

I just don't get it...

Adam

I was seriously not asking for help. You kind of missed the point. I'm not going to get into it publicly, though.

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Originally Posted by carmangary

Agreed. I would like to someday get away from having to specify images as a set of points and only as a series of segments, beziers, and shapes and then let the software figure out how to draw it based on the characteristics of your scanners..

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Exactly how I like to do it - actually it was one of my first goals when I started coding. All the `art' in Laseroids, Lasertennis and even the 3D grid are all defined in SVG, thus in beziers. I never touched the point data manually although I stored the graphics in ILDA format in order to safe the work of the conversion algorithm after tweaking the parameters.
Taking the next step will prove to be a lot of work and seems Utopian from what I learned about current laser scanning systems. To do it properly one would need the feedback signal from the scanners.

Mixedgas:
I actually tried the "braking peak method" you describe when I was still toying with homebuilt openloop scanners.
It worked for a large part but getting it right proved near impossible due to severe riming issues with the parallel port and windows. Implementing this with modern DACs seems not feasible either because the Tau cannot be chosen as there is a fixed timing between the points.
I got started with it because my scanners had severe damping issues.
Some of the results I got are in this gallery (second half): http://picasaweb.google.com/DrZoof/HowItStarted#
You can find a drawing showing the idea and then results with and without the compensation.

I think that if the characteristics of the scanners are known well enough, you can do either or or both of the following:

(1) Be able slow the galvos down enough by speed control, anchor points, etc so that things are drawn correctly.
(2) Be able to compute "pulled" paths that in reality are displayed as you want tem to be. (ie the circle in the ILDA square trick).

#2 is too much for my brain so I plan on just going after #1. After that I'll probably change Spaghetti to also support a new format of laser drawings (non-ILDA) that either I will create alone or with anyone who is interested. They already do exist, though. Moncha creates this type of drawing in their drawing program. Once you are done with it you export it to ILDA. I want to just bypass the ILDA file step. This is one reason that I don't think that WAV files will be useful in the future as James predicts. They are still point based and have no notions of curves, circles, etc.

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Originally Posted by carmangary

I think that if the characteristics of the scanners are known well enough, you can do either or or both of the following:

(1) Be able slow the galvos down enough by speed control, anchor points, etc so that things are drawn correctly.
(2) Be able to compute "pulled" paths that in reality are displayed as you want tem to be. (ie the circle in the ILDA square trick).

#2 is too much for my brain so I plan on just going after #1. After that I'll probably change Spaghetti to also support a new format of laser drawings (non-ILDA) that either I will create alone or with anyone who is interested. They already do exist, though. Moncha creates this type of drawing in their drawing program. Once you are done with it you export it to ILDA. I want to just bypass the ILDA file step. This is one reason that I don't think that WAV files will be useful in the future as James predicts. They are still point based and have no notions of curves, circles, etc.

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So basically what you want to do is define the geometry of the art and let the computer figure out how to draw it. The file format you want to define would then be geometry based, e.g., spline, beziers, primitives, etc. Is there any laser-application specific information you want to add to the file?

Yes, that is basically what I want to do. I don't think there has to be anything laser specific in the file itself but there would probably be limitations imposed based on the fact that the drawing has to be displayable with a laser scanner. And, although I can't think of anything off of the top of my head, there may be some features desired that are more relevant to laser display than to just normal drawing.

So, whatever the format ends up looking like, it would be more suitable to defining laser pictures than defining fonts or CAD drawings. It would also hopefully be simple enough so that it could be rendered in real time.

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Originally Posted by carmangary

Yes, that is basically what I want to do. I don't think there has to be anything laser specific in the file itself but there would probably be limitations imposed based on the fact that the drawing has to be displayable with a laser scanner. And, although I can't think of anything off of the top of my head, there may be some features desired that are more relevant to laser display than to just normal drawing.

So, whatever the format ends up looking like, it would be more suitable to defining laser pictures than defining fonts or CAD drawings. It would also hopefully be simple enough so that it could be rendered in real time.

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I still think Inkscape - SVG is an excellent candidate. As far as I can see now there are two nice-to-haves missing: color gradient along the path in addition to linear and radial color gradients. And it only does 2D.
A big plus is that is comes with a great drawing package for free :D
www.inkscape.org

Perhaps. I don't know anything about it. Is the file format documented? I'm definitely not opposed to using anything already built as long as it is a clean solution.

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Originally Posted by carmangary

Bill, why don't you describe what the artifacts were and help with the problem?

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In very broad terms, the "artifacts" are related to brightness variations, and timing. The "timing" part is REALLY subtle and possibly would not be noticed until the very end of any such developments. There is another "artifact" that, as an image is being zoomed up, it must certainly change using this method, and certain changes will be localized and thus, become noticeable.

The brightness variations may (possibly) be compensated by simply dimming other parts of the image whose brightest was not affected. BUT, as I wrote in another post about lighting, shading, shadows and textures, people pay so damn much for laser light, it's a shame to have to waste any at all...

I can demonstrate all of this if you are interested, and if you come to Pangolin...

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Originally Posted by carmangary

I'm not going to get into it publicly, though.

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Really Gary, I am not sure what I have "done", and would be happy to get into a discussion privately. I have reached out to you privately but... nothing. I suppose no healing can happen without discussion. Since I have reached out and you have not responded, I guess you are not interested in healing...

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Originally Posted by carmangary

We already know that Pangolin has already done everything we are doing many years ago. So why not help us out?

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No, I would never claim that Pangolin has done everything, or that we have nothing to learn. Nor would I claim that nobody here is doing anything new here on PL. I would only claim to have expertise in the area (just as a related testament, our software has won more awards than I can count -- and not only that, but I have designed award-winning servos as well, so I know this subject matter) and would want to help out in any way that I can. It could be that the discussion ends up in territory that is ultimately successful, for example with what Dr. Lava says he discovered most recently.

Nevertheless, yes, as Buffo wrote, there are people on PL who seem to have a big chip on their shoulders. Really most of the people are great, but there are a few who really ruin it for everyone else.

Within the last few days, I have started wondering what the hell I am doing contributing to this forum in the first place, when we have a forum of our own.

Up until now, I have considered PL to be a great gathering place and have been happy to comment non issues that are Pangolin- and non-Pangolin-related.

I guess for the more important topics, especially where I detect that Lehman-izing might take place, I will make a post and link them onto the Pangolin forum, where things seems to be more mellow and it's more of a "just the facts" type forum. That way people could get the benefit of the discussion, without the distraction of attitude...

I appreciate the approach that Dr. Lava and Zoof have taken. I don't know them, and don't know how "professional" they are in terms of their career, but I do know that they have acted with integrity, and have kept negative attitude out of their posts. Maybe these guys should give lessons or something ...

Bill

Well, lets just bury the hatchet. There really is no reason to worry about water under the bridge. I apologize for being a jerk to you and mean that sincerely.

Hi Adam,

Just one quick point.

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Originally Posted by buffo

...to posses any of his products

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They're not "my" products. They are Pangolin products. Pangolin has lots of people who contribute to the products. Then, when they get into the hands of others, they also contribute. Many times the contributions from people who don’t work at Pangolin (for example laser artists and programmers) winds up back into the Pangolin platform. It's a big happy (yes happy) family :D.

The problem with me is that I am not a sympathetic character. Basically responses you get from me are like a robot. You ask a question, you get an answer. Pretty much there is no emotion in it at all... I'm not going to bend over backwards and tell you how much I appreciate you or that you're doing a wonderful job. From me, you only get the facts.

Fortunately, there are lots of other people at Pangolin who are sympathetic characters. Basically, lots of other people at Pangolin who you can "love" if you want to. Hayden, as one example, takes a completely different approach and has a different kind of camaraderie here on PL (and in person). And Hayden's from Texas Gary. I am sure you would love him :D.

So I guess my point is, you don't have to love me personally. Certainly there is *someone* at Pangolin who you can love if you want to ...

Bill

I thought the brightness variations would be one of the issues you were talking about. These can't be completely compensated for in software because the variations (due to velocity change) can happen between points where software has no control. Another somewhat obvious drawback is that you can't have sharp corners without investing more points, thus somewhat defeating the purpose. For example, it's doubtful the tic tac toe approach to a square mentioned earlier would provide any speed gains after the points required to bring the galvos back around at each corner were added.

The other night I began building a matlab simulink model of the galvo/scanner system which looks a lot like figure 5 from this excellent page:
http://elm-chan.org/works/vlp/report_e.html
however the galvo model is missing the mechanical resonant properties that make the HFD relevant. I was thinking of adding a short delay function before the second pole in the galvo to simulate this in a simple way, but am open to other suggestions.

P.S. looking forward to reading that article, mixedgas!

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Originally Posted by Pangolin

Hi Adam,
Just one quick point. They're not "my" products. They are Pangolin products.

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Hi Bill;

Sorry about that... I wasn't trying to imply that you did all the work with that remark, I was simply paraphrasing Carmangary's earlier message.

It's a good point you make, however, regarding the cooperative nature surrounding many of the Pangolin products. An excellent example is Justin Frankel's Winamp Laser Visualizer plug-in. That's a very cool tool that came not from Pangolin, and not from you personally either, but rather from a Pangolin user who figured out how to make it work.

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The problem with me is that I am not a sympathetic character. Basically responses you get from me are like a robot. You ask a question, you get an answer. Pretty much there is no emotion in it at all... I'm not going to bend over backwards and tell you how much I appreciate you or that you're doing a wonderful job. From me, you only get the facts.

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"Not a sympathetic character"... That's an interesting point. I seem to recall that you and I got off to a rocky start several years ago over something very similar to that. But after we met in person, I realized that I had taken your mater-of-fact posts waaaaay too personally. I believe I was eating crow for about a month after that. :o

But yeah, I think some people can take that the wrong way. (I sure did.) Nevertheless, I am glad that you are still here and still providing answers to questions. Emotionless or not, the answers are *very* much appreciated.

Adam

Hey Bill,

It's kinda weird but, If I had any troubles with the FB3, my first goal was to look on photonlexicon. Second came pangolin's forum.

I think my reason was because this forum seemed more alive (counting the nr of posts). Technically, you also posted a lot more in photonlexicon than in pangolinforum :p

I have some experience setting up forums and all, and usually, these are the problems:

• professional forums have usually less posts then amateur forums because professional users tend to call / email for support, in stead of posting something, and waiting for a reaction.
• you need critical mass in users and posts per user to keep a forum alive. However, this also means you are gonna have a crapload of posts that have nothing to do with the subject (hmm, even my very own post applies..hehe). This can be solved with a some moderation, but that takes time and money.
• What we see often is that a professional forum doesn't take off, and the knowledge from the forum ultimatly changes into a wiki/faq..

Ultimately, I would do just what you were doing all along. It's quite rare that a professional company releases so much of their knowledge into the public. And speaking as your customer (FB3), that conviced me to go for the FB3 and not another DAC..

Just my 0.02..

Btw, I just found the livequick tutorials on pangolin forum!!! AWESOME!!!

I don't care what other people do but I decided I would rather have my questions and convesation about Spaghetti on my own web space so that the info is easily found by others and in one place instead of scattered about. So, I try to direct people there. I also do it as a courtesy to those who don't care about Spaghetti on here so that they don't have to read about it.

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Originally Posted by carmangary

I decided I would rather have my questions and convesation about Spaghetti on my own web space so that the info is easily found by others and in one place instead of scattered about.

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Hi Gary;

That's a good point. It does make it easier to track revisions, look for solutions, and in general get help from the community when everything is in one place. It also makes it easier for the person maintaining the site, because usually you only have to answer a question once.

However, it's hard to direct traffic from PL to the google groups unless you monitor PL religiously. And that cuts into the time advantage a bit, no?

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I also do it as a courtesy to those who don't care about Spaghetti on here so that they don't have to read about it.

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Well, some people may not be following your project on a daily basis via google groups, but might still appreciate an update every now and then. And I think you'll get a better draw (that is, more new users) by posting about your project here. I don't think your posts about Spaghetti are cluttering up anything here.

Realistically, I think a balance between the two is probably the ideal case. Frequent updates on Google Groups, and periodic updates/announcements here on PL. As for support questions, it's your call as to where you want to answer them, but I don't think anyone will begrude you posting your answers in both places.

Just my $.02

Adam

I certainly won't totally ignore questions or refuse to talk about Spaghetti on here if it comes up.