frame optimization through ballistic precomputation

[Zoof]

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.

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?

[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.

[Zoof]

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.

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
www.inkscape.org

[carmangary]

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.

[Pangolin]

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

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...

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

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...

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

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

[carmangary]

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.

[Pangolin]

Hi Adam,

Just one quick point.

...to posses any of his products

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 .

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 .

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

[drlava]

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!

[buffo]

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

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.

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.

"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.

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

[highvolt]

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

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!!!