Laser Projector (Red, Green, Purple) "Laser 3D Party Light" from Spencer's

[DogP]

DogP, Nice show!

Thanks! LaserBoy did a good chunk of the work for me.

DogP

[james]

I noticed a lot of familiar effects!

Did you sequence all the frames together into one big ILDA file using LaserBoy?

It's pretty amazing what you got out of that not so fantastic projector!

You should think about building a LaserBoy DAC!

James.

[DogP]

Did you sequence all the frames together into one big ILDA file using LaserBoy?

No... I used their .prg, because I changed the DAC sample rate on a few of the files (15K looks good for the most part, but was too flickery on some, so I bumped up to 20K on a few). A slight pause between animations isn't a big deal to me (the delay on single frame repeats is bad, but I didn't have any).

You should think about building a LaserBoy DAC!

Yep... it's in the plans. I talked about it in post 122.



DogP

[tribble]

Yep... apparently the MCU isn't smart enough to anticipate what's happening on the .prg. Though, just a suggestion... static frames are kinda boring - LaserBoy has some really cool effects. If you do output -> ild -> ild generate & save frame effect, there's a lot of options. In my animation: http://www.youtube.com/watch?v=Drd8kk51vmM , at 0:45, I did the "rotate" effect (saves as rotate.ild), and did a "break" with the last frame. And at 3:23, I did the save frame _SET_ effect, with a blend. And I used "move_l2r" a couple times too.

Thanks for the leads! I've been playing with the frame effects; some of them are really fun. I've noticed some of them behave differently if there are single or multiple segments in the frame. I've also noticed some of them don't work with the Spencer projector without further processing. Good fun.

What James said is correct (of course), but another thing to do is set the bit resolution. The DAC is only 8 bits, so if you have a lot of points close together, the .ild file tells the DAC to generate those points, but they all end up being the same point, due to the resolution. First, in the 't' menu, it tells how many bits to mask - set x and y to 8, and the rest don't really matter. In the 'h' menu, do <shift>+8 to impose bit resolution on all the frames. Then I usually minimize all (<shift>+i). That should get rid of any points that landed on top of each other. Then I optimize.

I tried that and I'm not sure it's improvement for the test frames I'm working with... mostly hypocycloids and hypotrochoids. I'll need to do some before-and-after shots to see how things change.

Have you done anything with the palette masking? I've had mixed results resetting the palettes of imported files to play on the Spencer projector. For example, I extracted James' snowman frame and applied the rotate effect, and I can hear the scanners drawing it, but the lasers never turn on. I have been able to re-map some other imported files successfully, but not all of them.

[james]

It is likely that this DAC cannot read ILDA file section 2. That is the palette. From what I gather, it can only read ILDA section 0 and assume that the palette is the standard 63 colors.

If the lasers are TTL modulated, then there are only 7 colors.

palette = Default_

index 0 ~ 255, 0, 0 = red
index 16 ~ 255, 255, 0 = yellow
index 24 ~ 0, 255, 0 = green
index 31 ~ 0, 255, 224 = cyan (this is as close as it gets, should be 0, 255, 255)
index 40 ~ 0, 0, 255 = blue
index 47 ~ 255, 0, 255 = magenta
index 57 ~ 255, 255, 255 = white

Are you making the hypocycloids and hypotrochoids in LaserBoy?

DogP, are you sure that thing has 6 discrete channels of DAC?

[tribble]

Are you making the hypocycloids and hypotrochoids in LaserBoy?

Yes, with some help from Excel to calculate the appropriate values for rational, closed figures when I want them. Sometimes it's fun to just let them never close and let persistence of vision provide an interesting display.

[james]

If you look at all the list of strange words in menu "m render segments by coordinates", you can find all of them in wiki!

The pages they have for them explain them quite well with visual animations and formulae for common forms.

http://en.wikipedia.org/wiki/Rhodonea_curve
http://en.wikipedia.org/wiki/Epicycloid
http://en.wikipedia.org/wiki/Epitrochoid
http://en.wikipedia.org/wiki/Hypocycloid
http://en.wikipedia.org/wiki/Hypotrochoid
http://en.wikipedia.org/wiki/Lissajous_curve

LaserBoy figures out how many times it needs to go around the circle to complete the figure.

When it asks for units, they are relative to short integer space, ie: -32767 to +32767.

James.

[DogP]

I tried that and I'm not sure it's improvement for the test frames I'm working with

It may not be very noticeable, but I find that it usually reduces the minimized point count at least by a little bit (of course optimizing the file puts a lot of points back in). I figure I might as well do it during processing, since the projector is gonna do it when it reads the file anyway. Where it really makes a difference is on scaled art, where there's a ton of detail on the full thing, but if you simply scale it to be small, the .ild file still holds the full detail, except that the projector can't reproduce it (there's no point in telling it to draw the same dot 1000 times). It's also nice that it shows you what it's actually gonna do (though sharp edges get smoothed by the projector). I've also used it as a crude way to optimize. My bullet bill animation had too many points (was flickery), so I reduced it to 7 bits. That made the animation a little bit blocky... but it got rid of a bunch of points, especially around the curves, and it turned out looking good.

For example, I extracted James' snowman frame and applied the rotate effect, and I can hear the scanners drawing it, but the lasers never turn on. I have been able to re-map some other imported files successfully, but not all of them.

I'm not sure if this is the problem you're having, but in the 'p' menu, I make sure the default palette is selected, and do <shift>+b to set the colors to the best match with that palette. I had to do that for all my text imports and it worked perfectly... so if you can't get it to work from ild to ild, try saving as a text file and opening the text file and saving as an ild (and maybe delete the palette section from the text file).

DogP, are you sure that thing has 6 discrete channels of DAC?

Yep... it's got a CM6206-LX chipset (6 channels). It's got a few audio amplifiers on the other side of the board which are wasted... but it's nice that it's so tiny without all that extra stuff that most USB sound cards have (connectors, electolytic caps, etc). The headphones themselves have 3 speakers in each ear for surround sound, but they pretty much suck as headphones (they are small and hardly block any outside sound).

DogP

[james]

That's pretty freakin' tiny. Was it easy to tap the DAC channels?

[DogP]

That's pretty freakin' tiny. Was it easy to tap the DAC channels?

I haven't done it yet... I got it right before I was heading out of town. The worst case is connecting directly to the QFP pins, which wouldn't be too bad... but I'm sure there are caps to AC couple the signal, which I can either connect the wires directly to those pads, or short those caps and connect further downstream.

DogP