Skip to content

Reference Manual

Shapechanger

Technical documentation, setup guidance, and patching workflows.

← Back to Shapechanger overview

Shapechanger Archive

Archived community reference. This page preserves the official LZX Community forum thread for Shapechanger inside the new documentation site.

Additional related discussions are included below.

Open original thread

Shapechanger is our most ambitious analog computing module to date. Designed to take two continuous input voltages representing X and Y points on a display, Shapechanger processes the size, width, height, aspect ratio, symmetry, and curve of a resulting quadrilateral figure.

Specifications

  • Width, 16HP
  • Mounting Depth, 45mm
  • Power +12V @ 220mA
  • Power -12V @ 220mA

User Reference

Videos

Patching Tips

  • Use mults to send the same modulation source to multiple VC inputs at once. Use mixer modules (like Passage or Bridge) to mix together many modulation sources.
  • Try feedback of the horizontal and vertical outputs back to the VC inputs.
  • Try patching multiple Shapechanger modules in parallel, and use a keyer module like Doorway to composite the two resulting shapes together.

Downloads

Other Resources

How to spin (or rotate) a shape

Open original thread

Another cross post from Facebook. This was a question i had been looking for a answer to recently.

Zach Michels - If I had a Navigator, could I spin shapes I am making in Cortex from Cortex ramps? Most of the videos I see with Navigator are doing exciting things, but I don’t feel like I’ve seen examples of this. I understand that with the release of Shapechanger this will be possible, right? Any one who has a Navigator wanna make an example video?
Cheers all.

Lars Larsen - The missing ingredient for what you’re describing is an H/V mirroring (saw-to-triangle) circuit. If you want to rotate a 2D shape, you need to rotate the ramp waveforms, THEN perform H/V mirroring/saw-to-triangle conversion on both ramps, and then you would be ready to mix or combine them in some way to create a 2D shape key.

Navigator includes the facility for mirroring, but its mirrors are placed BEFORE rotation, in the signal path – this is great for quadrilateral/bilateral mirroring when feeding Shapechanger, but does little if you want to create a rotated shape without the Navigator+Shapechanger combo.

Lars Larsen - To make myself doubly clear, (1) The Navigator+Shapechanger combo gives full 2D shape generation/rotation (in the spinning the shape clockwise/ccw sense.) (2) If you want to do this with Navigator alone, you need a way to (a) mirror your HV ramps post-Navigator, (b) mix/combine them in some way, (c) generate a key of that mix, such as with Doorway or Cortex. FYI, Staircase is five mirror circuits in series! So a pair of them could mirror H/V and then keep going…

Lars Larsen - In fact, Navigator+2xStaircase makes for a pretty interesting pattern/geometry voice in its own right. These kind of relationships are what the XY series modules are all about!

Lars Larsen - When imagining patches, it may also be helpful to think of Navigator as positioning/rotating a camera, rather than the shape itself.

Zach Michels - Ok… more like rotating the reference frame than the object kind of?

Lars Larsen - Yes! Because everything derived from the ramps which have been rotated will have their own geometries rotated identically. Say you have a Navigator with HV outs multed to 2x Shapechangers. One creates an ellipse, another a squiggle. When the Navigator rotates the ramps, both shapes will rotate, as if a camera pointed at them is spinning.

Lars Larsen - For me, a video synthesizer “voice” consists of 2 components: one for spatial parameters (position and rotation) and one for geometry (width/height, curve). Think of it like the VCF-to-VCA relationship in a monosynth. Usually the VCF is before the VCA, but you can also do it the other way around create different and interesting results. Navigator+Shapechanger present to you a holistic approach to the spatial+goemetry processor concept, but there are other ways to patch up the essential pieces of ramp processing based shape generation.

Thread Replies

Jim posted #2 on Aug 9, 2018

Would the H/V mirroring now be possible with Arch?

Lars Larsen posted #3 in reply to #2 on Aug 9, 2018

Yes it would! But you’d need two mirror functions (for H and V separately, before combining them.)

Jim posted #4 on Aug 9, 2018

So my main reason for wanting Shapechanger is to spin a shape. What would be the signal path to use Arch and achieve this.

Something like this

H Ramps >Arch > Bridge Mixer > Navigator
V Ramps > Arch >

Lars Larsen posted #5 in reply to #4 on Aug 9, 2018

You’ve almost got it! Like that, but with Navigator between Ramps and arches. The patch above would give you double mirroring on the input to Navigator.

You can also use Staircase to do mirror function, but may have to tweak it a little to dial it in.

3 of the 4 functions in Arch are patched out utility block versions of some of the Shapechanger circuitry!

Jim posted #6 on Aug 9, 2018

I tried by using Staircase for the second H mirror and was able to spin things!!! Still need to tweak some more but will share some notes over the weekend. I may need to head out and grab a second Arch.

I’m using doorway to try and scale but looks like I’m missing the ability to skew the ramps from what I’ve learned from watching videos of how Shapechnager behaves.

Jim posted #7 on Aug 9, 2018

What I’m looking to do at its simplest is have a white diamond shape spinning 360” set against a black background.

Would this be possible without the scale and skew functions of Shapechanger?

Luis posted #8 on Aug 9, 2018

what is the analog function of the mirror? just wondering what it does to the signals… if its just rectifiers or something else?

Lars Larsen posted #9 in reply to #8 on Aug 9, 2018

It is an absolute rectifier (very fast, with video opamps and high speed schottky diodes) but in a frequency doubling configuration. So the input signal as 0-1V is scaled to +/-1V so that it will slice right in the center. The rectifier then slices positive/negative portions and inverts the negative portion to give 0-1V on output, but at double frequency.

Lars Larsen posted #10 in reply to #7 on Aug 9, 2018

Yes you can get a white diamond rotating that way! You will want to run H/V ramps into Navigator, then essentially you are doing a sawtooth to triangle (frequency doubler) conversion on the outputs. You can use Arch to do that or Staircase (at low frequency settings, you want 2X). Basically you are converting the sawtooth ramps into triangle ramps AFTER the rotation. Then you mix them (a crossfader works well for this, and gives you something similar to the skew control) and then you key them (using Doorway or Cortex) to get the flat shape results.

dni_br posted #11 on Aug 10, 2018

Hello,
so if navigator doesn t spin a shape, wath exactly does it do ?.
thx

Jim posted #13 on Aug 10, 2018

Navigator does spin the shape but from my understanding the mirrroring needs to take place after which is why I’m using Arch as a replacement for Shapechanger.

Lars Larsen posted #14 on Aug 10, 2018

Navigator rotates the XY dimensions of the “scene” that the shape is created within.

Jim posted #17 on Aug 25, 2018

Even more :slight_smile:

I’ve been waiting a long time to get this technique down so please bear with me sharing lots of experiments.

Patch notes to follow.

Jim posted #18 on Aug 25, 2018

Patch notes.

This is the patch for the videos above but if you were to remove Navigator you would still achieve the same look. Also im using one Staircase and one Arch. A cheaper route would be to use 2 x Arch. If you were to use 2 x Staircase that would up open up a world of variation but would be a bit more expensive.

The videos basically show the same patch but with different levels of mirroring switched on. Spinning shapes 1 shows the patch with all mirroring switched off. The only mirroring is whats taking place via arch and staircase to draw the shape. The rest of the videos show different combinations of the mirroring options on VC ramps and Navigator switched on.

Jim posted #19 on Aug 25, 2018

More variations. Similar kind of as patch as before.

Jim posted #21 on Jan 4, 2019

I didn’t get round the grabbing a second Arch but its on my wish list. I had filled my current case and only just started setting up a second case for new stuff so now can start planning to expand.

Timo Juntunen posted #22 on Jan 4, 2019

Would Arch bring a lot to a setup that already has Shapechanger in terms of bending and shaping things?

Jim posted #24 in reply to #22 on Jan 4, 2019

Yes for sure. Arch is my favourite module by far. Can get a world of shape variations of out when using ramps. Also processing control signals can get some amazing results.

Timo Juntunen posted #25 on Jan 4, 2019

Cool! I’m having a bit trouble understanding logic stuff in video synthesis. I just got the multi gate and love it but I guess arch is doing something entirely different to the signal.

Lars Larsen posted #27 in reply to #26 on Jan 4, 2019

I got Photoshop 3.0 at 8 years old and it’s been a continual source of inspiration! A lot of the work on Expedition series is from looking at the way computer graphics evolved from analog computing, and then figuring out ways to do the next level of analog by emulating a lot of the computer graphics workflows. For example, Shapechanger + Navigator perform a lot of the same math you’ll find in any 2D graphics engine, only they do it with analog computing circuitry. Marble Index (and Cortex Compositor) perform a lot of the same blending modes math you’ll find behind Photoshop or more robust digital compositing suites, only they likewise do it with analog circuitry. Most of the design challenge has been on how to take these functions and present them in a patchable hardware way, UI wise, and design analog circuits that do the math.

Bill Wiatroski posted #29 on Jan 4, 2019

Arch is my favorite too, You should see what you can do with four :slight_smile:

Bill Wiatroski posted #30 in reply to #23 on Jan 4, 2019

Speaking from experience, the best way to augment MP is with a solid analog synthesis setup behind it. It is a ground breaking module, but to truly exploit it’s power feed it the best material. It will do really cool things with live video input and still frames, but IMO where it really shines is as an integral part of diverse system. That said, you can do some awfully cool stuff with just a Vidot and an MP :slight_smile:

Bill Wiatroski posted #31 in reply to #30 on Jan 4, 2019

And now I’m completely off topic :slight_smile:

Josh Reineke posted #33 in reply to #18 on Dec 12, 2019

Even though I have a Shapechanger, these patches are very educational. Thanks!

nerdware posted #34 in reply to #33 on Dec 12, 2019

Yes, thanks! Every little trick helps. I’m at the stage now where I’m looking for new layers to add to a patch, and I’ll look to any modules that are as-yet-unused-in-this-patch to do this.

Ollie @martindevices posted #35 on Aug 23, 2022

Big bump!

I’m playing about trying to rotate some shapes with mostly 4HP Cadet and other DIY modules, does anyone have a nice block diagram for simple shape rotation?

rempesm posted #36 in reply to #35 on Aug 23, 2022

I’ll draw up a diagram in a minute.

nerdware posted #37 in reply to #36 on Aug 23, 2022

I don’t know who did these or recall where I got them (probably here), but I have some useful images. I’ll see if I can upload them.

[EDIT]

Sorry, every upload attempt fails.

nerdware posted #38 in reply to #36 on Aug 23, 2022

Ahh, yes. From another forum, years earlier, a diagram of basic Rutt Etra. Now I need to find the source for the other image, a diagram illustrating the rotations using phase quadrature.

Lars Larsen posted #39 on Aug 23, 2022

Note that there are some exceptions – for example, the “CROSS” switch on Navigator inverts one of the Sin/Cos outputs, so that one output rotates the opposite direction from the other (creating a kind of perspective morph rather than a rotation.) In other words, there are lots of fun ways to patch it up, which are similar to but not the exact same as the textbook rotation formula.

Robin Burke posted #42 in reply to #40 on Aug 29, 2022

Cheers @sprthhfk for posting the 2nd picture in particular. I was aware of the first & I found that it helped or worked but was a lot of modules just to perform a rotation, especesially how the Prismatic Ray was used.
The 2nd image makes so much sense but if someone doesn’t have an Arch, the top right corner (2x recitifier) can be done with a Syntonie VU-002 or Staircase just dialled a fraction. But how about the top left of Arch? It’s the min output function under the two inputs.

Jim posted #43 in reply to #42 on Aug 29, 2022

The prismatic ray is not necessary for the basic action of spinning a shape. The patch notes i posted were showing how to recreate the effect in the videos i had posted along with them.
You can remove the final part of the patch after arch and bridge for a basic spinning shape patch. The Prismatic Ray was just used for the spinning lines that were overlaid over the main spinning shape part of the patch.

Robin Burke posted #44 in reply to #43 on Aug 30, 2022

Cheers for clarifying that @destroythings :+1:t3:
I was just gotten a bunch of Expedition modules at the time I tried it so I most likely messed up a part of the patch before it hit the Prismatic Ray.
I’m glad to see you’re still on here & that this thread you created is still relevant & of interest to people on here :grinning:
I’m still minus a Shapechanger so it’s most definitely relevant to me :sweat_smile:

Discuss on the Expedition series overview · Search forum for Shapechanger · Search forum