Is Y normalled to 1?
Yes, that would allow you to do IQ color picking and offsets. Color rotation (like continuous hue cycling) will require a rotator module.
Is Y normalled to 1?
Y input (of the YIQ to RGB side) is normalled to Y output (of the RGB to YIQ side). The RGB inputs are normalled to 0V (Black.)
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I can see that I need to take a closer look at how YIQ works.
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Edit: Rewrote this reply after the first attempt.
If you are patching from arbitrary sources (oscillators, ramps, keys) directly into the YIQ inputs, it’s possible to generate illegal YIQ colors. Illegal colors can be a good thing! But to generate a legal YIQ source, where IQ are constrained by Y’s amplitude, you need a saturation processor (dual VCA) so that you can multiply Y with IQ. You also need a quadrature source for IQ where the outputs are 90 degrees out of phase, like a quadrature oscillator or polar-to-cartesian function.
Without a YIQ generator, you should go in thru the RGB inputs with your image – and then go into IQ- inputs, with your modulation sources (like XY from a joystick.) The RGB outs will then be the RGB source image, but with IQ distorted by the joystick’s offsets.
Swatch is a YIQ converter, and the Polar-to-Cartesian module that is following it up can be used as a YIQ generator. The rotation/affine module that is also coming can be used as an IQ modulator. Together they can be patched as a comprehensive YIQ manipulator/generator/rotator tool suite. Swatch on it’s own has lots of tricks and utility, but is not the full picture.
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I think I am getting it now.
One wants to think of YIQ as separating the luma and chroma values. Wherein the final RGB is always some multiplication of Y times IQ (0y equals black; 1y equals full saturation or white).
But, in actuality, IQ is always (supposed to be) relational to Y (hence the requirement for VCA treatment before input into IQ). And the math behind the YIQ to RGB conversion is addition/subtraction, not multiplication. So you can have a Y value of 0 and still end up with an image, even though logically that doesn’t make sense (under the more conventional HSV way of thinking about color).
…Okay, just noticed that you rewrote your description and made it clearer (and maybe better than what I just said). But I am pretty confident that I get it now.
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If you’re wondering why we didn’t combine all this into one big module – we did! That’s what Chromagnon is. 
Breaking it up into modules, Swatch has a very special place – it allows Chroma to exist in the same signal path as general use vector processors for shape generation or scan processing. So we can release “generic rotator module” and you won’t need separate variants for chroma rotator, shape rotator, scan rotator, etc.
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I will admit that, for my purposes, the original Color Wheel module concept could’ve perhaps been more useful. Or even something stripped back from that, with only RGB ins/outs and then the control over HSV.
But I totally appreciate why breaking it out with more modularity is practically more realistic and functionally more exciting.
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Color Wheel is still going to be entirely present, as well as the functions of Mapper, Navigator, Polar Fringe, and Shapechanger, in the functional set of these three modules alone – so you may feel different when you see it all together. Nothing prevents us from doing a Color Wheel module – but modular roadmap wise, doing the modular functions first means we have a Color Wheel function, and also cover a lot of territory beyond it.
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Can we get some of the Swatch demo videos back on-line? The “twitch” content was removed I think and I didn’t get a chance to watch all the content.
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The last LZX J. Woods Youtube vid made mention of a Swatch vid on the way I think.
Twitch streams are indeed lengthy and fun but the archival nature of the Youtube content is nice as a ref manal of sorts.
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Yes, Johnny’s working on a video. I also posted some patching tips here.
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Thanks for the Swatch vid details! Gonna go back and watch some of the twitch ones and looking forward to Johnny’s video!!!
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