Interpreting a rotary encoder, the Supercollider way

Hello all.

I want to get the position of my ACE-128 encoder. I’ve got it working with C++, but am working to do the same in Supercollider (this is because, from what I’ve read, it is impossible to run a C++ program decoding the encoder and then pipe this information to a Supercollider instance running in parallel — if there’s a clean way, then I’m all ears!).

The rotary encoder outputs a number between 0 and 255. These values serve as indices which are used to look up the encoder’s true position stored in an array. With the code below, I’m just trying to test getting the digital inputs, converting these to a decimal value, and then looking up the encoder’s position in the map array. The “~rotaryMonitor” is inspired by this: https://forum.bela.io/d/669-triggering-synths-with-digitalin-in-supercollider and I’m intending to somehow take a similar approach… if of course I can actually figure out how to map the encoder’s output to its positions.

It seems that the DigitalIn() function doesn’t immediately output an integer value, which in turn means a “DigitalIn” object is being used when I try to calculate the decimal value, and in turn a non-integer object is used for the array index. In the end, an error is thrown saying that the Index is not an Integer.

I understand that Supercollider on Bela is instantiating a hardcoded synth on a server, and then I need to communicate through OSC from the client to update parameters. The goal is to somehow get my 128-position encoder’s changes calculated and piped over to the server at control rate, but I am having trouble thinking the “Supercollider way”. Does anyone have guidance on this?

// variables for reading Encoder
~gEncoderPin1 = 2;
~gEncoderPin2 = 3;
~gEncoderPin3 = 4;
~gEncoderPin4 = 5;
~gEncoderPin5 = 6;
~gEncoderPin6 = 7;
~gEncoderPin7 = 8;
~gEncoderPin8 = 9;

~encoderMap_12345678 = Array[
  0xFF,0x38,0x28,0x37,0x18,0xFF,0x27,0x34,0x08,0x39,0xFF,0xFF,0x17,0xFF,0x24,0x0D,
  0x78,0xFF,0x29,0x36,0xFF,0xFF,0xFF,0x35,0x07,0xFF,0xFF,0xFF,0x14,0x13,0x7D,0x12,
  0x68,0x69,0xFF,0xFF,0x19,0x6A,0x26,0xFF,0xFF,0x3A,0xFF,0xFF,0xFF,0xFF,0x25,0x0E,
  0x77,0x76,0xFF,0xFF,0xFF,0x6B,0xFF,0xFF,0x04,0xFF,0x03,0xFF,0x6D,0x6C,0x02,0x01,
  0x58,0xFF,0x59,0xFF,0xFF,0xFF,0xFF,0x33,0x09,0x0A,0x5A,0xFF,0x16,0x0B,0xFF,0x0C,
  0xFF,0xFF,0x2A,0x2B,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0x15,0xFF,0x7E,0x7F,
  0x67,0xFF,0x66,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0x5B,0xFF,0xFF,0xFF,0xFF,0xFF,
  0x74,0x75,0xFF,0xFF,0x73,0xFF,0xFF,0xFF,0x5D,0x5E,0x5C,0xFF,0x72,0x5F,0x71,0x00,
  0x48,0x47,0xFF,0x44,0x49,0xFF,0xFF,0x1D,0xFF,0x46,0xFF,0x45,0xFF,0xFF,0x23,0x22,
  0x79,0xFF,0x7A,0xFF,0x4A,0xFF,0xFF,0x1E,0x06,0xFF,0x7B,0xFF,0xFF,0xFF,0x7C,0x11,
  0xFF,0xFF,0xFF,0x43,0x1A,0xFF,0x1B,0x1C,0xFF,0x3B,0xFF,0xFF,0xFF,0xFF,0xFF,0x0F,
  0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0x05,0xFF,0xFF,0xFF,0x6E,0xFF,0x6F,0x10,
  0x57,0x54,0xFF,0x2D,0x56,0x55,0xFF,0x32,0xFF,0xFF,0xFF,0x2E,0xFF,0xFF,0xFF,0x21,
  0xFF,0x53,0xFF,0x2C,0x4B,0xFF,0xFF,0x1F,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0x20,
  0x64,0x3D,0x65,0x42,0xFF,0x3E,0xFF,0x31,0x63,0x3C,0xFF,0x2F,0xFF,0xFF,0xFF,0x30,
  0x4D,0x52,0x4E,0x41,0x4C,0x3F,0xFF,0x40,0x62,0x51,0x4F,0x50,0x61,0x60,0x70,0xFF];

// 8-Bit to decimal function for rotary encoder
~binaryToDecimal = {
	arg a, b, c, d, e, f, g, h;
	(a * 128) + (b * 64) + (c * 32) + (d * 16) + (e *  + (f * 4) + (g * 2) + h;
};

// Just mapping the rotary encoder's 8 pins to the counting function
~rotaryToDecimal = {
	~binaryToDecimal.value(
		DigitalIn.kr(~gEncoderPin8),
		DigitalIn.kr(~gEncoderPin7),
		DigitalIn.kr(~gEncoderPin6),
		DigitalIn.kr(~gEncoderPin5),
		DigitalIn.kr(~gEncoderPin4),
		DigitalIn.kr(~gEncoderPin3),
		DigitalIn.kr(~gEncoderPin2),
		DigitalIn.kr(~gEncoderPin1)
	);
};

s = Server.default;

// Set up options for the Bela
s.options.numAnalogInChannels = 2;
s.options.numAnalogOutChannels = 2;
s.options.numDigitalChannels = 16;
s.options.maxLogins = 4;
s.options.bindAddress = "0.0.0.0"; // allow anyone on the network connect to this server

s.options.blockSize = 16;
s.options.numInputBusChannels = 2;
s.options.numOutputBusChannels = 2;

s.waitForBoot {
	~rotaryMonitor = {
		var d = ~rotaryToDecimal.value();
		var pos = ~encoderMap_12345678.at(d); // Throws exception... "Index not an Integer"
		pos.postln;
	}.play;
	
	// Simple synth
	{RLPF.ar(Dust.ar([1, 100]), LFNoise1.ar([1, 0.2]).range(100, 3000), 0.001)}.play;
};

ServerQuit.add({ 0.exit }); // quit if the button is pressed