a simple drum synth

engine-study.lua

engine.name = "BloopDrum"

engine.kick()
engine.snare()
engine.hihat()

Engine_BloopDrum.sc

Engine_BloopDrum : CroneEngine {

	var pg; // pg is a "parallel group", see the alloc ~20 lines down

	*new { arg context, doneCallback;
		^super.new(context, doneCallback);
	}

	alloc {
		pg = ParGroup.tail(context.xg);

		// add SynthDefs
		SynthDef("hihat", {arg out = 0, amp = 0.5, att = 0.01, rel = 0.2, ffreq = 6000, pan = 0;
			var env, snd;
			env = Env.perc(att, rel, amp).kr(doneAction: 2);
			snd = WhiteNoise.ar;
			snd = HPF.ar(in: snd, freq: ffreq, mul: env);
			Out.ar(out, Pan2.ar(snd, pan));
		}).add;
    
		SynthDef("snare", {arg out = 0, amp = 0.1, sinfreq = 180, att = 0.01, rel = 0.2, ffreq = 2000, pan = 0;
			var env, snd1, snd2, sum;
			env = Env.perc(att, rel, amp).kr(doneAction: 2);
			snd1 = HPF.ar(
				in: WhiteNoise.ar,
				freq: ffreq,
				mul: env
			);
			snd2 = SinOsc.ar(freq: sinfreq, mul: env);
			sum = snd1 + snd2;
			Out.ar(out, Pan2.ar(sum, pan));
		}).add;
		
		SynthDef("kick", {arg out = 0, amp = 0.3, sinfreq = 60, glissf = 0.9, att = 0.01, rel = 0.45, pan = 0;
			var env, snd, ramp;
			env = Env.perc(att, rel, amp).kr(doneAction: 2);
			ramp = XLine.kr(
				start: sinfreq,
				end: sinfreq * glissf,
				dur: rel
			);
			snd = SinOsc.ar(freq: ramp, mul: env);
			snd = Pan2.ar(snd, pan);
			Out.ar(out, snd);
		}).add;
		
		context.server.sync;

		this.addCommand("hihat", "", { arg msg;
			Synth("hihat", [\out, context.out_b], target:pg);
		});

		this.addCommand("snare", "", { arg msg;
			Synth("snare", [\out, context.out_b], target:pg);
		});
		
		this.addCommand("kick", "", { arg msg;
			Synth("kick", [\out, context.out_b], target:pg);
		});
		
	}

}