Rack/plugins/community/repos/bsp/src/Sway.cpp

/*
Copyright (c) 2018 bsp

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
*/

#include <math.h>

#include "bsp.hpp"

namespace rack_plugin_bsp {

struct Sway : Module {
	enum ParamIds {
		MIN_T_PARAM,
		MAX_T_PARAM,
		MIN_A_PARAM,
		MAX_A_PARAM,
      SCALE_A_PARAM,
      OFFSET_A_PARAM,
		NUM_PARAMS
	};
	enum InputIds {
		NUM_INPUTS
	};
	enum OutputIds {
		CTL_OUTPUT,
		NUM_OUTPUTS
	};

   static const int32_t SCALE_T_SEC = 60;
   static const int32_t SCALE_MAX = 5;

	float sampleRate;

   float cur_rand_val_step;
   float cur_rand_val;
   int   cur_rand_val_countdown;

   float last_min_t;
   float last_max_t;

#if 0
	void onRandomize() override {
      cur_rand_val_countdown = -1;
   }
#endif

   static float randf(float _max) {
      return ((rand()*(0.999999999999f / float(RAND_MAX))) * _max);
   }

   void handleSampleRateChanged(void) {
      sampleRate = engineGetSampleRate();
   }

	Sway() : Module(NUM_PARAMS, NUM_INPUTS, NUM_OUTPUTS) {
      handleSampleRateChanged();
      cur_rand_val_countdown = -1;
   }

	void step() override;

	void onReset() override {
      handleSampleRateChanged();
	}

   void onSampleRateChange() override {
      Module::onSampleRateChange();

      handleSampleRateChanged();
   }
};


void Sway::step() {

   if(params[MIN_T_PARAM].value != last_min_t)
   {
      last_min_t = params[MIN_T_PARAM].value;
      cur_rand_val_countdown = -1;
   }
   else if(params[MAX_T_PARAM].value != last_max_t)
   {
      last_max_t = params[MAX_T_PARAM].value;
      cur_rand_val_countdown = -1;
   }

   if(cur_rand_val_countdown < 0)
   {
      // First sample after reset / init
      float minA = params[MIN_A_PARAM].value;
      float maxA = params[MAX_A_PARAM].value;

      if(minA > maxA)
      {
         float t = minA;
         minA = maxA;
         maxA = t;
      }

      cur_rand_val = randf(maxA - minA) + minA;
   }

   if(--cur_rand_val_countdown <= 0)
   {
      // Next target val
      float minT = params[MIN_T_PARAM].value;
      float maxT = params[MAX_T_PARAM].value;
      float minA = params[MIN_A_PARAM].value;
      float maxA = params[MAX_A_PARAM].value;

      // Sort min / max
      if(minT > maxT)
      {
         float t = minT;
         minT = maxT;
         maxT = t;
      }

      if(minA > maxA)
      {
         float t = minA;
         minA = maxA;
         maxA = t;
      }

      // Bias towards slow modulation
      minT = minT * minT;
      minT = minT * minT;

      maxT = maxT * maxT;
      maxT = maxT * maxT;

      cur_rand_val_countdown = int((randf(maxT - minT) + minT) * (sampleRate * float(SCALE_T_SEC)));
      if(cur_rand_val_countdown < 1)
         cur_rand_val_countdown = 1;

      float nextVal = randf(maxA - minA) + minA;
      cur_rand_val_step = (nextVal - cur_rand_val) / cur_rand_val_countdown;
   }

   cur_rand_val += cur_rand_val_step;

	// Set output
	      float scaleA = params[SCALE_A_PARAM].value;
	const float offA   = params[OFFSET_A_PARAM].value;

   // Bias towards subtle modulation
   scaleA = scaleA * scaleA;
   scaleA = scaleA * scaleA;
   scaleA *= float(SCALE_MAX);

	outputs[CTL_OUTPUT].value = cur_rand_val * scaleA + offA;
}


struct SwayWidget : ModuleWidget {
	SwayWidget(Sway *module);

#if 0
   void randomize() override {
      module->onRandomize();
   }
#endif
};

SwayWidget::SwayWidget(Sway *module) : ModuleWidget(module) {
	setPanel(SVG::load(assetPlugin(plugin, "res/Sway.svg")));

	addChild(Widget::create<ScrewSilver>(Vec(15, 0)));
	addChild(Widget::create<ScrewSilver>(Vec(15, 365)));

	// addParam(ParamWidget::create<CKSS>(Vec(15, 50), module, Obxd_VCF::FOURPOLE_PARAM, 0.0f, 1.0f, 0.0f));

#define HL 55
#define HS 40
   float cx = 9.0f;
   float cy = 50.0f;
	addParam(ParamWidget::create<RoundBlackKnob>(Vec(cx, cy), module, Sway::MIN_T_PARAM, 0.0f, 1.0f, 0.2f));
   cy += HS;
	addParam(ParamWidget::create<RoundBlackKnob>(Vec(cx, cy), module, Sway::MAX_T_PARAM, 0.0f, 1.0f, 0.3f));
   cy += HL;
	addParam(ParamWidget::create<RoundBlackKnob>(Vec(cx, cy), module, Sway::MIN_A_PARAM, -1.0f, 1.0f, -1.0f));
   cy += HS;
	addParam(ParamWidget::create<RoundBlackKnob>(Vec(cx, cy), module, Sway::MAX_A_PARAM, -1.0f, 1.0f, 1.0f));
   cy += HL;
	addParam(ParamWidget::create<RoundBlackKnob>(Vec(cx, cy), module, Sway::SCALE_A_PARAM, 0.0f, 1.0f, 0.1f));
   cy += HS;
	addParam(ParamWidget::create<RoundBlackKnob>(Vec(cx, cy), module, Sway::OFFSET_A_PARAM,-5.0f, 5.0f, 0.0f));

	addOutput(Port::create<PJ301MPort>(Vec(11, 325), Port::OUTPUT, module, Sway::CTL_OUTPUT));
}

} // namespace rack_plugin_bsp

using namespace rack_plugin_bsp;

RACK_PLUGIN_MODEL_INIT(bsp, Sway) {
   Model *modelSway = Model::create<Sway, SwayWidget>("bsp", "Sway", "Sway", NOISE_TAG, OSCILLATOR_TAG, LFO_TAG);
   return modelSway;
}