revmodel.cpp

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// Reverb model implementation
//
// Written by Jezar at Dreampoint, June 2000
// http://www.dreampoint.co.uk
// This code is public domain

#include "stdafx.h"
#include "revmodel.h"
#include "TfreeverbSettings.h"

const float fixedgain           = 0.015f;
const float muted               = 0;
const float freezemode          = 0.5f;
const float scaledry            = 2;
const float scaledamp           = 0.4f;
const float scaleroom           = 0.28f;
const float offsetroom          = 0.7f;

revmodel::revmodel()
{
	// Tie the components to their buffers
	combL[0].setbuffer(bufcombL1,combtuningL1);
	combR[0].setbuffer(bufcombR1,combtuningR1);
	combL[1].setbuffer(bufcombL2,combtuningL2);
	combR[1].setbuffer(bufcombR2,combtuningR2);
	combL[2].setbuffer(bufcombL3,combtuningL3);
	combR[2].setbuffer(bufcombR3,combtuningR3);
	combL[3].setbuffer(bufcombL4,combtuningL4);
	combR[3].setbuffer(bufcombR4,combtuningR4);
	combL[4].setbuffer(bufcombL5,combtuningL5);
	combR[4].setbuffer(bufcombR5,combtuningR5);
	combL[5].setbuffer(bufcombL6,combtuningL6);
	combR[5].setbuffer(bufcombR6,combtuningR6);
	combL[6].setbuffer(bufcombL7,combtuningL7);
	combR[6].setbuffer(bufcombR7,combtuningR7);
	combL[7].setbuffer(bufcombL8,combtuningL8);
	combR[7].setbuffer(bufcombR8,combtuningR8);
	allpassL[0].setbuffer(bufallpassL1,allpasstuningL1);
	allpassR[0].setbuffer(bufallpassR1,allpasstuningR1);
	allpassL[1].setbuffer(bufallpassL2,allpasstuningL2);
	allpassR[1].setbuffer(bufallpassR2,allpasstuningR2);
	allpassL[2].setbuffer(bufallpassL3,allpasstuningL3);
	allpassR[2].setbuffer(bufallpassR3,allpasstuningR3);
	allpassL[3].setbuffer(bufallpassL4,allpasstuningL4);
	allpassR[3].setbuffer(bufallpassR4,allpasstuningR4);

	// Set default values
	allpassL[0].setfeedback(0.5f);
	allpassR[0].setfeedback(0.5f);
	allpassL[1].setfeedback(0.5f);
	allpassR[1].setfeedback(0.5f);
	allpassL[2].setfeedback(0.5f);
	allpassR[2].setfeedback(0.5f);
	allpassL[3].setfeedback(0.5f);
	allpassR[3].setfeedback(0.5f);

	// Buffer will be full of rubbish - so we MUST mute them
	//mute();
}

void revmodel::mute()
{
	int i;

	if (getmode() >= freezemode)
		return;

	for (i=0;i<numcombs;i++)
	{
		combL[i].mute();
		combR[i].mute();
	}
	for (i=0;i<numallpasses;i++)
	{
		allpassL[i].mute();
		allpassR[i].mute();
	}
}

void revmodel::processreplace(float *l, float *r,int numsamples, int skip)
{

	while(numsamples-- > 0)
	{
		float input = (*l + *r) * gain;
                float outL=0,outR=0;

		// Accumulate comb filters in parallel
		int i;
		for(i=0; i<numcombs; i++)
		{
			outL += combL[i].process(input);
			outR += combR[i].process(input);
		}

		// Feed through allpasses in series
		for(i=0; i<numallpasses; i++)
		{
			outL = allpassL[i].process(outL);
			outR = allpassR[i].process(outR);
		}

		// Calculate output REPLACING anything already there
		*l = outL*wet1 + outR*wet2 + *l*dry;
		*r = outR*wet1 + outL*wet2 + *r*dry;

		// Increment sample pointers, allowing for interleave (if any)
		l += skip;
		r += skip;
	}
}

void revmodel::update()
{
// Recalculate internal values after parameter change

	int i;

	wet1 = wet*(width/2 + 0.5f);
	wet2 = wet*((1-width)/2);

	if (mode >= freezemode)
	{
		roomsize1 = 1;
		damp1 = 0;
		gain = muted;
	}
	else
	{
		roomsize1 = roomsize;
		damp1 = damp;
		gain = fixedgain;
	}

	for(i=0; i<numcombs; i++)
	{
		combL[i].setfeedback(roomsize1);
		combR[i].setfeedback(roomsize1);
	}

	for(i=0; i<numcombs; i++)
	{
		combL[i].setdamp(damp1);
		combR[i].setdamp(damp1);
	}
}

// The following get/set functions are not inlined, because
// speed is never an issue when calling them, and also
// because as you develop the reverb model, you may
// wish to take dynamic action when they are called.

void revmodel::setroomsize(float value)
{
	roomsize = (value*scaleroom) + offsetroom;
	update();
}

float revmodel::getroomsize()
{
	return (roomsize-offsetroom)/scaleroom;
}

void revmodel::setdamp(float value)
{
	damp = value*scaledamp;
	update();
}

float revmodel::getdamp()
{
	return damp/scaledamp;
}

void revmodel::setwet(float value)
{
	wet = value*TfreeverbSettings::scalewet;
	update();
}

float revmodel::getwet()
{
	return wet/TfreeverbSettings::scalewet;
}

void revmodel::setdry(float value)
{
	dry = value*scaledry;
}

float revmodel::getdry()
{
	return dry/scaledry;
}

void revmodel::setwidth(float value)
{
	width = value;
	update();
}

float revmodel::getwidth()
{
	return width;
}

void revmodel::setmode(float value)
{
	mode = value;
	update();
}

float revmodel::getmode()
{
	if (mode >= freezemode)
		return 1;
	else
		return 0;
}

//ends