tal-reverb-2-juce/src/Engine/ParamChangeUtil.h

   1 /*
   2         ==============================================================================
   3         This file is part of Tal-Reverb by Patrick Kunz.
   4
   5         Copyright(c) 2005-2009 Patrick Kunz, TAL
   6         Togu Audio Line, Inc.
   7         http://kunz.corrupt.ch
   8
   9         This file may be licensed under the terms of of the
  10         GNU General Public License Version 2 (the ``GPL'').
  11
  12         Software distributed under the License is distributed
  13         on an ``AS IS'' basis, WITHOUT WARRANTY OF ANY KIND, either
  14         express or implied. See the GPL for the specific language
  15         governing rights and limitations.
  16
  17         You should have received a copy of the GPL along with this
  18         program. If not, go to http://www.gnu.org/licenses/gpl.html
  19         or write to the Free Software Foundation, Inc.,
  20         51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  21         ==============================================================================
  22  */
  23
  24
  25 #if !defined(__ParamChangeUtil_h)
  26 #define __ParamChangeUtil_h
  27
  28 #include "Math.h"
  29
  30 // Low pass filter for gentle parameter changes
  31 class ParamChangeUtil
  32 {
  33 private:
  34         float currentValue;
  35         float paramWeight;
  36         float paramWeigthInverse;
  37
  38 public:
  39         // param weight should be bigger than 1
  40         ParamChangeUtil(float sampleRate, float paramWeight)
  41         {
  42                 currentValue = 0;
  43                 this->paramWeight = paramWeight * sampleRate / 44100.0f;
  44                 paramWeigthInverse = 1.0f / (this->paramWeight + 1.0f);
  45         }
  46
  47         inline float tick(float input)
  48         {
  49                 currentValue = (paramWeight * currentValue + input) * paramWeigthInverse;
  50                 return currentValue;
  51         }
  52 };
  53 #endif