juce_MPEZoneLayout.h

/*
  ==============================================================================
 
   This file is part of the JUCE library.
   Copyright (c) 2022 - Raw Material Software Limited
 
   JUCE is an open source library subject to commercial or open-source
   licensing.
 
   The code included in this file is provided under the terms of the ISC license
   http://www.isc.org/downloads/software-support-policy/isc-license. Permission
   To use, copy, modify, and/or distribute this software for any purpose with or
   without fee is hereby granted provided that the above copyright notice and
   this permission notice appear in all copies.
 
   JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
   EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
   DISCLAIMED.
 
  ==============================================================================
*/
 
namespace juce
{
 
//==============================================================================
struct MPEZone
{
    enum class Type { lower, upper };
 
    MPEZone() = default;
 
    MPEZone (Type type, int memberChannels = 0, int perNotePitchbend = 48, int masterPitchbend = 2)
        : zoneType (type),
          numMemberChannels (memberChannels),
          perNotePitchbendRange (perNotePitchbend),
          masterPitchbendRange (masterPitchbend)
    {}
 
    bool isLowerZone() const noexcept             { return zoneType == Type::lower; }
    bool isUpperZone() const noexcept             { return zoneType == Type::upper; }
 
    bool isActive() const noexcept                { return numMemberChannels > 0; }
 
    int getMasterChannel() const noexcept         { return isLowerZone() ? lowerZoneMasterChannel : upperZoneMasterChannel; }
    int getFirstMemberChannel() const noexcept    { return isLowerZone() ? lowerZoneMasterChannel + 1 : upperZoneMasterChannel - 1; }
    int getLastMemberChannel() const noexcept     { return isLowerZone() ? (lowerZoneMasterChannel + numMemberChannels)
                                                                         : (upperZoneMasterChannel - numMemberChannels); }
 
    bool isUsingChannelAsMemberChannel (int channel) const noexcept
    {
        return isLowerZone() ? (lowerZoneMasterChannel < channel && channel <= getLastMemberChannel())
                             : (channel < upperZoneMasterChannel && getLastMemberChannel() <= channel);
    }
 
    bool isUsing (int channel) const noexcept
    {
        return isUsingChannelAsMemberChannel (channel) || channel == getMasterChannel();
    }
 
    static auto tie (const MPEZone& z)
    {
        return std::tie (z.zoneType,
                         z.numMemberChannels,
                         z.perNotePitchbendRange,
                         z.masterPitchbendRange);
    }
 
    bool operator== (const MPEZone& other) const
    {
        return tie (*this) == tie (other);
    }
 
    bool operator!= (const MPEZone& other) const
    {
        return tie (*this) != tie (other);
    }
 
    //==============================================================================
    static constexpr int lowerZoneMasterChannel = 1,
                         upperZoneMasterChannel = 16;
 
    Type zoneType = Type::lower;
 
    int numMemberChannels     = 0;
    int perNotePitchbendRange = 48;
    int masterPitchbendRange  = 2;
};
 
//==============================================================================
class JUCE_API  MPEZoneLayout
{
public:
    //==============================================================================
    MPEZoneLayout() = default;
 
    MPEZoneLayout (MPEZone lower, MPEZone upper);
 
    MPEZoneLayout (MPEZone singleZone);
 
    MPEZoneLayout (const MPEZoneLayout& other);
    MPEZoneLayout& operator= (const MPEZoneLayout& other);
 
    bool operator== (const MPEZoneLayout& other) const { return lowerZone == other.lowerZone && upperZone == other.upperZone; }
    bool operator!= (const MPEZoneLayout& other) const { return ! operator== (other); }
 
    //==============================================================================
    MPEZone getLowerZone() const noexcept    { return lowerZone; }
 
    MPEZone getUpperZone() const noexcept    { return upperZone; }
 
    void setLowerZone (int numMemberChannels = 0,
                       int perNotePitchbendRange = 48,
                       int masterPitchbendRange = 2) noexcept;
 
    void setUpperZone (int numMemberChannels = 0,
                       int perNotePitchbendRange = 48,
                       int masterPitchbendRange = 2) noexcept;
 
    void clearAllZones();
 
    bool isActive() const  { return lowerZone.isActive() || upperZone.isActive(); }
 
    //==============================================================================
    void processNextMidiEvent (const MidiMessage& message);
 
    void processNextMidiBuffer (const MidiBuffer& buffer);
 
    //==============================================================================
    class Listener
    {
    public:
        virtual ~Listener() = default;
 
        virtual void zoneLayoutChanged (const MPEZoneLayout& layout) = 0;
    };
 
    //==============================================================================
    void addListener (Listener* const listenerToAdd) noexcept;
 
    void removeListener (Listener* const listenerToRemove) noexcept;
 
   #ifndef DOXYGEN
    using Zone = MPEZone;
   #endif
 
private:
    //==============================================================================
    MPEZone lowerZone { MPEZone::Type::lower, 0 };
    MPEZone upperZone { MPEZone::Type::upper, 0 };
 
    MidiRPNDetector rpnDetector;
    ListenerList<Listener> listeners;
 
    //==============================================================================
    void setZone (bool, int, int, int) noexcept;
 
    void processRpnMessage (MidiRPNMessage);
    void processZoneLayoutRpnMessage (MidiRPNMessage);
    void processPitchbendRangeRpnMessage (MidiRPNMessage);
 
    void updateMasterPitchbend (MPEZone&, int);
    void updatePerNotePitchbendRange (MPEZone&, int);
 
    void sendLayoutChangeMessage();
    void checkAndLimitZoneParameters (int, int, int&) noexcept;
};
 
} // namespace juce