Merge pull request #246 from jpcima/voice-lifecycle

Voice lifecycle
2020-06-13 23:40:57 +02:00 · 2020-06-13 23:40:57 +02:00 · 35837c501f
commit 35837c501f
parent 9b72dce802 0bbb1e930f
12 changed files with 231 additions and 53 deletions
--- a/benchmarks/BM_ADSR.cpp
+++ b/benchmarks/BM_ADSR.cpp
@ -35,7 +35,7 @@ public:
    }

    sfz::MidiState midiState;
-    sfz::Region region{midiState};
+    sfz::Region region{0, midiState};
    sfz::ADSREnvelope<float> envelope;
    std::vector<float> output;
 };
--- a/src/sfizz/NumericId.h
+++ b/src/sfizz/NumericId.h
@ -0,0 +1,41 @@
+// SPDX-License-Identifier: BSD-2-Clause
+
+// This code is part of the sfizz library and is licensed under a BSD 2-clause
+// license. You should have receive a LICENSE.md file along with the code.
+// If not, contact the sfizz maintainers at https://github.com/sfztools/sfizz
+
+#pragma once
+
+/**
+ * @brief Numeric identifier
+ *
+ * It is a generic numeric identifier. The template wrapper serves to enforce a
+ * stronger compile-time check, such that one kind of identifier can't be
+ * mistaken for another kind, or for an unrelated integer such as an index.
+ */
+template <class T>
+struct NumericId {
+    constexpr NumericId() = default;
+
+    explicit constexpr NumericId(int number)
+        : number(number)
+    {
+    }
+
+    constexpr bool valid() const noexcept
+    {
+        return number != -1;
+    }
+
+    constexpr bool operator==(NumericId other) const noexcept
+    {
+        return number == other.number;
+    }
+
+    constexpr bool operator!=(NumericId other) const noexcept
+    {
+        return number != other.number;
+    }
+
+    const int number = -1;
+};
--- a/src/sfizz/Region.h
+++ b/src/sfizz/Region.h
@ -16,6 +16,7 @@
 #include "AudioBuffer.h"
 #include "MidiState.h"
 #include "FileId.h"
+#include "NumericId.h"
 #include "absl/types/optional.h"
 #include <bitset>
 #include <string>
@ -35,8 +36,8 @@ namespace sfz {
 *
 */
 struct Region {
-    Region(const MidiState& midiState, absl::string_view defaultPath = "")
-    : midiState(midiState), defaultPath(std::move(defaultPath))
+    Region(int regionNumber, const MidiState& midiState, absl::string_view defaultPath = "")
+    : id{regionNumber}, midiState(midiState), defaultPath(std::move(defaultPath))
    {
        ccSwitched.set();

@ -46,6 +47,14 @@ struct Region {
    Region(const Region&) = default;
    ~Region() = default;

+    /**
+     * @brief Get the number which identifies this region
+     */
+    NumericId<Region> getId() const noexcept
+    {
+        return id;
+    }
+
    /**
     * @brief Triggers on release?
     *
@ -238,6 +247,8 @@ struct Region {
     */
    float getGainToEffectBus(unsigned number) const noexcept;

+    const NumericId<Region> id;
+
    // Sound source: sample playback
    FileId sampleId {}; // Sample
    int sampleQuality { Default::sampleQuality };
--- a/src/sfizz/Synth.cpp
+++ b/src/sfizz/Synth.cpp
@ -44,6 +44,13 @@ sfz::Synth::~Synth()
    resources.filePool.emptyFileLoadingQueues();
 }

+void sfz::Synth::onVoiceStateChanged(NumericId<Voice> id, Voice::State state)
+{
+    (void)id;
+    (void)state;
+    DBG("Voice " << id.number << ": state " << static_cast<int>(state));
+}
+
 void sfz::Synth::onParseFullBlock(const std::string& header, const std::vector<Opcode>& members)
 {
    switch (hash(header)) {
@ -95,7 +102,8 @@ void sfz::Synth::onParseWarning(const SourceRange& range, const std::string& mes

 void sfz::Synth::buildRegion(const std::vector<Opcode>& regionOpcodes)
 {
-    auto lastRegion = absl::make_unique<Region>(resources.midiState, defaultPath);
+    int regionNumber = static_cast<int>(regions.size());
+    auto lastRegion = absl::make_unique<Region>(regionNumber, resources.midiState, defaultPath);

    auto parseOpcodes = [&](const std::vector<Opcode>& opcodes) {
        for (auto& opcode : opcodes) {
@ -353,22 +361,20 @@ void sfz::Synth::finalizeSfzLoad()
 {
    resources.filePool.setRootDirectory(parser.originalDirectory());

-    auto currentRegion = regions.begin();
-    auto lastRegion = regions.rbegin();
-    auto removeCurrentRegion = [&currentRegion, &lastRegion]() {
-        if (currentRegion->get() == nullptr)
-            return;
+    size_t currentRegionIndex = 0;
+    size_t currentRegionCount = regions.size();

-        DBG("Removing the region with sample " << currentRegion->get()->sampleId);
-        std::iter_swap(currentRegion, lastRegion);
-        ++lastRegion;
+    auto removeCurrentRegion = [this, &currentRegionIndex, &currentRegionCount]() {
+        DBG("Removing the region with sample " << regions[currentRegionIndex]->sampleId);
+        regions.erase(regions.begin() + currentRegionIndex);
+        --currentRegionCount;
    };

    size_t maxFilters { 0 };
    size_t maxEQs { 0 };

-    while (currentRegion < lastRegion.base()) {
-        auto region = currentRegion->get();
+    while (currentRegionIndex < currentRegionCount) {
+        auto region = regions[currentRegionIndex].get();

        if (!region->oscillator && !region->isGenerator()) {
            if (!resources.filePool.checkSampleId(region->sampleId)) {
@ -473,11 +479,10 @@ void sfz::Synth::finalizeSfzLoad()
        maxFilters = max(maxFilters, region->filters.size());
        maxEQs = max(maxEQs, region->equalizers.size());

-        ++currentRegion;
+        ++currentRegionIndex;
    }
-    const auto remainingRegions = std::distance(regions.begin(), lastRegion.base());
-    DBG("Removing " << (regions.size() - remainingRegions) << " out of " << regions.size() << " regions");
-    regions.resize(remainingRegions);
+    DBG("Removing " << (regions.size() - currentRegionCount) << " out of " << regions.size() << " regions");
+    regions.resize(currentRegionCount);
    modificationTime = checkModificationTime();

    for (auto& voice : voices) {
@ -1059,6 +1064,40 @@ const sfz::EffectBus* sfz::Synth::getEffectBusView(int idx) const noexcept
    return (size_t)idx < effectBuses.size() ? effectBuses[idx].get() : nullptr;
 }

+const sfz::Region* sfz::Synth::getRegionById(NumericId<Region> id) const noexcept
+{
+    const size_t size = regions.size();
+
+    if (size == 0 || !id.valid())
+        return nullptr;
+
+    // search a sequence of ordered identifiers with potential gaps
+    size_t index = static_cast<size_t>(id.number);
+    index = std::min(index, size - 1);
+
+    while (index > 0 && regions[index]->getId().number > id.number)
+        --index;
+
+    return (regions[index]->getId() == id) ? regions[index].get() : nullptr;
+}
+
+const sfz::Voice* sfz::Synth::getVoiceById(NumericId<Voice> id) const noexcept
+{
+    const size_t size = voices.size();
+
+    if (size == 0 || !id.valid())
+        return nullptr;
+
+    // search a sequence of ordered identifiers with potential gaps
+    size_t index = static_cast<size_t>(id.number);
+    index = std::min(index, size - 1);
+
+    while (index > 0 && voices[index]->getId().number > id.number)
+        --index;
+
+    return (voices[index]->getId() == id) ? voices[index].get() : nullptr;
+}
+
 const sfz::Voice* sfz::Synth::getVoiceView(int idx) const noexcept
 {
    return (size_t)idx < voices.size() ? voices[idx].get() : nullptr;
@ -1104,8 +1143,11 @@ void sfz::Synth::resetVoices(int numVoices)
    voices.clear();
    voices.reserve(numVoices);

-    for (int i = 0; i < numVoices; ++i)
-        voices.push_back(absl::make_unique<Voice>(resources));
+    for (int i = 0; i < numVoices; ++i) {
+        auto voice = absl::make_unique<Voice>(i, resources);
+        voice->setStateListener(this);
+        voices.emplace_back(std::move(voice));
+    }

    voiceViewArray.clear();
    voiceViewArray.reserve(numVoices);
--- a/src/sfizz/Synth.h
+++ b/src/sfizz/Synth.h
@ -60,7 +60,7 @@ namespace sfz {
 * The jack_client.cpp file contains examples of the most classical usage of the
 * synth and can be used as a reference.
 */
-class Synth final : public Parser::Listener {
+class Synth final : public Voice::StateListener, public Parser::Listener {
 public:
    /**
     * @brief Construct a new Synth object with no voices. If you want sound
@ -184,6 +184,20 @@ public:
     * @brief Export a MIDI Name document describing the loaded instrument
     */
    std::string exportMidnam(absl::string_view model = {}) const;
+    /**
+     * @brief Find the region which is associated with the given identifier.
+     *
+     * @param id
+     * @return const Region*
+     */
+    const Region* getRegionById(NumericId<Region> id) const noexcept;
+    /**
+     * @brief Find the voice which is associated with the given identifier.
+     *
+     * @param id
+     * @return const Voice*
+     */
+    const Voice* getVoiceById(NumericId<Voice> id) const noexcept;
    /**
     * @brief Get a raw view into a specific region. This is mostly used
     * for testing.
@ -499,6 +513,12 @@ public:
     */
    const std::vector<CCNamePair>& getCCLabels() const noexcept { return ccLabels; }

+protected:
+    /**
+     * @brief The voice callback which is called during a change of state.
+     */
+    void onVoiceStateChanged(NumericId<Voice> idNumber, Voice::State state) override;
+
 protected:
    /**
     * @brief The parser callback; this is called by the parent object each time
--- a/src/sfizz/Voice.cpp
+++ b/src/sfizz/Voice.cpp
@ -14,8 +14,8 @@
 #include "Interpolators.h"
 #include "absl/algorithm/container.h"

-sfz::Voice::Voice(sfz::Resources& resources)
-: resources(resources)
+sfz::Voice::Voice(int voiceNumber, sfz::Resources& resources)
+: id{voiceNumber}, stateListener(nullptr), resources(resources)
 {
    filters.reserve(config::filtersPerVoice);
    equalizers.reserve(config::eqsPerVoice);
@ -36,7 +36,7 @@ void sfz::Voice::startVoice(Region* region, int delay, int number, float value,
    triggerValue = value;

    this->region = region;
-    state = State::playing;
+    switchState(State::playing);

    ASSERT(delay >= 0);
    if (delay < 0)
@ -652,7 +652,7 @@ bool sfz::Voice::checkOffGroup(int delay, uint32_t group) noexcept

 void sfz::Voice::reset() noexcept
 {
-    state = State::idle;
+    switchState(State::idle);
    region = nullptr;
    currentPromise.reset();
    sourcePosition = 0;
@ -771,3 +771,13 @@ void sfz::Voice::updateChannelPowers(AudioSpan<float> buffer)
                channelEnvelopeFilters[i].tickLowpass(std::abs(input[s]));
    }
 }
+
+
+void sfz::Voice::switchState(State s)
+{
+    if (s != state) {
+        state = s;
+        if (stateListener)
+            stateListener->onVoiceStateChanged(id, s);
+    }
+}
--- a/src/sfizz/Voice.h
+++ b/src/sfizz/Voice.h
@ -14,6 +14,7 @@
 #include "AudioSpan.h"
 #include "LeakDetector.h"
 #include "OnePoleFilter.h"
+#include "NumericId.h"
 #include "absl/types/span.h"
 #include <memory>
 #include <random>
@ -32,14 +33,39 @@ public:
    /**
     * @brief Construct a new voice with the midistate singleton
     *
+     * @param voiceNumber
     * @param midiState
     */
-    Voice(Resources& resources);
+    Voice(int voiceNumber, Resources& resources);
    enum class TriggerType {
        NoteOn,
        NoteOff,
        CC
    };
+
+    /**
+     * @brief Get the unique identifier of this voice in a synth
+     */
+    NumericId<Voice> getId() const noexcept
+    {
+        return id;
+    }
+
+    enum class State {
+        idle,
+        playing
+    };
+
+    class StateListener {
+    public:
+        virtual void onVoiceStateChanged(NumericId<Voice> /*id*/, State /*state*/) {}
+    };
+
+    /**
+     * @brief Sets the listener which is called when the voice state changes.
+     */
+    void setStateListener(StateListener *l) noexcept { stateListener = l; }
+
    /**
     * @brief Change the sample rate of the voice. This is used to compute all
     * pitch related transformations so it needs to be propagated from the synth
@ -270,12 +296,16 @@ private:
    void setupOscillatorUnison();
    void updateChannelPowers(AudioSpan<float> buffer);

+    /**
+     * @brief Modify the voice state and notify any listeners.
+     */
+    void switchState(State s);
+
+    const NumericId<Voice> id;
+    StateListener* stateListener = nullptr;
+
    Region* region { nullptr };

-    enum class State {
-        idle,
-        playing
-    };
    State state { State::idle };
    bool noteIsOff { false };

--- a/tests/RegionActivationT.cpp
+++ b/tests/RegionActivationT.cpp
@ -13,7 +13,7 @@ using namespace sfz::literals;
 TEST_CASE("Region activation", "Region tests")
 {
    sfz::MidiState midiState;
-    sfz::Region region { midiState };
+    sfz::Region region { 0, midiState };

    region.parseOpcode({ "sample", "*sine" });
    SECTION("Basic state")
--- a/tests/RegionT.cpp
+++ b/tests/RegionT.cpp
@ -14,7 +14,7 @@ using namespace sfz::literals;
 TEST_CASE("[Region] Parsing opcodes")
 {
    sfz::MidiState midiState;
-    sfz::Region region { midiState };
+    sfz::Region region { 0, midiState };

    SECTION("sample")
    {
@ -1672,7 +1672,7 @@ TEST_CASE("[Region] Parsing opcodes")
 TEST_CASE("[Region] Non-conforming floating point values in integer opcodes")
 {
    sfz::MidiState midiState;
-    sfz::Region region { midiState };
+    sfz::Region region { 0, midiState };
    region.parseOpcode({ "offset", "2014.5" });
    REQUIRE(region.offset == 2014);
    region.parseOpcode({ "pitch_keytrack", "-2.1" });
--- a/tests/RegionTriggersT.cpp
+++ b/tests/RegionTriggersT.cpp
@ -13,7 +13,7 @@ using namespace sfz::literals;
 TEST_CASE("Basic triggers", "Region triggers")
 {
    sfz::MidiState midiState;
-    sfz::Region region { midiState };
+    sfz::Region region { 0, midiState };

    region.parseOpcode({ "sample", "*sine" });
    SECTION("key")
@ -130,7 +130,7 @@ TEST_CASE("Basic triggers", "Region triggers")
 TEST_CASE("Legato triggers", "Region triggers")
 {
    sfz::MidiState midiState;
-    sfz::Region region { midiState };
+    sfz::Region region { 0, midiState };
    region.parseOpcode({ "sample", "*sine" });
    SECTION("First note playing")
    {
--- a/tests/RegionValueComputationsT.cpp
+++ b/tests/RegionValueComputationsT.cpp
@ -17,7 +17,7 @@ constexpr int numRandomTests { 64 };
 TEST_CASE("[Region] Crossfade in on key")
 {
 	sfz::MidiState midiState;
-    sfz::Region region { midiState };
+    sfz::Region region { 0, midiState };
    region.parseOpcode({ "sample", "*sine" });
    region.parseOpcode({ "xfin_lokey", "1" });
    region.parseOpcode({ "xfin_hikey", "3" });
@ -29,7 +29,7 @@ TEST_CASE("[Region] Crossfade in on key")
 TEST_CASE("[Region] Crossfade in on key - 2")
 {
 	sfz::MidiState midiState;
-    sfz::Region region { midiState };
+    sfz::Region region { 0, midiState };
    region.parseOpcode({ "sample", "*sine" });
    region.parseOpcode({ "xfin_lokey", "1" });
    region.parseOpcode({ "xfin_hikey", "5" });
@ -44,7 +44,7 @@ TEST_CASE("[Region] Crossfade in on key - 2")
 TEST_CASE("[Region] Crossfade in on key - gain")
 {
 	sfz::MidiState midiState;
-    sfz::Region region { midiState };
+    sfz::Region region { 0, midiState };
    region.parseOpcode({ "sample", "*sine" });
    region.parseOpcode({ "xfin_lokey", "1" });
    region.parseOpcode({ "xfin_hikey", "5" });
@ -59,7 +59,7 @@ TEST_CASE("[Region] Crossfade in on key - gain")
 TEST_CASE("[Region] Crossfade out on key")
 {
 	sfz::MidiState midiState;
-    sfz::Region region { midiState };
+    sfz::Region region { 0, midiState };
    region.parseOpcode({ "sample", "*sine" });
    region.parseOpcode({ "xfout_lokey", "51" });
    region.parseOpcode({ "xfout_hikey", "55" });
@ -75,7 +75,7 @@ TEST_CASE("[Region] Crossfade out on key")
 TEST_CASE("[Region] Crossfade out on key - gain")
 {
 	sfz::MidiState midiState;
-    sfz::Region region { midiState };
+    sfz::Region region { 0, midiState };
    region.parseOpcode({ "sample", "*sine" });
    region.parseOpcode({ "xfout_lokey", "51" });
    region.parseOpcode({ "xfout_hikey", "55" });
@ -92,7 +92,7 @@ TEST_CASE("[Region] Crossfade out on key - gain")
 TEST_CASE("[Region] Crossfade in on velocity")
 {
 	sfz::MidiState midiState;
-    sfz::Region region { midiState };
+    sfz::Region region { 0, midiState };
    region.parseOpcode({ "sample", "*sine" });
    region.parseOpcode({ "xfin_lovel", "20" });
    region.parseOpcode({ "xfin_hivel", "24" });
@ -109,7 +109,7 @@ TEST_CASE("[Region] Crossfade in on velocity")
 TEST_CASE("[Region] Crossfade in on vel - gain")
 {
 	sfz::MidiState midiState;
-    sfz::Region region { midiState };
+    sfz::Region region { 0, midiState };
    region.parseOpcode({ "sample", "*sine" });
    region.parseOpcode({ "xfin_lovel", "20" });
    region.parseOpcode({ "xfin_hivel", "24" });
@ -127,7 +127,7 @@ TEST_CASE("[Region] Crossfade in on vel - gain")
 TEST_CASE("[Region] Crossfade out on vel")
 {
 	sfz::MidiState midiState;
-    sfz::Region region { midiState };
+    sfz::Region region { 0, midiState };
    region.parseOpcode({ "sample", "*sine" });
    region.parseOpcode({ "xfout_lovel", "51" });
    region.parseOpcode({ "xfout_hivel", "55" });
@ -144,7 +144,7 @@ TEST_CASE("[Region] Crossfade out on vel")
 TEST_CASE("[Region] Crossfade out on vel - gain")
 {
 	sfz::MidiState midiState;
-    sfz::Region region { midiState };
+    sfz::Region region { 0, midiState };
    region.parseOpcode({ "sample", "*sine" });
    region.parseOpcode({ "xfout_lovel", "51" });
    region.parseOpcode({ "xfout_hivel", "55" });
@ -162,7 +162,7 @@ TEST_CASE("[Region] Crossfade out on vel - gain")
 TEST_CASE("[Region] Crossfade in on CC")
 {
 	sfz::MidiState midiState;
-    sfz::Region region { midiState };
+    sfz::Region region { 0, midiState };
    region.parseOpcode({ "sample", "*sine" });
    region.parseOpcode({ "xfin_locc24", "20" });
    region.parseOpcode({ "xfin_hicc24", "24" });
@ -186,7 +186,7 @@ TEST_CASE("[Region] Crossfade in on CC")
 TEST_CASE("[Region] Crossfade in on CC - gain")
 {
 	sfz::MidiState midiState;
-    sfz::Region region { midiState };
+    sfz::Region region { 0, midiState };
    region.parseOpcode({ "sample", "*sine" });
    region.parseOpcode({ "xfin_locc24", "20" });
    region.parseOpcode({ "xfin_hicc24", "24" });
@ -210,7 +210,7 @@ TEST_CASE("[Region] Crossfade in on CC - gain")
 TEST_CASE("[Region] Crossfade out on CC")
 {
 	sfz::MidiState midiState;
-    sfz::Region region { midiState };
+    sfz::Region region { 0, midiState };
    region.parseOpcode({ "sample", "*sine" });
    region.parseOpcode({ "xfout_locc24", "20" });
    region.parseOpcode({ "xfout_hicc24", "24" });
@ -234,7 +234,7 @@ TEST_CASE("[Region] Crossfade out on CC")
 TEST_CASE("[Region] Crossfade out on CC - gain")
 {
 	sfz::MidiState midiState;
-    sfz::Region region { midiState };
+    sfz::Region region { 0, midiState };
    region.parseOpcode({ "sample", "*sine" });
    region.parseOpcode({ "xfout_locc24", "20" });
    region.parseOpcode({ "xfout_hicc24", "24" });
@ -259,7 +259,7 @@ TEST_CASE("[Region] Crossfade out on CC - gain")
 TEST_CASE("[Region] Velocity bug for extreme values - veltrack at 0")
 {
    sfz::MidiState midiState;
-    sfz::Region region { midiState };
+    sfz::Region region { 0, midiState };
    region.parseOpcode({ "sample", "*sine" });
    region.parseOpcode({ "amp_veltrack", "0" });
    REQUIRE(region.getNoteGain(64, 127_norm) == 1.0_a);
@ -270,7 +270,7 @@ TEST_CASE("[Region] Velocity bug for extreme values - veltrack at 0")
 TEST_CASE("[Region] Velocity bug for extreme values - positive veltrack")
 {
    sfz::MidiState midiState;
-    sfz::Region region { midiState };
+    sfz::Region region { 0, midiState };
    region.parseOpcode({ "sample", "*sine" });
    region.parseOpcode({ "amp_veltrack", "100" });
    REQUIRE(region.getNoteGain(64, 127_norm) == 1.0_a);
@ -280,7 +280,7 @@ TEST_CASE("[Region] Velocity bug for extreme values - positive veltrack")
 TEST_CASE("[Region] Velocity bug for extreme values - negative veltrack")
 {
    sfz::MidiState midiState;
-    sfz::Region region { midiState };
+    sfz::Region region { 0, midiState };
    region.parseOpcode({ "sample", "*sine" });
    region.parseOpcode({ "amp_veltrack", "-100" });
    REQUIRE(region.getNoteGain(64, 127_norm) == Approx(0.0).margin(0.0001));
@ -291,7 +291,7 @@ TEST_CASE("[Region] rt_decay")
 {
    sfz::MidiState midiState;
    midiState.setSampleRate(1000);
-    sfz::Region region { midiState };
+    sfz::Region region { 0, midiState };
    region.parseOpcode({ "sample", "*sine" });
    region.parseOpcode({ "trigger", "release" });
    region.parseOpcode({ "rt_decay", "10" });
@ -311,7 +311,7 @@ TEST_CASE("[Region] rt_decay")
 TEST_CASE("[Region] Base delay")
 {
    sfz::MidiState midiState;
-    sfz::Region region{ midiState };
+    sfz::Region region { 0, midiState };
    region.parseOpcode({ "sample", "*sine" });
    region.parseOpcode({ "delay", "10" });
    REQUIRE( region.getDelay() == 10.0f );
--- a/tests/SynthT.cpp
+++ b/tests/SynthT.cpp
@ -6,6 +6,7 @@

 #include "sfizz/Synth.h"
 #include "sfizz/SfzHelpers.h"
+#include "sfizz/NumericId.h"
 #include "catch2/catch.hpp"
 using namespace Catch::literals;
 using namespace sfz::literals;
@ -462,3 +463,26 @@ TEST_CASE("[Synth] velcurve")
    REQUIRE( synth.getRegionView(1)->velocityCurve(96_norm) == Approx(0.5f).margin(1e-2) );
    REQUIRE( synth.getRegionView(1)->velocityCurve(127_norm) == 0.0_a );
 }
+
+TEST_CASE("[Synth] Region by identifier")
+{
+    sfz::Synth synth;
+    synth.loadSfzString("regionByIdentifier.sfz", R"(
+<region>sample=*sine
+<region>sample=*sine
+<region>sample=doesNotExist.wav
+<region>sample=*sine
+<region>sample=doesNotExist.wav
+<region>sample=*sine
+)");
+
+    REQUIRE(synth.getNumRegions() == 4);
+    REQUIRE(synth.getRegionView(0) == synth.getRegionById(NumericId<sfz::Region>{0}));
+    REQUIRE(synth.getRegionView(1) == synth.getRegionById(NumericId<sfz::Region>{1}));
+    REQUIRE(nullptr == synth.getRegionById(NumericId<sfz::Region>{2}));
+    REQUIRE(synth.getRegionView(2) == synth.getRegionById(NumericId<sfz::Region>{3}));
+    REQUIRE(nullptr == synth.getRegionById(NumericId<sfz::Region>{4}));
+    REQUIRE(synth.getRegionView(3) == synth.getRegionById(NumericId<sfz::Region>{5}));
+    REQUIRE(nullptr == synth.getRegionById(NumericId<sfz::Region>{6}));
+    REQUIRE(nullptr == synth.getRegionById(NumericId<sfz::Region>{}));
+}