Redo dither method choices in Quality preferences

src/SampleFormat.cpp

@@ -44,6 +44,7 @@
 #include "Prefs.h"
 #include "Dither.h"
 #include "Internat.h"
+#include "prefs/QualityPrefs.h"
 
 static DitherType gLowQualityDither = DitherType::none;
 static DitherType gHighQualityDither = DitherType::none;
@@ -52,11 +53,8 @@ static Dither gDitherAlgorithm;
 void InitDitherers()
 {
    // Read dither preferences
-   gLowQualityDither = (DitherType)
+   gLowQualityDither = QualityPrefs::FastDitherChoice();
-   gPrefs->Read(wxT("/Quality/DitherAlgorithm"), (long)DitherType::none);
+   gHighQualityDither = QualityPrefs::BestDitherChoice();
-
-   gHighQualityDither = (DitherType)
-   gPrefs->Read(wxT("/Quality/HQDitherAlgorithm"), (long)DitherType::shaped);
 }
 
 const wxChar *GetSampleFormatStr(sampleFormat format)

src/prefs/QualityPrefs.cpp

@@ -55,6 +55,44 @@ static EncodedEnumSetting formatSetting{
    wxT("/SamplingRate/DefaultProjectSampleFormat"),
 };
 
+//////////
+static const IdentInterfaceSymbol choicesDither[] = {
+   { XO("None") },
+   { XO("Rectangle") },
+   { XO("Triangle") },
+   { XO("Shaped") },
+};
+static const size_t nChoicesDither = WXSIZEOF( choicesDither );
+static const int intChoicesDither[] = {
+   (int) DitherType::none,
+   (int) DitherType::rectangle,
+   (int) DitherType::triangle,
+   (int) DitherType::shaped,
+};
+static_assert(
+   nChoicesDither == WXSIZEOF( intChoicesDither ),
+   "size mismatch"
+);
+
+static const int defaultFastDither = 0; // none
+
+static EncodedEnumSetting fastDitherSetting{
+   wxT("Quality/DitherAlgorithmChoice"),
+   choicesDither, nChoicesDither, defaultFastDither,
+   intChoicesDither,
+   wxT("Quality/DitherAlgorithm")
+};
+
+static const int defaultBestDither = 3; // shaped
+
+static EncodedEnumSetting bestDitherSetting{
+   wxT("Quality/HQDitherAlgorithmChoice"),
+   choicesDither, nChoicesDither, defaultBestDither,
+
+   intChoicesDither,
+   wxT("Quality/HQDitherAlgorithm")
+};
+
 //////////
 BEGIN_EVENT_TABLE(QualityPrefs, PrefsPanel)
    EVT_CHOICE(ID_SAMPLE_RATE_CHOICE, QualityPrefs::OnSampleRateChoice)
@@ -97,12 +135,6 @@ void QualityPrefs::Populate()
 /// The corresponding labels are what gets stored.
 void QualityPrefs::GetNamesAndLabels()
 {
-   //------------ Dither Names
-   mDitherNames.Add(_("None"));        mDitherLabels.push_back((int) DitherType::none);
-   mDitherNames.Add(_("Rectangle"));   mDitherLabels.push_back((int) DitherType::rectangle);
-   mDitherNames.Add(_("Triangle"));    mDitherLabels.push_back((int) DitherType::triangle);
-   mDitherNames.Add(_("Shaped"));      mDitherLabels.push_back((int) DitherType::shaped);
-
    //------------ Sample Rate Names
    // JKC: I don't understand the following comment.
    //      Can someone please explain or correct it?
@@ -178,10 +210,7 @@ void QualityPrefs::PopulateOrExchange(ShuttleGui & S)
 
          /* i18n-hint: technical term for randomization to reduce undesirable resampling artifacts */
          S.TieChoice(_("&Dither:"),
-                     wxT("/Quality/DitherAlgorithm"),
+                     fastDitherSetting);
-                     (int) DitherType::none,
-                     mDitherNames,
-                     mDitherLabels);
       }
       S.EndMultiColumn();
    }
@@ -196,10 +225,7 @@ void QualityPrefs::PopulateOrExchange(ShuttleGui & S)
 
          /* i18n-hint: technical term for randomization to reduce undesirable resampling artifacts */
          S.TieChoice(_("Dit&her:"),
-                     wxT("/Quality/HQDitherAlgorithm"),
+                     bestDitherSetting);
-                     (int) DitherType::shaped,
-                     mDitherNames,
-                     mDitherLabels);
       }
       S.EndMultiColumn();
    }
@@ -250,3 +276,13 @@ sampleFormat QualityPrefs::SampleFormatChoice()
    return (sampleFormat)formatSetting.ReadInt();
 }
 
+DitherType QualityPrefs::FastDitherChoice()
+{
+   return (DitherType) fastDitherSetting.ReadInt();
+}
+
+DitherType QualityPrefs::BestDitherChoice()
+{
+   return (DitherType) bestDitherSetting.ReadInt();
+}
+

src/prefs/QualityPrefs.h

@@ -37,13 +37,14 @@ class QualityPrefs final : public PrefsPanel
 
    static sampleFormat SampleFormatChoice();
 
+   static DitherType FastDitherChoice();
+   static DitherType BestDitherChoice();
+
  private:
    void Populate();
    void GetNamesAndLabels();
    void OnSampleRateChoice(wxCommandEvent & e);
 
-   wxArrayString mDitherNames;
-   std::vector<int> mDitherLabels;
    wxArrayString mSampleRateNames;
    std::vector<int> mSampleRateLabels;