Add initial channel InterpolationMethod setting

oxisynth/src/core/channel_pool/channel.rs

@@ -4,24 +4,11 @@ use std::sync::Arc;
 use super::super::soundfont::{Preset, SoundFont};
 
 use crate::arena::Index;
+use crate::core::InterpolationMethod;
 use crate::midi_event::ControlFunction;
 use crate::GeneratorType;
 use crate::Tuning;
 
-// Flags to choose the interpolation method
-#[derive(Default, Debug, Clone, Copy, PartialEq, Eq, Hash)]
-pub enum InterpolationMethod {
-    /// No interpolation: Fastest, but questionable audio quality
-    None = 0,
-    /// Straight-line interpolation: A bit slower, reasonable audio quality
-    Linear = 1,
-    /// Fourth-order interpolation: Requires 50% of the whole DSP processing time, good quality (default)
-    #[default]
-    FourthOrder = 4,
-    /// Seventh-order interpolation
-    SeventhOrder = 7,
-}
-
 #[derive(Clone)]
 struct CcList([u8; 128]);
 
@@ -106,7 +93,7 @@ impl Channel {
             cc: CcList([0; 128]),
             bank_msb: 0,
 
-            interp_method: Default::default(),
+            interp_method: InterpolationMethod::default(),
             tuning: None,
 
             nrpn_select: 0,

oxisynth/src/core/channel_pool/mod.rs

@@ -1,14 +1,23 @@
 mod channel;
-pub use channel::{Channel, InterpolationMethod};
+pub(crate) use channel::Channel;
 
 use crate::OxiError;
 
+use super::InterpolationMethod;
+
 pub struct ChannelPool(Vec<Channel>);
 
 impl ChannelPool {
-    pub fn new(len: usize) -> Self {
-        let channels = (0..len).map(Channel::new).collect();
-        Self(channels)
+    pub fn new(len: usize, interpolation: InterpolationMethod) -> Self {
+        Self(
+            (0..len)
+                .map(|id| {
+                    let mut ch = Channel::new(id);
+                    ch.set_interp_method(interpolation);
+                    ch
+                })
+                .collect(),
+        )
     }
 
     pub fn get(&self, id: usize) -> Result<&Channel, OxiError> {

oxisynth/src/core/mod.rs

@@ -7,7 +7,7 @@ mod settings;
 mod voice_pool;
 
 mod conv;
-pub use channel_pool::InterpolationMethod;
+pub use settings::InterpolationMethod;
 pub(crate) use settings::Settings;
 
 mod font_bank;
@@ -65,7 +65,7 @@ impl Core {
 
             font_bank: FontBank::new(),
 
-            channels: ChannelPool::new(settings.midi_channels as usize),
+            channels: ChannelPool::new(settings.midi_channels as usize, settings.interpolation),
             voices: VoicePool::new(settings.polyphony as usize, settings.sample_rate),
 
             output: OutputBuffer::new(nbuf as usize),

oxisynth/src/core/settings.rs

@@ -1,10 +1,29 @@
 use crate::{RangeError, SettingsError, SynthDescriptor};
 
+// Flags to choose the interpolation method
+#[derive(Default, Debug, Clone, Copy, PartialEq, Eq, Hash)]
+pub enum InterpolationMethod {
+    /// No interpolation: Fastest, but questionable audio quality
+    None = 0,
+    /// Straight-line interpolation: A bit slower, reasonable audio quality
+    Linear = 1,
+    /// Fourth-order interpolation: Requires 50% of the whole DSP processing time, good quality (default)
+    #[default]
+    FourthOrder = 4,
+    /// Seventh-order interpolation
+    SeventhOrder = 7,
+}
+
 pub(crate) struct Settings {
     pub reverb_active: bool,
     pub chorus_active: bool,
     pub drums_channel_active: bool,
 
+    /// Interpolation method/quality
+    //
+    /// Def: FourthOrder
+    pub interpolation: InterpolationMethod,
+
     /// Def: 256
     /// Min: 1
     /// Max: 65535
@@ -122,6 +141,7 @@ impl TryFrom<SynthDescriptor> for Settings {
             reverb_active: desc.reverb_active,
             chorus_active: desc.chorus_active,
             drums_channel_active: desc.drums_channel_active,
+            interpolation: desc.interpolation,
 
             polyphony,
             midi_channels,

oxisynth/src/core/voice_pool/voice/mod.rs

@@ -5,26 +5,23 @@ pub use envelope::EnvelopeStep;
 use envelope::{Envelope, EnvelopePortion};
 
 use crate::{
-    core::{BUFSIZE, BUFSIZE_F32},
+    core::{
+        channel_pool::Channel,
+        conv::{
+            act2hz, atten2amp, cb2amp, ct2hz, ct2hz_real, pan, tc2sec, tc2sec_attack, tc2sec_delay,
+            tc2sec_release,
+        },
+        soundfont::{
+            generator::{Generator, GeneratorList, GeneratorType},
+            modulator::Mod,
+            Sample,
+        },
+        write::FxBuf,
+        InterpolationMethod, BUFSIZE, BUFSIZE_F32,
+    },
     midi_event::ControlFunction,
 };
 
-use super::super::{
-    channel_pool::{Channel, InterpolationMethod},
-    write::FxBuf,
-};
-
-use super::super::soundfont::{
-    generator::{Generator, GeneratorList, GeneratorType},
-    modulator::Mod,
-    Sample,
-};
-
-use super::super::conv::{
-    act2hz, atten2amp, cb2amp, ct2hz, ct2hz_real, pan, tc2sec, tc2sec_attack, tc2sec_delay,
-    tc2sec_release,
-};
-
 use soundfont::raw::{ControllerPalette, GeneralPalette};
 
 type Phase = u64;

oxisynth/src/lib.rs

@@ -17,7 +17,7 @@ mod midi_event;
 mod unsafe_stuff;
 
 pub use api::Tuning;
-pub use core::{GeneratorType, Preset, SoundFont};
+pub use core::{GeneratorType, InterpolationMethod, Preset, SoundFont};
 pub use error::{OxiError, RangeError, SettingsError};
 pub use midi_event::MidiEvent;
 
@@ -34,6 +34,8 @@ pub struct SynthDescriptor {
     pub reverb_active: bool,
     pub chorus_active: bool,
     pub drums_channel_active: bool,
+    // Interpolation method/quality
+    pub interpolation: InterpolationMethod,
 
     /// Def: 256
     /// Min: 1
@@ -71,6 +73,7 @@ impl Default for SynthDescriptor {
             reverb_active: true,
             chorus_active: true,
             drums_channel_active: true,
+            interpolation: InterpolationMethod::default(),
 
             polyphony: 256,
             midi_channels: 16,