Rename DEFAULT_NUM_INPUTS and DEFAULT_NUM_OUTPUTS

BREAKING_CHANGES.md

@@ -6,6 +6,13 @@ new and what's changed, this document lists all breaking changes in reverse
 chronological order. If a new feature did not require any changes to existing
 code then it will not be listed here.
 
+## [2022-08-19]
+
+- `Plugin::DEFAULT_NUM_INPUTS` and `Plugin::DEFAULT_NUM_OUTPUTS` have been
+  renamed to `Plugin::DEFAULT_INPUT_CHANNELS` and
+  `Plugin::DEFAULT_OUTPUT_CHANNELS` respectively to avoid confusion as these
+  constants only affect the main input and output.
+
 ## [2022-07-18]
 
 - `IntRange` and `FloatRange` no longer have min/max methods and instead have

plugins/crisp/src/lib.rs

@@ -302,8 +302,8 @@ impl Plugin for Crisp {
 
     const VERSION: &'static str = "0.1.0";
 
-    const DEFAULT_NUM_INPUTS: u32 = NUM_CHANNELS;
+    const DEFAULT_INPUT_CHANNELS: u32 = NUM_CHANNELS;
-    const DEFAULT_NUM_OUTPUTS: u32 = NUM_CHANNELS;
+    const DEFAULT_OUTPUT_CHANNELS: u32 = NUM_CHANNELS;
 
     const SAMPLE_ACCURATE_AUTOMATION: bool = true;
 

plugins/crossover/src/lib.rs

@@ -166,8 +166,8 @@ impl Plugin for Crossover {
 
     const VERSION: &'static str = "0.1.0";
 
-    const DEFAULT_NUM_INPUTS: u32 = NUM_CHANNELS;
+    const DEFAULT_INPUT_CHANNELS: u32 = NUM_CHANNELS;
-    const DEFAULT_NUM_OUTPUTS: u32 = NUM_CHANNELS;
+    const DEFAULT_OUTPUT_CHANNELS: u32 = NUM_CHANNELS;
 
     const DEFAULT_AUX_OUTPUTS: Option<AuxiliaryIOConfig> = Some(AuxiliaryIOConfig {
         // Two to five of these busses will be used at a time

plugins/diopser/src/lib.rs

@@ -121,7 +121,7 @@ impl Default for Diopser {
 
         // We only do stereo right now so this is simple
         let (spectrum_input, spectrum_output) =
-            SpectrumInput::new(Self::DEFAULT_NUM_OUTPUTS as usize);
+            SpectrumInput::new(Self::DEFAULT_OUTPUT_CHANNELS as usize);
 
         Self {
             params: Arc::new(DiopserParams::new(should_update_filters.clone())),
@@ -247,8 +247,8 @@ impl Plugin for Diopser {
 
     const VERSION: &'static str = "0.2.0";
 
-    const DEFAULT_NUM_INPUTS: u32 = 2;
+    const DEFAULT_INPUT_CHANNELS: u32 = 2;
-    const DEFAULT_NUM_OUTPUTS: u32 = 2;
+    const DEFAULT_OUTPUT_CHANNELS: u32 = 2;
 
     const SAMPLE_ACCURATE_AUTOMATION: bool = true;
 

plugins/examples/gain/src/lib.rs

@@ -110,8 +110,8 @@ impl Plugin for Gain {
 
     const VERSION: &'static str = "0.0.1";
 
-    const DEFAULT_NUM_INPUTS: u32 = 2;
+    const DEFAULT_INPUT_CHANNELS: u32 = 2;
-    const DEFAULT_NUM_OUTPUTS: u32 = 2;
+    const DEFAULT_OUTPUT_CHANNELS: u32 = 2;
 
     const DEFAULT_AUX_INPUTS: Option<AuxiliaryIOConfig> = None;
     const DEFAULT_AUX_OUTPUTS: Option<AuxiliaryIOConfig> = None;

plugins/examples/gain_gui_egui/src/lib.rs

@@ -75,8 +75,8 @@ impl Plugin for Gain {
 
     const VERSION: &'static str = "0.0.1";
 
-    const DEFAULT_NUM_INPUTS: u32 = 2;
+    const DEFAULT_INPUT_CHANNELS: u32 = 2;
-    const DEFAULT_NUM_OUTPUTS: u32 = 2;
+    const DEFAULT_OUTPUT_CHANNELS: u32 = 2;
 
     const SAMPLE_ACCURATE_AUTOMATION: bool = true;
 

plugins/examples/gain_gui_iced/src/lib.rs

@@ -72,8 +72,8 @@ impl Plugin for Gain {
 
     const VERSION: &'static str = "0.0.1";
 
-    const DEFAULT_NUM_INPUTS: u32 = 2;
+    const DEFAULT_INPUT_CHANNELS: u32 = 2;
-    const DEFAULT_NUM_OUTPUTS: u32 = 2;
+    const DEFAULT_OUTPUT_CHANNELS: u32 = 2;
 
     const SAMPLE_ACCURATE_AUTOMATION: bool = true;
 

plugins/examples/gain_gui_vizia/src/lib.rs

@@ -71,8 +71,8 @@ impl Plugin for Gain {
 
     const VERSION: &'static str = "0.0.1";
 
-    const DEFAULT_NUM_INPUTS: u32 = 2;
+    const DEFAULT_INPUT_CHANNELS: u32 = 2;
-    const DEFAULT_NUM_OUTPUTS: u32 = 2;
+    const DEFAULT_OUTPUT_CHANNELS: u32 = 2;
 
     const SAMPLE_ACCURATE_AUTOMATION: bool = true;
 

plugins/examples/midi_inverter/src/lib.rs

@@ -26,8 +26,8 @@ impl Plugin for MidiInverter {
 
     const VERSION: &'static str = "0.0.1";
 
-    const DEFAULT_NUM_INPUTS: u32 = 0;
+    const DEFAULT_INPUT_CHANNELS: u32 = 0;
-    const DEFAULT_NUM_OUTPUTS: u32 = 0;
+    const DEFAULT_OUTPUT_CHANNELS: u32 = 0;
 
     const MIDI_INPUT: MidiConfig = MidiConfig::MidiCCs;
     const MIDI_OUTPUT: MidiConfig = MidiConfig::MidiCCs;

plugins/examples/poly_mod_synth/src/lib.rs

@@ -148,8 +148,8 @@ impl Plugin for PolyModSynth {
 
     const VERSION: &'static str = "0.0.1";
 
-    const DEFAULT_NUM_INPUTS: u32 = 2;
+    const DEFAULT_INPUT_CHANNELS: u32 = 2;
-    const DEFAULT_NUM_OUTPUTS: u32 = 2;
+    const DEFAULT_OUTPUT_CHANNELS: u32 = 2;
 
     // We won't need any MIDI CCs here, we just want notes and polyphonic modulation
     const MIDI_INPUT: MidiConfig = MidiConfig::Basic;

plugins/examples/sine/src/lib.rs

@@ -105,8 +105,8 @@ impl Plugin for Sine {
 
     const VERSION: &'static str = "0.0.1";
 
-    const DEFAULT_NUM_INPUTS: u32 = 0;
+    const DEFAULT_INPUT_CHANNELS: u32 = 0;
-    const DEFAULT_NUM_OUTPUTS: u32 = 2;
+    const DEFAULT_OUTPUT_CHANNELS: u32 = 2;
 
     const MIDI_INPUT: MidiConfig = MidiConfig::Basic;
     const SAMPLE_ACCURATE_AUTOMATION: bool = true;

plugins/examples/stft/src/lib.rs

@@ -90,8 +90,8 @@ impl Plugin for Stft {
 
     const VERSION: &'static str = "0.0.1";
 
-    const DEFAULT_NUM_INPUTS: u32 = 2;
+    const DEFAULT_INPUT_CHANNELS: u32 = 2;
-    const DEFAULT_NUM_OUTPUTS: u32 = 2;
+    const DEFAULT_OUTPUT_CHANNELS: u32 = 2;
 
     const SAMPLE_ACCURATE_AUTOMATION: bool = true;
 

plugins/loudness_war_winner/src/lib.rs

@@ -120,8 +120,8 @@ impl Plugin for LoudnessWarWinner {
 
     const VERSION: &'static str = "0.1.0";
 
-    const DEFAULT_NUM_INPUTS: u32 = 2;
+    const DEFAULT_INPUT_CHANNELS: u32 = 2;
-    const DEFAULT_NUM_OUTPUTS: u32 = 2;
+    const DEFAULT_OUTPUT_CHANNELS: u32 = 2;
 
     fn params(&self) -> Arc<dyn Params> {
         self.params.clone()

plugins/puberty_simulator/src/lib.rs

@@ -165,8 +165,8 @@ impl Plugin for PubertySimulator {
 
     const VERSION: &'static str = "0.1.0";
 
-    const DEFAULT_NUM_INPUTS: u32 = 2;
+    const DEFAULT_INPUT_CHANNELS: u32 = 2;
-    const DEFAULT_NUM_OUTPUTS: u32 = 2;
+    const DEFAULT_OUTPUT_CHANNELS: u32 = 2;
 
     fn params(&self) -> Arc<dyn Params> {
         self.params.clone()

plugins/safety_limiter/src/lib.rs

@@ -154,8 +154,8 @@ impl Plugin for SafetyLimiter {
 
     const VERSION: &'static str = "0.1.0";
 
-    const DEFAULT_NUM_INPUTS: u32 = 2;
+    const DEFAULT_INPUT_CHANNELS: u32 = 2;
-    const DEFAULT_NUM_OUTPUTS: u32 = 2;
+    const DEFAULT_OUTPUT_CHANNELS: u32 = 2;
 
     fn params(&self) -> Arc<dyn Params> {
         self.params.clone()

plugins/spectral_compressor/src/lib.rs

@@ -137,7 +137,7 @@ impl Default for SpectralCompressor {
         // Changing any of the compressor threshold or ratio parameters will set an atomic flag in
         // this object that causes the compressor thresholds and ratios to be recalcualted
         let compressor_bank = compressor_bank::CompressorBank::new(
-            Self::DEFAULT_NUM_OUTPUTS as usize,
+            Self::DEFAULT_OUTPUT_CHANNELS as usize,
             MAX_WINDOW_SIZE,
         );
 
@@ -153,7 +153,7 @@ impl Default for SpectralCompressor {
             },
 
             // These three will be set to the correct values in the initialize function
-            stft: util::StftHelper::new(Self::DEFAULT_NUM_OUTPUTS as usize, MAX_WINDOW_SIZE, 0),
+            stft: util::StftHelper::new(Self::DEFAULT_OUTPUT_CHANNELS as usize, MAX_WINDOW_SIZE, 0),
             window_function: Vec::with_capacity(MAX_WINDOW_SIZE),
             dry_wet_mixer: dry_wet_mixer::DryWetMixer::new(0, 0, 0),
             compressor_bank,
@@ -261,8 +261,8 @@ impl Plugin for SpectralCompressor {
 
     const VERSION: &'static str = "0.2.0";
 
-    const DEFAULT_NUM_INPUTS: u32 = 2;
+    const DEFAULT_INPUT_CHANNELS: u32 = 2;
-    const DEFAULT_NUM_OUTPUTS: u32 = 2;
+    const DEFAULT_OUTPUT_CHANNELS: u32 = 2;
     const DEFAULT_AUX_INPUTS: Option<AuxiliaryIOConfig> = Some(AuxiliaryIOConfig {
         num_busses: 1,
         num_channels: 2,

src/plugin.rs

@@ -40,20 +40,20 @@ pub trait Plugin: Default + Send + Sync + 'static {
     /// the defaults instead of setting up the busses properly.
     ///
     /// Setting this to zero causes the plugin to have no main input bus.
-    const DEFAULT_NUM_INPUTS: u32 = 2;
+    const DEFAULT_INPUT_CHANNELS: u32 = 2;
     /// The default number of output channels. All of the same caveats mentioned for
-    /// `DEFAULT_NUM_INPUTS` apply here.
+    /// `DEFAULT_INPUT_CHANNELS` apply here.
     ///
     /// Setting this to zero causes the plugin to have no main output bus.
-    const DEFAULT_NUM_OUTPUTS: u32 = 2;
+    const DEFAULT_OUTPUT_CHANNELS: u32 = 2;
 
     /// If set, then the plugin will have this many sidechain input busses with a default number of
     /// channels. Not all hosts support more than one sidechain input bus. Negotiating the actual
-    /// configuration wroks the same was as with `DEFAULT_NUM_INPUTS`.
+    /// configuration works the same was as with `DEFAULT_INPUT_CHANNELS`.
     const DEFAULT_AUX_INPUTS: Option<AuxiliaryIOConfig> = None;
     /// If set, then the plugin will have this many auxiliary output busses with a default number of
     /// channels. Negotiating the actual configuration wroks the same was as with
-    /// `DEFAULT_NUM_INPUTS`.
+    /// `DEFAULT_INPUT_CHANNELS`.
     const DEFAULT_AUX_OUTPUTS: Option<AuxiliaryIOConfig> = None;
 
     /// Optional names for the main and auxiliary input and output ports. Will be generated if not
@@ -107,8 +107,8 @@ pub trait Plugin: Default + Send + Sync + 'static {
     /// Whether the plugin supports a bus config. This only acts as a check, and the plugin
     /// shouldn't do anything beyond returning true or false.
     fn accepts_bus_config(&self, config: &BusConfig) -> bool {
-        config.num_input_channels == Self::DEFAULT_NUM_INPUTS
+        config.num_input_channels == Self::DEFAULT_INPUT_CHANNELS
-            && config.num_output_channels == Self::DEFAULT_NUM_OUTPUTS
+            && config.num_output_channels == Self::DEFAULT_OUTPUT_CHANNELS
     }
 
     /// Initialize the plugin for the given bus and buffer configurations. These configurations will

src/wrapper/clap/wrapper.rs

@@ -506,8 +506,8 @@ impl<P: ClapPlugin> Wrapper<P> {
         // In the off chance that the default config specified by the plugin is not in the above
         // list, we'll try that as well.
         let default_bus_config = BusConfig {
-            num_input_channels: P::DEFAULT_NUM_INPUTS,
+            num_input_channels: P::DEFAULT_INPUT_CHANNELS,
-            num_output_channels: P::DEFAULT_NUM_OUTPUTS,
+            num_output_channels: P::DEFAULT_OUTPUT_CHANNELS,
             aux_input_busses: P::DEFAULT_AUX_INPUTS.unwrap_or_default(),
             aux_output_busses: P::DEFAULT_AUX_OUTPUTS.unwrap_or_default(),
         };
@@ -549,8 +549,8 @@ impl<P: ClapPlugin> Wrapper<P> {
 
             is_processing: AtomicBool::new(false),
             current_bus_config: AtomicCell::new(BusConfig {
-                num_input_channels: P::DEFAULT_NUM_INPUTS,
+                num_input_channels: P::DEFAULT_INPUT_CHANNELS,
-                num_output_channels: P::DEFAULT_NUM_OUTPUTS,
+                num_output_channels: P::DEFAULT_OUTPUT_CHANNELS,
                 aux_input_busses: P::DEFAULT_AUX_INPUTS.unwrap_or_default(),
                 aux_output_busses: P::DEFAULT_AUX_OUTPUTS.unwrap_or_default(),
             }),

src/wrapper/vst3/inner.rs

@@ -289,8 +289,8 @@ impl<P: Vst3Plugin> WrapperInner<P> {
             // that, we'll always initialize this configuration even before the host requests a
             // channel layout.
             current_bus_config: AtomicCell::new(BusConfig {
-                num_input_channels: P::DEFAULT_NUM_INPUTS,
+                num_input_channels: P::DEFAULT_INPUT_CHANNELS,
-                num_output_channels: P::DEFAULT_NUM_OUTPUTS,
+                num_output_channels: P::DEFAULT_OUTPUT_CHANNELS,
                 aux_input_busses: P::DEFAULT_AUX_INPUTS.unwrap_or_default(),
                 aux_output_busses: P::DEFAULT_AUX_OUTPUTS.unwrap_or_default(),
             }),

src/wrapper/vst3/wrapper.rs

@@ -91,7 +91,7 @@ impl<P: Vst3Plugin> IComponent for Wrapper<P> {
         // HACK: Bitwig will not call the process function at all if the plugin does not have any
         //       audio IO, so we'll add a zero channel output to work around this if that is the
         //       case
-        let no_main_audio_io = P::DEFAULT_NUM_INPUTS == 0 && P::DEFAULT_NUM_OUTPUTS == 0;
+        let no_main_audio_io = P::DEFAULT_INPUT_CHANNELS == 0 && P::DEFAULT_OUTPUT_CHANNELS == 0;
 
         // A plugin has a main input and output bus if the default number of channels is non-zero,
         // and a plugin can also have auxiliary input and output busses
@@ -99,7 +99,7 @@ impl<P: Vst3Plugin> IComponent for Wrapper<P> {
             x if x == vst3_sys::vst::MediaTypes::kAudio as i32
                 && dir == vst3_sys::vst::BusDirections::kInput as i32 =>
             {
-                let main_busses = if P::DEFAULT_NUM_INPUTS > 0 { 1 } else { 0 };
+                let main_busses = if P::DEFAULT_INPUT_CHANNELS > 0 { 1 } else { 0 };
                 let aux_busses = P::DEFAULT_AUX_INPUTS.unwrap_or_default().num_busses as i32;
 
                 main_busses + aux_busses
@@ -107,7 +107,7 @@ impl<P: Vst3Plugin> IComponent for Wrapper<P> {
             x if x == vst3_sys::vst::MediaTypes::kAudio as i32
                 && dir == vst3_sys::vst::BusDirections::kOutput as i32 =>
             {
-                let main_busses = if P::DEFAULT_NUM_OUTPUTS > 0 { 1 } else { 0 };
+                let main_busses = if P::DEFAULT_OUTPUT_CHANNELS > 0 { 1 } else { 0 };
                 let aux_busses = P::DEFAULT_AUX_OUTPUTS.unwrap_or_default().num_busses as i32;
 
                 if no_main_audio_io {
@@ -144,7 +144,7 @@ impl<P: Vst3Plugin> IComponent for Wrapper<P> {
         // HACK: Bitwig will not call the process function at all if the plugin does not have any
         //       audio IO, so we'll add a zero channel output to work around this if that is the
         //       case
-        let no_main_audio_io = P::DEFAULT_NUM_INPUTS == 0 && P::DEFAULT_NUM_OUTPUTS == 0;
+        let no_main_audio_io = P::DEFAULT_INPUT_CHANNELS == 0 && P::DEFAULT_OUTPUT_CHANNELS == 0;
 
         match (type_, dir, index) {
             (t, _, _) if t == vst3_sys::vst::MediaTypes::kAudio as i32 => {
@@ -159,7 +159,7 @@ impl<P: Vst3Plugin> IComponent for Wrapper<P> {
                 let bus_config = self.inner.current_bus_config.load();
                 if dir == vst3_sys::vst::BusDirections::kInput as i32 {
                     let aux_inputs_only =
-                        P::DEFAULT_NUM_INPUTS == 0 && P::DEFAULT_AUX_INPUTS.is_some();
+                        P::DEFAULT_INPUT_CHANNELS == 0 && P::DEFAULT_AUX_INPUTS.is_some();
                     let aux_input_start_idx = if aux_inputs_only { 0 } else { 1 };
                     if !aux_inputs_only && index == 0 {
                         info.bus_type = vst3_sys::vst::BusTypes::kMain as i32;
@@ -197,7 +197,7 @@ impl<P: Vst3Plugin> IComponent for Wrapper<P> {
                     }
                 } else if dir == vst3_sys::vst::BusDirections::kOutput as i32 {
                     let aux_outputs_only =
-                        P::DEFAULT_NUM_OUTPUTS == 0 && P::DEFAULT_AUX_OUTPUTS.is_some();
+                        P::DEFAULT_OUTPUT_CHANNELS == 0 && P::DEFAULT_AUX_OUTPUTS.is_some();
                     let aux_output_start_idx = if aux_outputs_only { 0 } else { 1 };
                     if (!aux_outputs_only || no_main_audio_io) && index == 0 {
                         info.bus_type = vst3_sys::vst::BusTypes::kMain as i32;
@@ -291,8 +291,8 @@ impl<P: Vst3Plugin> IComponent for Wrapper<P> {
             (t, 0)
                 if t == vst3_sys::vst::MediaTypes::kAudio as i32
                     // We only have an IO pair when the plugin has both a main input and a main output
-                    && P::DEFAULT_NUM_INPUTS > 0
+                    && P::DEFAULT_INPUT_CHANNELS > 0
-                    && P::DEFAULT_NUM_OUTPUTS > 0 =>
+                    && P::DEFAULT_OUTPUT_CHANNELS > 0 =>
             {
                 out_info.media_type = vst3_sys::vst::MediaTypes::kAudio as i32;
                 out_info.bus_index = in_info.bus_index;
@@ -325,7 +325,7 @@ impl<P: Vst3Plugin> IComponent for Wrapper<P> {
         // HACK: Bitwig will not call the process function at all if the plugin does not have any
         //       audio IO, so we'll add a zero channel output to work around this if that is the
         //       case
-        let no_main_audio_io = P::DEFAULT_NUM_INPUTS == 0 && P::DEFAULT_NUM_OUTPUTS == 0;
+        let no_main_audio_io = P::DEFAULT_INPUT_CHANNELS == 0 && P::DEFAULT_OUTPUT_CHANNELS == 0;
 
         // We don't need any special handling here
         match (type_, dir, index) {
@@ -333,7 +333,7 @@ impl<P: Vst3Plugin> IComponent for Wrapper<P> {
                 if t == vst3_sys::vst::MediaTypes::kAudio as i32
                     && d == vst3_sys::vst::BusDirections::kInput as i32 =>
             {
-                let main_busses = if P::DEFAULT_NUM_INPUTS > 0 { 1 } else { 0 };
+                let main_busses = if P::DEFAULT_INPUT_CHANNELS > 0 { 1 } else { 0 };
                 let aux_busses = P::DEFAULT_AUX_INPUTS.unwrap_or_default().num_busses as i32;
 
                 if (0..main_busses + aux_busses).contains(&index) {
@@ -346,7 +346,7 @@ impl<P: Vst3Plugin> IComponent for Wrapper<P> {
                 if t == vst3_sys::vst::MediaTypes::kAudio as i32
                     && d == vst3_sys::vst::BusDirections::kOutput as i32 =>
             {
-                let main_busses = if P::DEFAULT_NUM_OUTPUTS > 0 || no_main_audio_io {
+                let main_busses = if P::DEFAULT_OUTPUT_CHANNELS > 0 || no_main_audio_io {
                     1
                 } else {
                     0
@@ -785,7 +785,7 @@ impl<P: Vst3Plugin> IAudioProcessor for Wrapper<P> {
         // HACK: Bitwig will not call the process function at all if the plugin does not have any
         //       audio IO, so we'll add a zero channel output to work around this if that is the
         //       case
-        let no_main_audio_io = P::DEFAULT_NUM_INPUTS == 0 && P::DEFAULT_NUM_OUTPUTS == 0;
+        let no_main_audio_io = P::DEFAULT_INPUT_CHANNELS == 0 && P::DEFAULT_OUTPUT_CHANNELS == 0;
 
         // Why are these signed integers again?
         if num_ins < 0 || num_outs < 0 {
@@ -796,7 +796,7 @@ impl<P: Vst3Plugin> IAudioProcessor for Wrapper<P> {
         // support plugins with no main IO but with auxiliary IO, we'll need to take that into
         // account when asserting this. If that's the case, then the first bus for that direction
         // will have been marked auxiliary.
-        let aux_inputs_only = P::DEFAULT_NUM_INPUTS == 0 && P::DEFAULT_AUX_INPUTS.is_some();
+        let aux_inputs_only = P::DEFAULT_INPUT_CHANNELS == 0 && P::DEFAULT_AUX_INPUTS.is_some();
         let num_input_channels = if aux_inputs_only || num_ins < 1 {
             0
         } else {
@@ -819,7 +819,7 @@ impl<P: Vst3Plugin> IAudioProcessor for Wrapper<P> {
             }
         }
 
-        let aux_outputs_only = P::DEFAULT_NUM_OUTPUTS == 0 && P::DEFAULT_AUX_OUTPUTS.is_some();
+        let aux_outputs_only = P::DEFAULT_OUTPUT_CHANNELS == 0 && P::DEFAULT_AUX_OUTPUTS.is_some();
         let num_output_channels = if (aux_outputs_only && !no_main_audio_io) || num_outs < 1 {
             0
         } else {
@@ -879,7 +879,7 @@ impl<P: Vst3Plugin> IAudioProcessor for Wrapper<P> {
         // HACK: Bitwig will not call the process function at all if the plugin does not have any
         //       audio IO, so we'll add a zero channel output to work around this if that is the
         //       case
-        let no_main_audio_io = P::DEFAULT_NUM_INPUTS == 0 && P::DEFAULT_NUM_OUTPUTS == 0;
+        let no_main_audio_io = P::DEFAULT_INPUT_CHANNELS == 0 && P::DEFAULT_OUTPUT_CHANNELS == 0;
 
         let channel_count_to_map = |count| match count {
             0 => vst3_sys::vst::kEmpty,
@@ -900,7 +900,7 @@ impl<P: Vst3Plugin> IAudioProcessor for Wrapper<P> {
 
         let bus_config = self.inner.current_bus_config.load();
         let num_channels = if dir == vst3_sys::vst::BusDirections::kInput as i32 {
-            let aux_inputs_only = P::DEFAULT_NUM_INPUTS == 0 && P::DEFAULT_AUX_INPUTS.is_some();
+            let aux_inputs_only = P::DEFAULT_INPUT_CHANNELS == 0 && P::DEFAULT_AUX_INPUTS.is_some();
             let aux_input_start_idx = if aux_inputs_only { 0 } else { 1 };
             if !aux_inputs_only && index == 0 {
                 bus_config.num_input_channels
@@ -913,7 +913,7 @@ impl<P: Vst3Plugin> IAudioProcessor for Wrapper<P> {
                 return kInvalidArgument;
             }
         } else if dir == vst3_sys::vst::BusDirections::kOutput as i32 {
-            let aux_outputs_only = P::DEFAULT_NUM_OUTPUTS == 0 && P::DEFAULT_AUX_OUTPUTS.is_some();
+            let aux_outputs_only = P::DEFAULT_OUTPUT_CHANNELS == 0 && P::DEFAULT_AUX_OUTPUTS.is_some();
             let aux_output_start_idx = if aux_outputs_only { 0 } else { 1 };
             if (!aux_outputs_only || no_main_audio_io) && index == 0 {
                 bus_config.num_output_channels