From 13369e40852b4e38b7b1f240aaad4a80979f1350 Mon Sep 17 00:00:00 2001
From: Robbert van der Helm <mail@robbertvanderhelm.nl>
Date: Wed, 2 Feb 2022 15:39:55 +0100
Subject: [PATCH] Reinitialize the plugin after restoring state
This lets you use the parameters to set fields on the plugin struct
during `initialize()`.
---
src/plugin.rs | 6 ++++--
src/wrapper/vst3.rs | 16 ++++++++++++++++
2 files changed, 20 insertions(+), 2 deletions(-)
diff --git a/src/plugin.rs b/src/plugin.rs
index 2c8e4295..53771cb9 100644
--- a/src/plugin.rs
+++ b/src/plugin.rs
@@ -87,7 +87,9 @@ pub trait Plugin: Default + Send + Sync {
/// Process audio. To not have to worry about aliasing, the host's input buffer have already
/// been copied to the output buffers if they are not handling buffers in place (most hosts do
- /// however). All channels are also guarenteed to contain the same number of samples.
+ /// however). All channels are also guarenteed to contain the same number of samples. Depending
+ /// on how the host restores plugin state, this function may also be called twice in rapid
+ /// succession.
///
/// TODO: Provide a way to access auxiliary input channels if the IO configuration is
/// assymetric
@@ -117,7 +119,7 @@ pub struct BusConfig {
}
/// Configuration for (the host's) audio buffers.
-#[derive(Debug, Clone, PartialEq)]
+#[derive(Debug, Clone, Copy, PartialEq)]
pub struct BufferConfig {
/// The current sample rate.
pub sample_rate: f32,
diff --git a/src/wrapper/vst3.rs b/src/wrapper/vst3.rs
index d25a9312..550cf6d8 100644
--- a/src/wrapper/vst3.rs
+++ b/src/wrapper/vst3.rs
@@ -107,6 +107,9 @@ struct WrapperInner<'a, P: Plugin> {
is_processing: AtomicBool,
/// The current bus configuration, modified through `IAudioProcessor::setBusArrangements()`.
current_bus_config: AtomicCell<BusConfig>,
+ /// The current buffer configuration, containing the sample rate and the maximum block size.
+ /// Will be set in `IAudioProcessor::setupProcessing()`.
+ current_buffer_config: AtomicCell<Option<BufferConfig>>,
/// Whether the plugin is currently bypassed. This is not yet integrated with the `Plugin`
/// trait.
bypass_state: AtomicBool,
@@ -195,6 +198,7 @@ impl<P: Plugin> WrapperInner<'_, P> {
num_input_channels: P::DEFAULT_NUM_INPUTS,
num_output_channels: P::DEFAULT_NUM_OUTPUTS,
}),
+ current_buffer_config: AtomicCell::new(None),
bypass_state: AtomicBool::new(false),
last_process_status: AtomicCell::new(ProcessStatus::Normal),
current_latency: AtomicU32::new(0),
@@ -520,6 +524,15 @@ impl<P: Plugin> IComponent for Wrapper<'_, P> {
.params()
.deserialize_fields(&state.fields);
+ // Reinitialize the plugin after loading state so it can respond to the new parmaeters
+ let bus_config = self.inner.current_bus_config.load();
+ if let Some(buffer_config) = self.inner.current_buffer_config.load() {
+ self.inner
+ .plugin
+ .write()
+ .initialize(&bus_config, &buffer_config, self.inner.as_ref());
+ }
+
kResultOk
}
@@ -894,6 +907,9 @@ impl<P: Plugin> IAudioProcessor for Wrapper<'_, P> {
.as_raw_vec()
.resize_with(bus_config.num_output_channels as usize, || &mut []);
+ // Also store this for later, so we can reinitialize the plugin after restoring state
+ self.inner.current_buffer_config.store(Some(buffer_config));
+
kResultOk
} else {
kResultFalse