Add boilerplate for Safety Limiter

plugins/safety_limiter/src/lib.rs

@@ -0,0 +1,110 @@
+// Safety limiter: ear protection for the 21st century
+// Copyright (C) 2022 Robbert van der Helm
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+use nih_plug::prelude::*;
+use std::sync::Arc;
+
+struct SafetyLimiter {
+    params: Arc<SafetyLimiterParams>,
+}
+
+#[derive(Params)]
+struct SafetyLimiterParams {
+    /// The level at which to start engaging the safety limiter. Stored as a gain ratio instead of
+    /// decibels.
+    #[id = "threshold"]
+    threshold_gain: FloatParam,
+}
+
+impl Default for SafetyLimiterParams {
+    fn default() -> Self {
+        Self {
+            threshold_gain: FloatParam::new(
+                "Threshold",
+                util::db_to_gain(0.00),
+                // This parameter mostly exists to allow small peaks through, so no need to go below
+                // 0 dBFS
+                FloatRange::Linear {
+                    min: util::db_to_gain(0.0),
+                    max: util::db_to_gain(12.0),
+                },
+            )
+            // And smoothing is not necessary here since we'll disable automation
+            .non_automatable()
+            .with_unit(" dB")
+            .with_value_to_string(formatters::v2s_f32_gain_to_db(2))
+            .with_string_to_value(formatters::s2v_f32_gain_to_db()),
+        }
+    }
+}
+
+impl Default for SafetyLimiter {
+    fn default() -> Self {
+        SafetyLimiter {
+            params: Arc::new(SafetyLimiterParams::default()),
+        }
+    }
+}
+
+impl Plugin for SafetyLimiter {
+    const NAME: &'static str = "Safety Limiter";
+    const VENDOR: &'static str = "Robbert van der Helm";
+    const URL: &'static str = "https://github.com/robbert-vdh/nih-plug";
+    const EMAIL: &'static str = "mail@robbertvanderhelm.nl";
+
+    const VERSION: &'static str = "0.1.0";
+
+    const DEFAULT_NUM_INPUTS: u32 = 2;
+    const DEFAULT_NUM_OUTPUTS: u32 = 2;
+
+    fn params(&self) -> Arc<dyn Params> {
+        self.params.clone()
+    }
+
+    fn accepts_bus_config(&self, config: &BusConfig) -> bool {
+        config.num_input_channels == config.num_output_channels
+    }
+
+    fn reset(&mut self) {
+        // TODO: Reset counters
+    }
+
+    fn process(
+        &mut self,
+        buffer: &mut Buffer,
+        _context: &mut impl ProcessContext,
+    ) -> ProcessStatus {
+        // TODO: Dew it
+
+        ProcessStatus::Normal
+    }
+}
+
+impl ClapPlugin for SafetyLimiter {
+    const CLAP_ID: &'static str = "nl.robbertvanderhelm.safety-limiter";
+    const CLAP_DESCRIPTION: &'static str = "Plays SOS in Morse code when redlining";
+    const CLAP_FEATURES: &'static [&'static str] = &["audio_effect", "stereo", "utility"];
+    const CLAP_MANUAL_URL: &'static str = Self::URL;
+    const CLAP_SUPPORT_URL: &'static str = Self::URL;
+}
+
+impl Vst3Plugin for SafetyLimiter {
+    const VST3_CLASS_ID: [u8; 16] = *b"SafetyLimtrRvdH.";
+    const VST3_CATEGORIES: &'static str = "Fx|Tools";
+}
+
+nih_export_clap!(SafetyLimiter);
+nih_export_vst3!(SafetyLimiter);