Auto merge of #21750 - Manishearth:biquad, r=ferjm

Implement BiquadFilterNode

A bunch of tests still fail but some of it may be a timing issue, looking at it the tests are *at least* affected by https://github.com/servo/servo/issues/21659 (changing how they work to avoid problems from that does not make them pass but does change the exact value of the error), so I feel like I should fix that first before investigating these.

r? @ferjm

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6 files changed, 233 insertions, 2 deletions

diff --git a/components/script/dom/baseaudiocontext.rs b/components/script/dom/baseaudiocontext.rs
index f539f81bc4e..b892049a8ec 100644
--- a/components/script/dom/baseaudiocontext.rs
+++ b/components/script/dom/baseaudiocontext.rs
@@ -18,6 +18,7 @@ use dom::bindings::codegen::Bindings::BaseAudioContextBinding::AudioContextState
 use dom::bindings::codegen::Bindings::BaseAudioContextBinding::BaseAudioContextMethods;
 use dom::bindings::codegen::Bindings::BaseAudioContextBinding::DecodeErrorCallback;
 use dom::bindings::codegen::Bindings::BaseAudioContextBinding::DecodeSuccessCallback;
+use dom::bindings::codegen::Bindings::BiquadFilterNodeBinding::BiquadFilterOptions;
 use dom::bindings::codegen::Bindings::ChannelMergerNodeBinding::ChannelMergerOptions;
 use dom::bindings::codegen::Bindings::GainNodeBinding::GainOptions;
 use dom::bindings::codegen::Bindings::OscillatorNodeBinding::OscillatorOptions;
@@ -28,6 +29,7 @@ use dom::bindings::num::Finite;
 use dom::bindings::refcounted::Trusted;
 use dom::bindings::reflector::DomObject;
 use dom::bindings::root::{DomRoot, MutNullableDom};
+use dom::biquadfilternode::BiquadFilterNode;
 use dom::channelmergernode::ChannelMergerNode;
 use dom::domexception::{DOMErrorName, DOMException};
 use dom::eventtarget::EventTarget;
@@ -344,6 +346,11 @@ impl BaseAudioContextMethods for BaseAudioContext {
         AnalyserNode::new(&self.global().as_window(), &self, &AnalyserOptions::empty())
     }
 
+    /// https://webaudio.github.io/web-audio-api/#dom-baseaudiocontext-createbiquadfilter
+    fn CreateBiquadFilter(&self) -> Fallible<DomRoot<BiquadFilterNode>> {
+        BiquadFilterNode::new(&self.global().as_window(), &self, &BiquadFilterOptions::empty())
+    }
+
     /// https://webaudio.github.io/web-audio-api/#dom-baseaudiocontext-createchannelmerger
     fn CreateChannelMerger(&self, count: u32) -> Fallible<DomRoot<ChannelMergerNode>> {
         let mut opts = ChannelMergerOptions::empty();
diff --git a/components/script/dom/biquadfilternode.rs b/components/script/dom/biquadfilternode.rs
new file mode 100644
index 00000000000..2ee309498be
--- /dev/null
+++ b/components/script/dom/biquadfilternode.rs
@@ -0,0 +1,184 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+use dom::audionode::AudioNode;
+use dom::audioparam::AudioParam;
+use dom::baseaudiocontext::BaseAudioContext;
+use dom::bindings::codegen::Bindings::AudioNodeBinding::{ChannelCountMode, ChannelInterpretation};
+use dom::bindings::codegen::Bindings::AudioParamBinding::AutomationRate;
+use dom::bindings::codegen::Bindings::BiquadFilterNodeBinding::{self, BiquadFilterNodeMethods};
+use dom::bindings::codegen::Bindings::BiquadFilterNodeBinding::BiquadFilterOptions;
+use dom::bindings::codegen::Bindings::BiquadFilterNodeBinding::BiquadFilterType;
+use dom::bindings::error::Fallible;
+use dom::bindings::reflector::reflect_dom_object;
+use dom::bindings::root::{Dom, DomRoot};
+use dom::window::Window;
+use dom_struct::dom_struct;
+use servo_media::audio::biquad_filter_node::{BiquadFilterNodeOptions, FilterType};
+use servo_media::audio::biquad_filter_node::BiquadFilterNodeMessage;
+use servo_media::audio::node::{AudioNodeInit, AudioNodeMessage};
+use servo_media::audio::param::ParamType;
+use std::cell::Cell;
+use std::f32;
+
+#[dom_struct]
+pub struct BiquadFilterNode {
+    node: AudioNode,
+    gain: Dom<AudioParam>,
+    frequency: Dom<AudioParam>,
+    q: Dom<AudioParam>,
+    detune: Dom<AudioParam>,
+    filter: Cell<BiquadFilterType>,
+}
+
+impl BiquadFilterNode {
+    #[allow(unrooted_must_root)]
+    pub fn new_inherited(
+        window: &Window,
+        context: &BaseAudioContext,
+        options: &BiquadFilterOptions,
+    ) -> Fallible<BiquadFilterNode> {
+        let node_options = options.parent
+                                  .unwrap_or(2, ChannelCountMode::Max,
+                                             ChannelInterpretation::Speakers);
+        let filter = Cell::new(options.type_);
+        let options = options.into();
+        let node = AudioNode::new_inherited(
+            AudioNodeInit::BiquadFilterNode(options),
+            context,
+            node_options,
+            1, // inputs
+            1, // outputs
+        )?;
+        let gain = AudioParam::new(
+            window,
+            context,
+            node.node_id(),
+            ParamType::Gain,
+            AutomationRate::A_rate,
+            options.gain,       // default value
+            f32::MIN, // min value
+            f32::MAX, // max value
+        );
+        let q = AudioParam::new(
+            window,
+            context,
+            node.node_id(),
+            ParamType::Q,
+            AutomationRate::A_rate,
+            options.q,       // default value
+            f32::MIN, // min value
+            f32::MAX, // max value
+        );
+        let frequency = AudioParam::new(
+            window,
+            context,
+            node.node_id(),
+            ParamType::Frequency,
+            AutomationRate::A_rate,
+            options.frequency,       // default value
+            f32::MIN, // min value
+            f32::MAX, // max value
+        );
+        let detune = AudioParam::new(
+            window,
+            context,
+            node.node_id(),
+            ParamType::Detune,
+            AutomationRate::A_rate,
+            options.detune,       // default value
+            f32::MIN, // min value
+            f32::MAX, // max value
+        );
+        Ok(BiquadFilterNode {
+            node,
+            filter,
+            gain: Dom::from_ref(&gain),
+            q: Dom::from_ref(&q),
+            frequency: Dom::from_ref(&frequency),
+            detune: Dom::from_ref(&detune),
+        })
+    }
+
+    #[allow(unrooted_must_root)]
+    pub fn new(
+        window: &Window,
+        context: &BaseAudioContext,
+        options: &BiquadFilterOptions,
+    ) -> Fallible<DomRoot<BiquadFilterNode>> {
+        let node = BiquadFilterNode::new_inherited(window, context, options)?;
+        Ok(reflect_dom_object(Box::new(node), window, BiquadFilterNodeBinding::Wrap))
+    }
+
+    pub fn Constructor(
+        window: &Window,
+        context: &BaseAudioContext,
+        options: &BiquadFilterOptions,
+    ) -> Fallible<DomRoot<BiquadFilterNode>> {
+        BiquadFilterNode::new(window, context, options)
+    }
+}
+
+impl BiquadFilterNodeMethods for BiquadFilterNode {
+    // https://webaudio.github.io/web-audio-api/#dom-biquadfilternode-gain
+    fn Gain(&self) -> DomRoot<AudioParam> {
+        DomRoot::from_ref(&self.gain)
+    }
+
+    // https://webaudio.github.io/web-audio-api/#dom-biquadfilternode-q
+    fn Q(&self) -> DomRoot<AudioParam> {
+        DomRoot::from_ref(&self.q)
+    }
+
+    // https://webaudio.github.io/web-audio-api/#dom-biquadfilternode-detune
+    fn Detune(&self) -> DomRoot<AudioParam> {
+        DomRoot::from_ref(&self.detune)
+    }
+
+    // https://webaudio.github.io/web-audio-api/#dom-biquadfilternode-frequency
+    fn Frequency(&self) -> DomRoot<AudioParam> {
+        DomRoot::from_ref(&self.frequency)
+    }
+
+    // https://webaudio.github.io/web-audio-api/#dom-biquadfilternode-type
+    fn Type(&self) -> BiquadFilterType {
+        self.filter.get()
+    }
+
+    // https://webaudio.github.io/web-audio-api/#dom-biquadfilternode-type
+    fn SetType(&self, filter: BiquadFilterType) {
+        self.filter.set(filter);
+        self.node
+            .message(AudioNodeMessage::BiquadFilterNode(
+                BiquadFilterNodeMessage::SetFilterType(filter.into()),
+            ));
+    }
+}
+
+impl<'a> From<&'a BiquadFilterOptions> for BiquadFilterNodeOptions {
+    fn from(options: &'a BiquadFilterOptions) -> Self {
+        Self {
+            gain: *options.gain,
+            q: *options.Q,
+            frequency: *options.frequency,
+            detune: *options.detune,
+            filter: options.type_.into()
+        }
+    }
+}
+
+impl From<BiquadFilterType> for FilterType {
+    fn from(filter: BiquadFilterType) -> FilterType {
+        match filter {
+            BiquadFilterType::Lowpass => FilterType::LowPass,
+            BiquadFilterType::Highpass => FilterType::HighPass,
+            BiquadFilterType::Bandpass => FilterType::BandPass,
+            BiquadFilterType::Lowshelf => FilterType::LowShelf,
+            BiquadFilterType::Highshelf => FilterType::HighShelf,
+            BiquadFilterType::Peaking => FilterType::Peaking,
+            BiquadFilterType::Allpass => FilterType::AllPass,
+            BiquadFilterType::Notch => FilterType::Notch,
+        }
+    }
+}
diff --git a/components/script/dom/gainnode.rs b/components/script/dom/gainnode.rs
index ea81ac58535..7e2235f5e80 100644
--- a/components/script/dom/gainnode.rs
+++ b/components/script/dom/gainnode.rs
@@ -48,7 +48,7 @@ impl GainNode {
             node.node_id(),
             ParamType::Gain,
             AutomationRate::A_rate,
-            1.,       // default value
+            *options.gain,  // default value
             f32::MIN, // min value
             f32::MAX, // max value
         );
diff --git a/components/script/dom/mod.rs b/components/script/dom/mod.rs
index 54b9adcc422..07425cccae1 100644
--- a/components/script/dom/mod.rs
+++ b/components/script/dom/mod.rs
@@ -228,6 +228,7 @@ pub mod audioscheduledsourcenode;
 pub mod baseaudiocontext;
 pub mod beforeunloadevent;
 pub mod bindings;
+pub mod biquadfilternode;
 pub mod blob;
 pub mod bluetooth;
 pub mod bluetoothadvertisingevent;
diff --git a/components/script/dom/webidls/BaseAudioContext.webidl b/components/script/dom/webidls/BaseAudioContext.webidl
index 9b8d8c5efa1..2883e60ffd8 100644
--- a/components/script/dom/webidls/BaseAudioContext.webidl
+++ b/components/script/dom/webidls/BaseAudioContext.webidl
@@ -38,7 +38,7 @@ interface BaseAudioContext : EventTarget {
   [Throws] AnalyserNode createAnalyser();
   [Throws]  GainNode createGain();
   // DelayNode createDelay(optional double maxDelayTime = 1);
-  // BiquadFilterNode createBiquadFilter();
+  [Throws] BiquadFilterNode createBiquadFilter();
   // IIRFilterNode createIIRFilter(sequence<double> feedforward,
   //                               sequence<double> feedback);
   // WaveShaperNode createWaveShaper();
diff --git a/components/script/dom/webidls/BiquadFilterNode.webidl b/components/script/dom/webidls/BiquadFilterNode.webidl
new file mode 100644
index 00000000000..24e993f5aa4
--- /dev/null
+++ b/components/script/dom/webidls/BiquadFilterNode.webidl
@@ -0,0 +1,39 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+/*
+ * The origin of this IDL file is
+ * https://webaudio.github.io/web-audio-api/#biquadfilternode
+ */
+
+enum BiquadFilterType {
+  "lowpass",
+  "highpass",
+  "bandpass",
+  "lowshelf",
+  "highshelf",
+  "peaking",
+  "notch",
+  "allpass"
+};
+
+dictionary BiquadFilterOptions : AudioNodeOptions {
+  BiquadFilterType type = "lowpass";
+  float Q = 1;
+  float detune = 0;
+  float frequency = 350;
+  float gain = 0;
+};
+
+[Exposed=Window,
+ Constructor (BaseAudioContext context, optional BiquadFilterOptions options)]
+interface BiquadFilterNode : AudioNode {
+  attribute BiquadFilterType type;
+  readonly attribute AudioParam frequency;
+  readonly attribute AudioParam detune;
+  readonly attribute AudioParam Q;
+  readonly attribute AudioParam gain;
+  // the AudioParam model of https://github.com/servo/servo/issues/21659 needs to
+  // be implemented before we implement this
+  // void getFrequencyResponse (Float32Array frequencyHz, Float32Array magResponse, Float32Array phaseResponse);
+};