StereoPannerNode DOM (need to implement backend in servo/media)

components/script/dom/audionode.rs

@@ -236,6 +236,11 @@ impl AudioNodeMethods for AudioNode {
                     return Err(Error::NotSupported);
                 }
             },
+            EventTargetTypeId::AudioNode(AudioNodeTypeId::StereoPannerNode) => {
+                if value > 2 {
+                    return Err(Error::NotSupported);
+                }
+            },
             EventTargetTypeId::AudioNode(AudioNodeTypeId::ChannelMergerNode) => {
                 return Err(Error::InvalidState);
             },
@@ -280,6 +285,11 @@ impl AudioNodeMethods for AudioNode {
                     return Err(Error::NotSupported);
                 }
             },
+            EventTargetTypeId::AudioNode(AudioNodeTypeId::StereoPannerNode) => {
+                if value == ChannelCountMode::Max {
+                    return Err(Error::NotSupported);
+                }
+            },
             EventTargetTypeId::AudioNode(AudioNodeTypeId::ChannelMergerNode) => {
                 return Err(Error::InvalidState);
             },

components/script/dom/baseaudiocontext.rs

@@ -22,6 +22,7 @@ use crate::dom::bindings::codegen::Bindings::BaseAudioContextBinding::BaseAudioC
 use crate::dom::bindings::codegen::Bindings::BaseAudioContextBinding::DecodeErrorCallback;
 use crate::dom::bindings::codegen::Bindings::BaseAudioContextBinding::DecodeSuccessCallback;
 use crate::dom::bindings::codegen::Bindings::BiquadFilterNodeBinding::BiquadFilterOptions;
+use crate::dom::bindings::codegen::Bindings::StereoPannerNodeBinding::StereoPannerOptions;
 use crate::dom::bindings::codegen::Bindings::ChannelMergerNodeBinding::ChannelMergerOptions;
 use crate::dom::bindings::codegen::Bindings::ChannelSplitterNodeBinding::ChannelSplitterOptions;
 use crate::dom::bindings::codegen::Bindings::GainNodeBinding::GainOptions;
@@ -36,6 +37,7 @@ use crate::dom::bindings::root::{DomRoot, MutNullableDom};
 use crate::dom::biquadfilternode::BiquadFilterNode;
 use crate::dom::channelmergernode::ChannelMergerNode;
 use crate::dom::channelsplitternode::ChannelSplitterNode;
+use crate::dom::stereopannernode::StereoPannerNode;
 use crate::dom::domexception::{DOMErrorName, DOMException};
 use crate::dom::eventtarget::EventTarget;
 use crate::dom::gainnode::GainNode;
@@ -361,6 +363,16 @@ impl BaseAudioContextMethods for BaseAudioContext {
         )
     }
 
+
+    /// https://webaudio.github.io/web-audio-api/#dom-baseaudiocontext-createstereopanner
+    fn CreateStereoPanner(&self) -> Fallible<DomRoot<StereoPannerNode>> {
+        StereoPannerNode::new(
+            &self.global().as_window(),
+            &self,
+            &StereoPannerOptions::empty(),
+        )
+    }
+
     /// https://webaudio.github.io/web-audio-api/#dom-baseaudiocontext-createchannelmerger
     fn CreateChannelMerger(&self, count: u32) -> Fallible<DomRoot<ChannelMergerNode>> {
         let mut opts = ChannelMergerOptions::empty();

components/script/dom/mod.rs

@@ -457,6 +457,7 @@ pub mod serviceworkerglobalscope;
 pub mod serviceworkerregistration;
 pub mod servoparser;
 pub mod shadowroot;
+pub mod stereopannernode;
 pub mod storage;
 pub mod storageevent;
 pub mod stylepropertymapreadonly;

components/script/dom/stereopannernode.rs

@@ -0,0 +1,109 @@
+/* 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 https://mozilla.org/MPL/2.0/. */
+
+use crate::dom::audioparam::AudioParam;
+use crate::dom::audioscheduledsourcenode::AudioScheduledSourceNode;
+use crate::dom::baseaudiocontext::BaseAudioContext;
+use crate::dom::bindings::codegen::Bindings::AudioNodeBinding::{
+    ChannelCountMode, ChannelInterpretation,
+};
+use crate::dom::bindings::codegen::Bindings::AudioParamBinding::AutomationRate;
+use crate::dom::bindings::codegen::Bindings::StereoPannerNodeBinding::StereoPannerNodeMethods;
+use crate::dom::bindings::codegen::Bindings::StereoPannerNodeBinding::{
+    self, StereoPannerOptions,
+};
+use crate::dom::bindings::error::Fallible;
+use crate::dom::bindings::reflector::reflect_dom_object;
+use crate::dom::bindings::root::{Dom, DomRoot};
+use crate::dom::window::Window;
+use dom_struct::dom_struct;
+use servo_media::audio::stereo_panner_node::StereoPannerOptions as ServoMediaStereoPannerOptions;
+use servo_media::audio::node::AudioNodeInit;
+use servo_media::audio::param::ParamType;
+use std::f32;
+
+#[dom_struct]
+pub struct StereoPannerNode {
+    source_node: AudioScheduledSourceNode,
+    offset: Dom<AudioParam>,
+}
+
+impl StereoPannerNode {
+    #[allow(unrooted_must_root)]
+    pub fn new_inherited(
+        window: &Window,
+        context: &BaseAudioContext,
+        options: &StereoPannerOptions,
+    ) -> Fallible<StereoPannerNode> {
+        let node_options =
+            options
+                .parent
+                .unwrap_or(2, ChannelCountMode::ClampedMax, ChannelInterpretation::Speakers);
+        if node_options.mode == ChannelCountMode::Max {
+            return Err(Error::NotSupported);
+        }
+        if node_options.count > 2 || node_options.count == 0 {
+            return Err(Error::NotSupported);
+        }
+        let source_node = AudioScheduledSourceNode::new_inherited(
+            AudioNodeInit::StereoPannerNode(options.into()),
+            context,
+            node_options,
+            0, /* inputs */
+            1, /* outputs */
+        )?;
+        let node_id = source_node.node().node_id();
+        let offset = AudioParam::new(
+            window,
+            context,
+            node_id,
+            ParamType::Offset,
+            AutomationRate::A_rate,
+            1.,
+            f32::MIN,
+            f32::MAX,
+        );
+
+        Ok(StereoPannerNode {
+            source_node,
+            offset: Dom::from_ref(&offset),
+        })
+    }
+
+    #[allow(unrooted_must_root)]
+    pub fn new(
+        window: &Window,
+        context: &BaseAudioContext,
+        options: &StereoPannerOptions,
+    ) -> Fallible<DomRoot<StereoPannerNode>> {
+        let node = StereoPannerNode::new_inherited(window, context, options)?;
+        Ok(reflect_dom_object(
+            Box::new(node),
+            window,
+            StereoPannerNodeBinding::Wrap,
+        ))
+    }
+
+    pub fn Constructor(
+        window: &Window,
+        context: &BaseAudioContext,
+        options: &StereoPannerOptions,
+    ) -> Fallible<DomRoot<StereoPannerNode>> {
+        StereoPannerNode::new(window, context, options)
+    }
+}
+
+impl StereoPannerNodeMethods for StereoPannerNode {
+    fn Offset(&self) -> DomRoot<AudioParam> {
+        DomRoot::from_ref(&self.offset)
+    }
+}
+
+impl<'a> From<&'a StereoPannerOptions> for ServoMediaStereoPannerOptions {
+    fn from(options: &'a StereoPannerOptions) -> Self {
+        Self {
+            offset: *options.offset,
+        }
+    }
+}

components/script/dom/webidls/BaseAudioContext.webidl

@@ -43,7 +43,7 @@ interface BaseAudioContext : EventTarget {
   //                               sequence<double> feedback);
   // WaveShaperNode createWaveShaper();
   [Throws] PannerNode createPanner();
-  // StereoPannerNode createStereoPanner();
+  [Throws] StereoPannerNode createStereoPanner();
   // ConvolverNode createConvolver();
   [Throws] ChannelSplitterNode createChannelSplitter(optional unsigned long numberOfOutputs = 6);
   [Throws] ChannelMergerNode createChannelMerger(optional unsigned long numberOfInputs = 6);

components/script/dom/webidls/StereoPannerNode.webidl

@@ -0,0 +1,17 @@
+/* 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 https://mozilla.org/MPL/2.0/. */
+/*
+ * The origin of this IDL file is
+ * https://webaudio.github.io/web-audio-api/#StereoPannerNode
+ */
+
+dictionary StereoPannerOptions: AudioNodeOptions {
+  float pan = 0;
+};
+
+[Exposed=Window,
+ Constructor (BaseAudioContext context, optional StereoPannerOptions options)]
+interface StereoPannerNode : AudioScheduledSourceNode {
+  readonly attribute AudioParam offset;
+};