lib/web_ui/lib/src/engine/configuration.dart - mirrors/engine - Git at Google

 // Copyright 2013 The Flutter Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

 /// JavaScript API a Flutter Web application can use to configure the Web
 /// Engine.
 ///
 /// The configuration is a plain JavaScript object set as the
 /// `flutterConfiguration` property of the top-level `window` object.
 ///
 /// Example:
 ///
 ///     <head>
 ///       <script>
 ///         window.flutterConfiguration = {
 ///           canvasKitBaseUrl: "https://example.com/my-custom-canvaskit/"
 ///         };
 ///       </script>
 ///     </head>
 ///
 /// Configuration properties supplied via `window.flutterConfiguration`
 /// override those supplied using the corresponding environment variables. For
 /// example, if both `window.flutterConfiguration.canvasKitBaseUrl` and the
 /// `FLUTTER_WEB_CANVASKIT_URL` environment variables are provided,
 /// `window.flutterConfiguration.canvasKitBaseUrl` is used.

 @JS()
 library configuration;

 import 'package:js/js.dart';

 /// The version of CanvasKit used by the web engine by default.
 // DO NOT EDIT THE NEXT LINE OF CODE MANUALLY
 // See `lib/web_ui/README.md` for how to roll CanvasKit to a new version.
 const String _canvaskitVersion = '0.35.0';

 /// The Web Engine configuration for the current application.
 FlutterConfiguration get configuration => _configuration ??= FlutterConfiguration(_jsConfiguration);
 FlutterConfiguration? _configuration;

 /// Sets the given configuration as the current one.
 ///
 /// This must be called before the engine is initialized. Calling it after the
 /// engine is initialized will result in some of the properties not taking
 /// effect because they are consumed during initialization.
 void debugSetConfiguration(FlutterConfiguration configuration) {
   _configuration = configuration;
 }

 /// Supplies Web Engine configuration properties.
 class FlutterConfiguration {
   /// Constructs a configuration from a JavaScript object containing
   /// runtime-supplied properties.
   FlutterConfiguration(this._js);

   final JsFlutterConfiguration? _js;

   // Static constant parameters.
   //
   // These properties affect tree shaking and therefore cannot be supplied at
   // runtime. They must be static constants for the compiler to remove dead
   // effectively.

   /// Auto detect which rendering backend to use.
   ///
   /// Using flutter tools option "--web-render=auto" or not specifying one
   /// would set the value to true. Otherwise, it would be false.
   static const bool flutterWebAutoDetect =
       bool.fromEnvironment('FLUTTER_WEB_AUTO_DETECT', defaultValue: true);

   static const bool flutterWebUseSkwasm =
       bool.fromEnvironment('FLUTTER_WEB_USE_SKWASM');

   /// Enable the Skia-based rendering backend.
   ///
   /// Using flutter tools option "--web-render=canvaskit" would set the value to
   /// true.
   ///
   /// Using flutter tools option "--web-render=html" would set the value to false.
   static const bool useSkia =
       bool.fromEnvironment('FLUTTER_WEB_USE_SKIA');


   // Runtime parameters.
   //
   // These parameters can be supplied either as environment variables, or at
   // runtime. Runtime-supplied values take precedence over environment
   // variables.

   /// The URL to use when downloading the CanvasKit script and associated wasm.
   ///
   /// The expected directory structure nested under this URL is as follows:
   ///
   ///     /canvaskit.js              - the release build of CanvasKit JS API bindings
   ///     /canvaskit.wasm            - the release build of CanvasKit WASM module
   ///     /profiling/canvaskit.js    - the profile build of CanvasKit JS API bindings
   ///     /profiling/canvaskit.wasm  - the profile build of CanvasKit WASM module
   ///
   /// The base URL can be overridden using the `FLUTTER_WEB_CANVASKIT_URL`
   /// environment variable or using the configuration API for JavaScript.
   ///
   /// When specifying using the environment variable set it in the Flutter tool
   /// using the `--dart-define` option. The value must end with a `/`.
   ///
   /// Example:
   ///
   /// ```
   /// flutter run \
   ///   -d chrome \
   ///   --web-renderer=canvaskit \
   ///   --dart-define=FLUTTER_WEB_CANVASKIT_URL=https://example.com/custom-canvaskit-build/
   /// ```
   String get canvasKitBaseUrl => _js?.canvasKitBaseUrl ?? _defaultCanvasKitBaseUrl;
   static const String _defaultCanvasKitBaseUrl = String.fromEnvironment(
     'FLUTTER_WEB_CANVASKIT_URL',
     defaultValue: 'https://unpkg.com/canvaskit-wasm@$_canvaskitVersion/bin/',
   );

   /// If set to true, forces CPU-only rendering in CanvasKit (i.e. the engine
   /// won't use WebGL).
   ///
   /// This is mainly used for testing or for apps that want to ensure they
   /// run on devices which don't support WebGL.
   bool get canvasKitForceCpuOnly => _js?.canvasKitForceCpuOnly ?? _defaultCanvasKitForceCpuOnly;
   static const bool _defaultCanvasKitForceCpuOnly = bool.fromEnvironment(
     'FLUTTER_WEB_CANVASKIT_FORCE_CPU_ONLY',
   );

   /// The maximum number of overlay surfaces that the CanvasKit renderer will use.
   ///
   /// Overlay surfaces are extra WebGL `<canvas>` elements used to paint on top
   /// of platform views. Too many platform views can cause the browser to run
   /// out of resources (memory, CPU, GPU) to handle the content efficiently.
   /// The number of overlay surfaces is therefore limited.
   ///
   /// This value can be specified using either the `FLUTTER_WEB_MAXIMUM_SURFACES`
   /// environment variable, or using the runtime configuration.
   int get canvasKitMaximumSurfaces => _js?.canvasKitMaximumSurfaces ?? _defaultCanvasKitMaximumSurfaces;
   static const int _defaultCanvasKitMaximumSurfaces = int.fromEnvironment(
     'FLUTTER_WEB_MAXIMUM_SURFACES',
     defaultValue: 8,
   );

   /// Set this flag to `true` to cause the engine to visualize the semantics tree
   /// on the screen for debugging.
   ///
   /// This only works in profile and release modes. Debug mode does not support
   /// passing compile-time constants.
   ///
   /// Example:
   ///
   /// ```
   /// flutter run -d chrome --profile --dart-define=FLUTTER_WEB_DEBUG_SHOW_SEMANTICS=true
   /// ```
   bool get debugShowSemanticsNodes => _js?.debugShowSemanticsNodes ?? _defaultDebugShowSemanticsNodes;
   static const bool _defaultDebugShowSemanticsNodes = bool.fromEnvironment(
     'FLUTTER_WEB_DEBUG_SHOW_SEMANTICS',
   );
 }

 @JS('window.flutterConfiguration')
 external JsFlutterConfiguration? get _jsConfiguration;

 /// The JS bindings for the object that's set as `window.flutterConfiguration`.
 @JS()
 @staticInterop
 class JsFlutterConfiguration {}

 extension JsFlutterConfigurationExtension on JsFlutterConfiguration {
   external String? get canvasKitBaseUrl;
   external bool? get canvasKitForceCpuOnly;
   external bool? get debugShowSemanticsNodes;

   external int? get canvasKitMaximumSurfaces;
   external set canvasKitMaximumSurfaces(int? maxSurfaces);
 }

 /// A JavaScript entrypoint that allows developer to set rendering backend
 /// at runtime before launching the application.
 @JS('window.flutterWebRenderer')
 external String? get requestedRendererType;
	// Copyright 2013 The Flutter Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.

	/// JavaScript API a Flutter Web application can use to configure the Web
	/// Engine.
	///
	/// The configuration is a plain JavaScript object set as the
	/// `flutterConfiguration` property of the top-level `window` object.
	///
	/// Example:
	///
	/// <head>
	/// <script>
	/// window.flutterConfiguration = {
	/// canvasKitBaseUrl: "https://example.com/my-custom-canvaskit/"
	/// };
	/// </script>
	/// </head>
	///
	/// Configuration properties supplied via `window.flutterConfiguration`
	/// override those supplied using the corresponding environment variables. For
	/// example, if both `window.flutterConfiguration.canvasKitBaseUrl` and the
	/// `FLUTTER_WEB_CANVASKIT_URL` environment variables are provided,
	/// `window.flutterConfiguration.canvasKitBaseUrl` is used.

	@JS()
	library configuration;

	import 'package:js/js.dart';

	/// The version of CanvasKit used by the web engine by default.
	// DO NOT EDIT THE NEXT LINE OF CODE MANUALLY
	// See `lib/web_ui/README.md` for how to roll CanvasKit to a new version.
	const String _canvaskitVersion = '0.35.0';

	/// The Web Engine configuration for the current application.
	FlutterConfiguration get configuration => _configuration ??= FlutterConfiguration(_jsConfiguration);
	FlutterConfiguration? _configuration;

	/// Sets the given configuration as the current one.
	///
	/// This must be called before the engine is initialized. Calling it after the
	/// engine is initialized will result in some of the properties not taking
	/// effect because they are consumed during initialization.
	void debugSetConfiguration(FlutterConfiguration configuration) {
	_configuration = configuration;
	}

	/// Supplies Web Engine configuration properties.
	class FlutterConfiguration {
	/// Constructs a configuration from a JavaScript object containing
	/// runtime-supplied properties.
	FlutterConfiguration(this._js);

	final JsFlutterConfiguration? _js;

	// Static constant parameters.
	//
	// These properties affect tree shaking and therefore cannot be supplied at
	// runtime. They must be static constants for the compiler to remove dead
	// effectively.

	/// Auto detect which rendering backend to use.
	///
	/// Using flutter tools option "--web-render=auto" or not specifying one
	/// would set the value to true. Otherwise, it would be false.
	static const bool flutterWebAutoDetect =
	bool.fromEnvironment('FLUTTER_WEB_AUTO_DETECT', defaultValue: true);

	static const bool flutterWebUseSkwasm =
	bool.fromEnvironment('FLUTTER_WEB_USE_SKWASM');

	/// Enable the Skia-based rendering backend.
	///
	/// Using flutter tools option "--web-render=canvaskit" would set the value to
	/// true.
	///
	/// Using flutter tools option "--web-render=html" would set the value to false.
	static const bool useSkia =
	bool.fromEnvironment('FLUTTER_WEB_USE_SKIA');


	// Runtime parameters.
	//
	// These parameters can be supplied either as environment variables, or at
	// runtime. Runtime-supplied values take precedence over environment
	// variables.

	/// The URL to use when downloading the CanvasKit script and associated wasm.
	///
	/// The expected directory structure nested under this URL is as follows:
	///
	/// /canvaskit.js - the release build of CanvasKit JS API bindings
	/// /canvaskit.wasm - the release build of CanvasKit WASM module
	/// /profiling/canvaskit.js - the profile build of CanvasKit JS API bindings
	/// /profiling/canvaskit.wasm - the profile build of CanvasKit WASM module
	///
	/// The base URL can be overridden using the `FLUTTER_WEB_CANVASKIT_URL`
	/// environment variable or using the configuration API for JavaScript.
	///
	/// When specifying using the environment variable set it in the Flutter tool
	/// using the `--dart-define` option. The value must end with a `/`.
	///
	/// Example:
	///
	/// ```
	/// flutter run \
	/// -d chrome \
	/// --web-renderer=canvaskit \
	/// --dart-define=FLUTTER_WEB_CANVASKIT_URL=https://example.com/custom-canvaskit-build/
	/// ```
	String get canvasKitBaseUrl => _js?.canvasKitBaseUrl ?? _defaultCanvasKitBaseUrl;
	static const String _defaultCanvasKitBaseUrl = String.fromEnvironment(
	'FLUTTER_WEB_CANVASKIT_URL',
	defaultValue: 'https://unpkg.com/canvaskit-wasm@$_canvaskitVersion/bin/',
	);

	/// If set to true, forces CPU-only rendering in CanvasKit (i.e. the engine
	/// won't use WebGL).
	///
	/// This is mainly used for testing or for apps that want to ensure they
	/// run on devices which don't support WebGL.
	bool get canvasKitForceCpuOnly => _js?.canvasKitForceCpuOnly ?? _defaultCanvasKitForceCpuOnly;
	static const bool _defaultCanvasKitForceCpuOnly = bool.fromEnvironment(
	'FLUTTER_WEB_CANVASKIT_FORCE_CPU_ONLY',
	);

	/// The maximum number of overlay surfaces that the CanvasKit renderer will use.
	///
	/// Overlay surfaces are extra WebGL `<canvas>` elements used to paint on top
	/// of platform views. Too many platform views can cause the browser to run
	/// out of resources (memory, CPU, GPU) to handle the content efficiently.
	/// The number of overlay surfaces is therefore limited.
	///
	/// This value can be specified using either the `FLUTTER_WEB_MAXIMUM_SURFACES`
	/// environment variable, or using the runtime configuration.
	int get canvasKitMaximumSurfaces => _js?.canvasKitMaximumSurfaces ?? _defaultCanvasKitMaximumSurfaces;
	static const int _defaultCanvasKitMaximumSurfaces = int.fromEnvironment(
	'FLUTTER_WEB_MAXIMUM_SURFACES',
	defaultValue: 8,
	);

	/// Set this flag to `true` to cause the engine to visualize the semantics tree
	/// on the screen for debugging.
	///
	/// This only works in profile and release modes. Debug mode does not support
	/// passing compile-time constants.
	///
	/// Example:
	///
	/// ```
	/// flutter run -d chrome --profile --dart-define=FLUTTER_WEB_DEBUG_SHOW_SEMANTICS=true
	/// ```
	bool get debugShowSemanticsNodes => _js?.debugShowSemanticsNodes ?? _defaultDebugShowSemanticsNodes;
	static const bool _defaultDebugShowSemanticsNodes = bool.fromEnvironment(
	'FLUTTER_WEB_DEBUG_SHOW_SEMANTICS',
	);
	}

	@JS('window.flutterConfiguration')
	external JsFlutterConfiguration? get _jsConfiguration;

	/// The JS bindings for the object that's set as `window.flutterConfiguration`.
	@JS()
	@staticInterop
	class JsFlutterConfiguration {}

	extension JsFlutterConfigurationExtension on JsFlutterConfiguration {
	external String? get canvasKitBaseUrl;
	external bool? get canvasKitForceCpuOnly;
	external bool? get debugShowSemanticsNodes;

	external int? get canvasKitMaximumSurfaces;
	external set canvasKitMaximumSurfaces(int? maxSurfaces);
	}

	/// A JavaScript entrypoint that allows developer to set rendering backend
	/// at runtime before launching the application.
	@JS('window.flutterWebRenderer')
	external String? get requestedRendererType;