LibWeb: Add barebones CanvasGradient object

Also add the CanvasRenderingContext2D APIs to go along with it.
Note that it can't be used for anything yet.

Meta/Lagom/Tools/CodeGenerators/LibWeb/WrapperGenerator.cpp

@@ -3451,6 +3451,7 @@ void generate_prototype_implementation(IDL::Interface const& interface)
 #include <LibWeb/Bindings/CSSRuleWrapperFactory.h>
 #include <LibWeb/Bindings/CSSStyleDeclarationWrapper.h>
 #include <LibWeb/Bindings/CSSStyleSheetWrapper.h>
+#include <LibWeb/Bindings/CanvasGradientWrapper.h>
 #include <LibWeb/Bindings/CanvasRenderingContext2DWrapper.h>
 #include <LibWeb/Bindings/CommentWrapper.h>
 #include <LibWeb/Bindings/DOMImplementationWrapper.h>

Userland/Libraries/LibWeb/Bindings/WindowObjectHelper.h

@@ -22,6 +22,8 @@
 #include <LibWeb/Bindings/CSSStyleRulePrototype.h>
 #include <LibWeb/Bindings/CSSStyleSheetConstructor.h>
 #include <LibWeb/Bindings/CSSStyleSheetPrototype.h>
+#include <LibWeb/Bindings/CanvasGradientConstructor.h>
+#include <LibWeb/Bindings/CanvasGradientPrototype.h>
 #include <LibWeb/Bindings/CanvasRenderingContext2DConstructor.h>
 #include <LibWeb/Bindings/CanvasRenderingContext2DPrototype.h>
 #include <LibWeb/Bindings/CharacterDataConstructor.h>
@@ -303,6 +305,7 @@
     ADD_WINDOW_OBJECT_INTERFACE(CSSStyleDeclaration)       \
     ADD_WINDOW_OBJECT_INTERFACE(CSSStyleRule)              \
     ADD_WINDOW_OBJECT_INTERFACE(CSSStyleSheet)             \
+    ADD_WINDOW_OBJECT_INTERFACE(CanvasGradient)            \
     ADD_WINDOW_OBJECT_INTERFACE(CanvasRenderingContext2D)  \
     ADD_WINDOW_OBJECT_INTERFACE(CharacterData)             \
     ADD_WINDOW_OBJECT_INTERFACE(CloseEvent)                \

Userland/Libraries/LibWeb/CMakeLists.txt

@@ -99,6 +99,7 @@ set(SOURCES
     HTML/AttributeNames.cpp
     HTML/BrowsingContext.cpp
     HTML/BrowsingContextContainer.cpp
+    HTML/CanvasGradient.cpp
     HTML/CanvasRenderingContext2D.cpp
     HTML/DOMParser.cpp
     HTML/DOMStringMap.cpp
@@ -406,6 +407,7 @@ libweb_js_wrapper(DOM/Text)
 libweb_js_wrapper(Encoding/TextEncoder)
 libweb_js_wrapper(Geometry/DOMRect)
 libweb_js_wrapper(Geometry/DOMRectReadOnly)
+libweb_js_wrapper(HTML/CanvasGradient)
 libweb_js_wrapper(HTML/CanvasRenderingContext2D)
 libweb_js_wrapper(HTML/CloseEvent)
 libweb_js_wrapper(HTML/DOMParser)

Userland/Libraries/LibWeb/Forward.h

@@ -307,6 +307,7 @@ namespace Web::Bindings {
 class AbortControllerWrapper;
 class AbortSignalWrapper;
 class AttributeWrapper;
+class CanvasGradientWrapper;
 class CanvasRenderingContext2DWrapper;
 class CharacterDataWrapper;
 class CloseEventWrapper;

Userland/Libraries/LibWeb/HTML/CanvasGradient.cpp

@@ -0,0 +1,53 @@
+/*
+ * Copyright (c) 2022, Andreas Kling <kling@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibWeb/HTML/CanvasGradient.h>
+
+namespace Web::HTML {
+
+NonnullRefPtr<CanvasGradient> CanvasGradient::create_radial(double x0, double y0, double r0, double x1, double y1, double r1)
+{
+    (void)x0;
+    (void)y0;
+    (void)r0;
+    (void)x1;
+    (void)y1;
+    (void)r1;
+    return adopt_ref(*new CanvasGradient(Type::Radial));
+}
+
+NonnullRefPtr<CanvasGradient> CanvasGradient::create_linear(double x0, double y0, double x1, double y1)
+{
+    (void)x0;
+    (void)y0;
+    (void)x1;
+    (void)y1;
+    return adopt_ref(*new CanvasGradient(Type::Linear));
+}
+
+NonnullRefPtr<CanvasGradient> CanvasGradient::create_conic(double start_angle, double x, double y)
+{
+    (void)start_angle;
+    (void)x;
+    (void)y;
+    return adopt_ref(*new CanvasGradient(Type::Conic));
+}
+
+CanvasGradient::CanvasGradient(Type type)
+    : m_type(type)
+{
+}
+
+CanvasGradient::~CanvasGradient()
+{
+}
+
+void CanvasGradient::add_color_stop(double offset, String const& color)
+{
+    dbgln("CanvasGradient#addColorStop({}, '{}')", offset, color);
+}
+
+}

Userland/Libraries/LibWeb/HTML/CanvasGradient.h

@@ -0,0 +1,40 @@
+/*
+ * Copyright (c) 2022, Andreas Kling <kling@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/RefCounted.h>
+#include <LibWeb/Bindings/Wrappable.h>
+
+namespace Web::HTML {
+
+class CanvasGradient final
+    : public RefCounted<CanvasGradient>
+    , public Bindings::Wrappable {
+public:
+    using WrapperType = Bindings::CanvasGradientWrapper;
+
+    enum class Type {
+        Linear,
+        Radial,
+        Conic,
+    };
+
+    static NonnullRefPtr<CanvasGradient> create_radial(double x0, double y0, double r0, double x1, double y1, double r1);
+    static NonnullRefPtr<CanvasGradient> create_linear(double x0, double y0, double x1, double y1);
+    static NonnullRefPtr<CanvasGradient> create_conic(double start_angle, double x, double y);
+
+    void add_color_stop(double offset, String const& color);
+
+    ~CanvasGradient();
+
+private:
+    explicit CanvasGradient(Type);
+
+    Type m_type {};
+};
+
+}

Userland/Libraries/LibWeb/HTML/CanvasGradient.idl

@@ -0,0 +1,5 @@
+[Exposed=(Window,Worker)]
+interface CanvasGradient {
+    // opaque object
+    undefined addColorStop(double offset, DOMString color);
+};

Userland/Libraries/LibWeb/HTML/CanvasRenderingContext2D.cpp

@@ -496,4 +496,19 @@ CanvasRenderingContext2D::PreparedText CanvasRenderingContext2D::prepare_text(St
     return prepared_text;
 }
 
+NonnullRefPtr<CanvasGradient> CanvasRenderingContext2D::create_radial_gradient(double x0, double y0, double r0, double x1, double y1, double r1)
+{
+    return CanvasGradient::create_radial(x0, y0, r0, x1, y1, r1);
+}
+
+NonnullRefPtr<CanvasGradient> CanvasRenderingContext2D::create_linear_gradient(double x0, double y0, double x1, double y1)
+{
+    return CanvasGradient::create_linear(x0, y0, x1, y1);
+}
+
+NonnullRefPtr<CanvasGradient> CanvasRenderingContext2D::create_conic_gradient(double start_angle, double x, double y)
+{
+    return CanvasGradient::create_conic(start_angle, x, y);
+}
+
 }

Userland/Libraries/LibWeb/HTML/CanvasRenderingContext2D.h

@@ -14,6 +14,7 @@
 #include <LibGfx/Path.h>
 #include <LibWeb/Bindings/Wrappable.h>
 #include <LibWeb/DOM/ExceptionOr.h>
+#include <LibWeb/HTML/CanvasGradient.h>
 #include <LibWeb/Layout/InlineNode.h>
 #include <LibWeb/Layout/LineBox.h>
 
@@ -83,6 +84,10 @@ public:
 
     RefPtr<TextMetrics> measure_text(String const& text);
 
+    NonnullRefPtr<CanvasGradient> create_radial_gradient(double x0, double y0, double r0, double x1, double y1, double r1);
+    NonnullRefPtr<CanvasGradient> create_linear_gradient(double x0, double y0, double x1, double y1);
+    NonnullRefPtr<CanvasGradient> create_conic_gradient(double start_angle, double x, double y);
+
 private:
     explicit CanvasRenderingContext2D(HTMLCanvasElement&);
 

Userland/Libraries/LibWeb/HTML/CanvasRenderingContext2D.idl

@@ -40,4 +40,9 @@ interface CanvasRenderingContext2D {
     readonly attribute HTMLCanvasElement canvas;
 
     TextMetrics measureText(DOMString text);
+
+    CanvasGradient createRadialGradient(double x0, double y0, double r0, double x1, double y1, double r1);
+    CanvasGradient createLinearGradient(double x0, double y0, double x1, double y1);
+    CanvasGradient createConicGradient(double startAngle, double x, double y);
+
 };