LibWeb: Implement <feImage> SVG filter

Author: https://github.com/tcl3 Commit: d4f05bc4ef Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/5856 Reviewed-by: https://github.com/AtkinsSJ ✅ Reviewed-by: https://github.com/gmta
2025-10-21 07:29:53 +00:00 · 2025-08-06 22:52:29 +01:00 · 2025-08-06 22:52:29 +01:00 · d4f05bc4ef · 2025-08-29 09:16:34 +00:00
commit d4f05bc4ef
parent 5eff541804
19 changed files with 242 additions and 3 deletions
--- a/Libraries/LibWeb/SVG/SVGFEImageElement.cpp
+++ b/Libraries/LibWeb/SVG/SVGFEImageElement.cpp
@ -0,0 +1,113 @@
+/*
+ * Copyright (c) 2025, Tim Ledbetter <tim.ledbetter@gmail.com>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include "SVGFEImageElement.h"
+#include <LibCore/Timer.h>
+#include <LibGfx/ImmutableBitmap.h>
+#include <LibWeb/Bindings/SVGFEImageElementPrototype.h>
+#include <LibWeb/HTML/DecodedImageData.h>
+#include <LibWeb/HTML/PotentialCORSRequest.h>
+#include <LibWeb/HTML/SharedResourceRequest.h>
+#include <LibWeb/Layout/SVGImageBox.h>
+#include <LibWeb/Namespace.h>
+
+namespace Web::SVG {
+
+GC_DEFINE_ALLOCATOR(SVGFEImageElement);
+
+SVGFEImageElement::SVGFEImageElement(DOM::Document& document, DOM::QualifiedName qualified_name)
+    : SVGElement(document, qualified_name)
+{
+}
+
+void SVGFEImageElement::initialize(JS::Realm& realm)
+{
+    WEB_SET_PROTOTYPE_FOR_INTERFACE(SVGFEImageElement);
+    Base::initialize(realm);
+}
+
+void SVGFEImageElement::visit_edges(Cell::Visitor& visitor)
+{
+    Base::visit_edges(visitor);
+    SVGFilterPrimitiveStandardAttributes::visit_edges(visitor);
+    SVGURIReferenceMixin::visit_edges(visitor);
+    visitor.visit(m_resource_request);
+}
+
+void SVGFEImageElement::attribute_changed(FlyString const& name, Optional<String> const& old_value, Optional<String> const& value, Optional<FlyString> const& namespace_)
+{
+    Base::attribute_changed(name, old_value, value, namespace_);
+
+    if (name == SVG::AttributeNames::href) {
+        if (namespace_ == Namespace::XLink && has_attribute_ns({}, name))
+            return;
+
+        auto href = value;
+        if (!namespace_.has_value() && !href.has_value())
+            href = get_attribute_ns(SVG::AttributeNames::href, Namespace::XLink);
+
+        process_href(href);
+    }
+}
+
+void SVGFEImageElement::process_href(Optional<String> const& href)
+{
+    if (!href.has_value()) {
+        m_href = {};
+        return;
+    }
+
+    m_href = document().encoding_parse_url(*href);
+    if (!m_href.has_value())
+        return;
+
+    m_resource_request = HTML::SharedResourceRequest::get_or_create(realm(), document().page(), *m_href);
+    m_resource_request->add_callbacks(
+        [this, resource_request = GC::Root { m_resource_request }] {
+            set_needs_style_update(true);
+            if (auto layout_node = this->layout_node())
+                layout_node->set_needs_layout_update(DOM::SetNeedsLayoutReason::SVGImageFilterFetch);
+        },
+        nullptr);
+
+    if (m_resource_request->needs_fetching()) {
+        auto request = HTML::create_potential_CORS_request(vm(), *m_href, Fetch::Infrastructure::Request::Destination::Image, HTML::CORSSettingAttribute::NoCORS);
+        request->set_client(&document().relevant_settings_object());
+        m_resource_request->fetch_resource(realm(), request);
+    }
+}
+
+RefPtr<Gfx::ImmutableBitmap> SVGFEImageElement::current_image_bitmap(Gfx::IntSize size) const
+{
+    if (!m_resource_request)
+        return {};
+    if (auto data = m_resource_request->image_data())
+        return data->bitmap(0, size);
+    return {};
+}
+
+Optional<Gfx::IntRect> SVGFEImageElement::content_rect() const
+{
+    auto bitmap = current_image_bitmap();
+    if (!bitmap)
+        return {};
+    auto layout_node = this->layout_node();
+    if (!layout_node)
+        return {};
+    auto width = layout_node->computed_values().width().to_px(*layout_node, 0);
+    if (width == 0)
+        width = bitmap->width();
+
+    auto height = layout_node->computed_values().height().to_px(*layout_node, 0);
+    if (height == 0)
+        height = bitmap->height();
+
+    auto x = layout_node->computed_values().x().to_px(*layout_node, 0);
+    auto y = layout_node->computed_values().y().to_px(*layout_node, 0);
+    return Gfx::enclosing_int_rect({ x, y, width, height });
+}
+
+}