From 28fabd4728a01a73118b7e721b30d783a14fee44 Mon Sep 17 00:00:00 2001
From: Andreas Kling <kling@serenityos.org>
Date: Wed, 15 Sep 2021 14:53:44 +0200
Subject: [PATCH] LibWeb: Make Layout::Node::paint() pure virtual

In the past, the base class implementation of this was used to descend
into subtrees and paint children. That is now taken care of by
StackingContext::paint_descendants() instead, and nothing used this.
---
 Userland/Libraries/LibWeb/Layout/BreakNode.cpp |  4 ++++
 Userland/Libraries/LibWeb/Layout/BreakNode.h   |  2 ++
 Userland/Libraries/LibWeb/Layout/Node.cpp      | 14 --------------
 Userland/Libraries/LibWeb/Layout/Node.h        |  2 +-
 Userland/Libraries/LibWeb/Layout/TextNode.cpp  |  4 ++++
 Userland/Libraries/LibWeb/Layout/TextNode.h    |  1 +
 6 files changed, 12 insertions(+), 15 deletions(-)

diff --git a/Userland/Libraries/LibWeb/Layout/BreakNode.cpp b/Userland/Libraries/LibWeb/Layout/BreakNode.cpp
index 2cd02d44a4..cbc1c543e1 100644
--- a/Userland/Libraries/LibWeb/Layout/BreakNode.cpp
+++ b/Userland/Libraries/LibWeb/Layout/BreakNode.cpp
@@ -26,4 +26,8 @@ void BreakNode::split_into_lines(InlineFormattingContext& context, LayoutMode)
     line_box.add_fragment(*this, 0, 0, 0, context.containing_block().line_height());
 }
 
+void BreakNode::paint(PaintContext&, PaintPhase)
+{
+}
+
 }
diff --git a/Userland/Libraries/LibWeb/Layout/BreakNode.h b/Userland/Libraries/LibWeb/Layout/BreakNode.h
index 873f55ae30..6d0bc97396 100644
--- a/Userland/Libraries/LibWeb/Layout/BreakNode.h
+++ b/Userland/Libraries/LibWeb/Layout/BreakNode.h
@@ -19,6 +19,8 @@ public:
     const HTML::HTMLBRElement& dom_node() const { return verify_cast<HTML::HTMLBRElement>(*Node::dom_node()); }
 
 private:
+    virtual void paint(PaintContext&, PaintPhase) override;
+
     virtual void split_into_lines(InlineFormattingContext&, LayoutMode) override;
 };
 
diff --git a/Userland/Libraries/LibWeb/Layout/Node.cpp b/Userland/Libraries/LibWeb/Layout/Node.cpp
index ba43029c98..8284060552 100644
--- a/Userland/Libraries/LibWeb/Layout/Node.cpp
+++ b/Userland/Libraries/LibWeb/Layout/Node.cpp
@@ -83,20 +83,6 @@ bool Node::establishes_stacking_context() const
     return false;
 }
 
-void Node::paint(PaintContext& context, PaintPhase phase)
-{
-    if (!is_visible())
-        return;
-
-    before_children_paint(context, phase);
-
-    for_each_child_in_paint_order([&](auto& child) {
-        child.paint(context, phase);
-    });
-
-    after_children_paint(context, phase);
-}
-
 HitTestResult Node::hit_test(const Gfx::IntPoint& position, HitTestType type) const
 {
     HitTestResult result;
diff --git a/Userland/Libraries/LibWeb/Layout/Node.h b/Userland/Libraries/LibWeb/Layout/Node.h
index 0825b7d99c..3fbffce705 100644
--- a/Userland/Libraries/LibWeb/Layout/Node.h
+++ b/Userland/Libraries/LibWeb/Layout/Node.h
@@ -92,7 +92,7 @@ public:
     virtual bool handle_mousewheel(Badge<EventHandler>, const Gfx::IntPoint&, unsigned buttons, unsigned modifiers, int wheel_delta);
 
     virtual void before_children_paint(PaintContext&, PaintPhase) {};
-    virtual void paint(PaintContext&, PaintPhase);
+    virtual void paint(PaintContext&, PaintPhase) = 0;
     virtual void paint_fragment(PaintContext&, const LineBoxFragment&, PaintPhase) const { }
     virtual void after_children_paint(PaintContext&, PaintPhase) {};
 
diff --git a/Userland/Libraries/LibWeb/Layout/TextNode.cpp b/Userland/Libraries/LibWeb/Layout/TextNode.cpp
index 53922dced1..13f005fcb4 100644
--- a/Userland/Libraries/LibWeb/Layout/TextNode.cpp
+++ b/Userland/Libraries/LibWeb/Layout/TextNode.cpp
@@ -414,4 +414,8 @@ Optional<TextNode::Chunk> TextNode::ChunkIterator::try_commit_chunk(Utf8View::It
     return {};
 }
 
+void TextNode::paint(PaintContext&, PaintPhase)
+{
+}
+
 }
diff --git a/Userland/Libraries/LibWeb/Layout/TextNode.h b/Userland/Libraries/LibWeb/Layout/TextNode.h
index 86bdb554b7..fe561fba58 100644
--- a/Userland/Libraries/LibWeb/Layout/TextNode.h
+++ b/Userland/Libraries/LibWeb/Layout/TextNode.h
@@ -63,6 +63,7 @@ private:
     void split_into_lines_by_rules(InlineFormattingContext&, LayoutMode, bool do_collapse, bool do_wrap_lines, bool do_respect_linebreaks);
     void paint_cursor_if_needed(PaintContext&, const LineBoxFragment&) const;
     void paint_text_decoration(Gfx::Painter&, LineBoxFragment const&) const;
+    virtual void paint(PaintContext&, PaintPhase) override;
 
     String m_text_for_rendering;
 };