LibWeb+LibGfx: Remove Path::close_all_subpaths()

As it turns out, SkPath already behaves the way we need for SVG and HTML
canvas elements. Less work for us, yay! This removes a 5% item from the
profile when scrolling on https://imdb.com/

Note that there's a tiny screenshot test expectation change due to
minor antialiasing differences when we no longer do our redundant
subpath modifications.

Libraries/LibGfx/ImageFormats/TinyVGLoader.cpp

@@ -477,7 +477,6 @@ void TinyVGDecodedImageData::draw(Painter& painter) const
         auto draw_path = command.path;
         if (command.fill.has_value()) {
             auto fill_path = draw_path;
-            fill_path.close_all_subpaths();
             command.fill->visit(
                 [&](Color color) { painter.fill_path(fill_path, color, WindingRule::EvenOdd); },
                 [&](NonnullRefPtr<SVGGradientPaintStyle> const& style) {

Libraries/LibGfx/Path.h

@@ -25,7 +25,6 @@ public:
     virtual void clear() = 0;
     virtual void move_to(Gfx::FloatPoint const&) = 0;
     virtual void line_to(Gfx::FloatPoint const&) = 0;
-    virtual void close_all_subpaths() = 0;
     virtual void close() = 0;
     virtual void elliptical_arc_to(FloatPoint point, FloatSize radii, float x_axis_rotation, bool large_arc, bool sweep) = 0;
     virtual void arc_to(FloatPoint point, float radius, bool large_arc, bool sweep) = 0;
@@ -73,7 +72,6 @@ public:
     void clear() { impl().clear(); }
     void move_to(Gfx::FloatPoint const& point) { impl().move_to(point); }
     void line_to(Gfx::FloatPoint const& point) { impl().line_to(point); }
-    void close_all_subpaths() { impl().close_all_subpaths(); }
     void close() { impl().close(); }
 
     enum class CapStyle {

Libraries/LibGfx/PathSkia.cpp

@@ -57,51 +57,6 @@ void PathImplSkia::line_to(Gfx::FloatPoint const& point)
     m_path->lineTo(point.x(), point.y());
 }
 
-void PathImplSkia::close_all_subpaths()
-{
-    SkPath new_path;
-    SkPath::Iter iter(*m_path, false);
-    SkPoint points[4];
-    SkPath::Verb verb;
-    bool need_close = false;
-
-    while ((verb = iter.next(points)) != SkPath::kDone_Verb) {
-        switch (verb) {
-        case SkPath::kMove_Verb:
-            if (need_close) {
-                new_path.close();
-            }
-            new_path.moveTo(points[0]);
-            need_close = true;
-            break;
-        case SkPath::kLine_Verb:
-            new_path.lineTo(points[1]);
-            break;
-        case SkPath::kQuad_Verb:
-            new_path.quadTo(points[1], points[2]);
-            break;
-        case SkPath::kCubic_Verb:
-            new_path.cubicTo(points[1], points[2], points[3]);
-            break;
-        case SkPath::kClose_Verb:
-            new_path.close();
-            need_close = false;
-            break;
-        case SkPath::kConic_Verb:
-            new_path.conicTo(points[1], points[2], iter.conicWeight());
-            break;
-        case SkPath::kDone_Verb:
-            break;
-        }
-    }
-
-    if (need_close) {
-        new_path.close();
-    }
-
-    *m_path = new_path;
-}
-
 void PathImplSkia::close()
 {
     m_path->close();

Libraries/LibGfx/PathSkia.h

@@ -21,7 +21,6 @@ public:
     virtual void clear() override;
     virtual void move_to(Gfx::FloatPoint const&) override;
     virtual void line_to(Gfx::FloatPoint const&) override;
-    virtual void close_all_subpaths() override;
     virtual void close() override;
     virtual void elliptical_arc_to(FloatPoint point, FloatSize radii, float x_axis_rotation, bool large_arc, bool sweep) override;
     virtual void arc_to(FloatPoint point, float radius, bool large_arc, bool sweep) override;

Libraries/LibWeb/CSS/StyleValues/BasicShapeStyleValue.cpp

@@ -217,11 +217,6 @@ String Polygon::to_string(SerializationMode) const
 Gfx::Path Path::to_path(CSSPixelRect, Layout::Node const&) const
 {
     auto result = path_instructions.to_gfx_path();
-    // The UA must close a path with an implicit closepath command ("z" or "Z") if it is not present in the string for
-    // properties that require a closed loop (such as shape-outside and clip-path).
-    // https://drafts.csswg.org/css-shapes/#funcdef-basic-shape-path
-    // FIXME: For now, all users want a closed path, so we'll always close it.
-    result.close_all_subpaths();
     result.set_fill_type(fill_rule);
     return result;
 }

Libraries/LibWeb/HTML/CanvasRenderingContext2D.cpp

@@ -405,12 +405,10 @@ void CanvasRenderingContext2D::fill_internal(Gfx::Path const& path, Gfx::Winding
 
     paint_shadow_for_fill_internal(path, winding_rule);
 
-    auto path_to_fill = path;
-    path_to_fill.close_all_subpaths();
     auto& state = this->drawing_state();
-    painter->fill_path(path_to_fill, state.fill_style.to_gfx_paint_style(), state.filter, state.global_alpha, state.current_compositing_and_blending_operator, winding_rule);
+    painter->fill_path(path, state.fill_style.to_gfx_paint_style(), state.filter, state.global_alpha, state.current_compositing_and_blending_operator, winding_rule);
 
-    did_draw(path_to_fill.bounding_box());
+    did_draw(path.bounding_box());
 }
 
 void CanvasRenderingContext2D::fill(StringView fill_rule)
@@ -674,7 +672,6 @@ void CanvasRenderingContext2D::clip_internal(Gfx::Path& path, Gfx::WindingRule w
     if (!painter)
         return;
 
-    path.close_all_subpaths();
     painter->clip(path, winding_rule);
 }
 
@@ -968,9 +965,6 @@ void CanvasRenderingContext2D::paint_shadow_for_fill_internal(Gfx::Path const& p
     if (!painter)
         return;
 
-    auto path_to_fill = path;
-    path_to_fill.close_all_subpaths();
-
     auto& state = this->drawing_state();
 
     if (state.current_compositing_and_blending_operator == Gfx::CompositingAndBlendingOperator::Copy)
@@ -981,11 +975,11 @@ void CanvasRenderingContext2D::paint_shadow_for_fill_internal(Gfx::Path const& p
     Gfx::AffineTransform transform;
     transform.translate(state.shadow_offset_x, state.shadow_offset_y);
     painter->set_transform(transform);
-    painter->fill_path(path_to_fill, state.shadow_color.with_opacity(state.global_alpha), winding_rule, state.shadow_blur, state.current_compositing_and_blending_operator);
+    painter->fill_path(path, state.shadow_color.with_opacity(state.global_alpha), winding_rule, state.shadow_blur, state.current_compositing_and_blending_operator);
 
     painter->restore();
 
-    did_draw(path_to_fill.bounding_box());
+    did_draw(path.bounding_box());
 }
 
 void CanvasRenderingContext2D::paint_shadow_for_stroke_internal(Gfx::Path const& path)

Libraries/LibWeb/Painting/BorderPainting.cpp

@@ -282,7 +282,6 @@ void paint_border(DisplayListRecorder& painter, BorderEdge edge, DevicePixelRect
 
         // If joined borders have the same color, combine them to draw together.
         if (ready_to_draw) {
-            path.close_all_subpaths();
             painter.fill_path({ .path = path, .paint_style_or_color = color, .winding_rule = Gfx::WindingRule::EvenOdd });
             path.clear();
         }

Libraries/LibWeb/Painting/SVGPathPaintable.cpp

@@ -84,16 +84,6 @@ void SVGPathPaintable::paint(DisplayListRecordingContext& context, PaintPhase ph
     auto path = computed_path()->copy_transformed(paint_transform);
     path.offset(offset);
 
-    // Fills are computed as though all subpaths are closed (https://svgwg.org/svg2-draft/painting.html#FillProperties)
-    auto closed_path = [&] {
-        // We need to fill the path before applying the stroke, however the filled
-        // path must be closed, whereas the stroke path may not necessary be closed.
-        // Copy the path and close it for filling, but use the previous path for stroke
-        auto copy = path;
-        copy.close_all_subpaths();
-        return copy;
-    };
-
     auto svg_viewport = [&] {
         if (maybe_view_box.has_value())
             return Gfx::FloatRect { maybe_view_box->min_x, maybe_view_box->min_y, maybe_view_box->width, maybe_view_box->height };
@@ -106,7 +96,7 @@ void SVGPathPaintable::paint(DisplayListRecordingContext& context, PaintPhase ph
         // within a clipPath conceptually defines a 1-bit mask (with the possible exception of anti-aliasing along
         // the edge of the geometry) which represents the silhouette of the graphics associated with that element.
         context.display_list_recorder().fill_path({
-            .path = closed_path(),
+            .path = path,
             .paint_style_or_color = Gfx::Color(Color::Black),
             .winding_rule = to_gfx_winding_rule(graphics_element.clip_rule().value_or(SVG::ClipRule::Nonzero)),
             .should_anti_alias = should_anti_alias(),
@@ -125,7 +115,7 @@ void SVGPathPaintable::paint(DisplayListRecordingContext& context, PaintPhase ph
         auto winding_rule = to_gfx_winding_rule(graphics_element.fill_rule().value_or(SVG::FillRule::Nonzero));
         if (auto paint_style = graphics_element.fill_paint_style(paint_context); paint_style.has_value()) {
             context.display_list_recorder().fill_path({
-                .path = closed_path(),
+                .path = path,
                 .opacity = fill_opacity,
                 .paint_style_or_color = *paint_style,
                 .winding_rule = winding_rule,
@@ -133,7 +123,7 @@ void SVGPathPaintable::paint(DisplayListRecordingContext& context, PaintPhase ph
             });
         } else if (auto fill_color = graphics_element.fill_color(); fill_color.has_value()) {
             context.display_list_recorder().fill_path({
-                .path = closed_path(),
+                .path = path,
                 .paint_style_or_color = fill_color->with_opacity(fill_opacity),
                 .winding_rule = winding_rule,
                 .should_anti_alias = should_anti_alias(),

Tests/LibWeb/Screenshot/input/canvas-path-rect.html

@@ -1,6 +1,6 @@
 <!DOCTYPE html>
 <link rel="match" href="../expected/canvas-path-rect-ref.html" />
-<meta name="fuzzy" content="maxDifference=0-1;totalPixels=0-148">
+<meta name="fuzzy" content="maxDifference=0-1;totalPixels=0-158">
 <style>
   * {
     margin: 0;