LibWeb: Remove glyph run allocation in paint_text_fragment()

Instead of allocating a new glyph run to scale glyph positions and
fonts, a scale factor could be encoded in a paint command and applied
later during command execution.

Userland/Libraries/LibWeb/Painting/Command.cpp

@@ -11,12 +11,8 @@ namespace Web::Painting {
 
 void DrawGlyphRun::translate_by(Gfx::IntPoint const& offset)
 {
-    for (auto& glyph : glyph_run) {
-        glyph.visit([&](auto& glyph) {
-            glyph.translate_by(offset.to_type<float>());
-        });
-    }
     rect.translate_by(offset);
+    translation.translate_by(offset.to_type<float>());
 }
 
 Gfx::IntRect PaintOuterBoxShadow::bounding_rect() const

Userland/Libraries/LibWeb/Painting/Command.h

@@ -42,6 +42,7 @@ struct DrawGlyphRun {
     Color color;
     Gfx::IntRect rect;
     Gfx::FloatPoint translation;
+    double scale { 1 };
 
     [[nodiscard]] Gfx::IntRect bounding_rect() const { return rect; }
 

Userland/Libraries/LibWeb/Painting/CommandExecutorCPU.cpp

@@ -24,12 +24,15 @@ CommandExecutorCPU::CommandExecutorCPU(Gfx::Bitmap& bitmap)
         .scaling_mode = {} });
 }
 
-CommandResult CommandExecutorCPU::draw_glyph_run(Vector<Gfx::DrawGlyphOrEmoji> const& glyph_run, Color const& color, Gfx::FloatPoint translation)
+CommandResult CommandExecutorCPU::draw_glyph_run(Vector<Gfx::DrawGlyphOrEmoji> const& glyph_run, Color const& color, Gfx::FloatPoint translation, double scale)
 {
     auto& painter = this->painter();
     for (auto& glyph_or_emoji : glyph_run) {
         auto transformed_glyph = glyph_or_emoji;
-        transformed_glyph.visit([&](auto& glyph) { glyph.position.translate_by(translation); });
+        transformed_glyph.visit([&](auto& glyph) {
+            glyph.position = glyph.position.scaled(scale).translated(translation);
+            glyph.font = *glyph.font->with_size(glyph.font->point_size() * static_cast<float>(scale));
+        });
         if (glyph_or_emoji.has<Gfx::DrawGlyph>()) {
             auto& glyph = transformed_glyph.get<Gfx::DrawGlyph>();
             painter.draw_glyph(glyph.position, glyph.code_point, *glyph.font, color);

Userland/Libraries/LibWeb/Painting/CommandExecutorCPU.h

@@ -13,7 +13,7 @@ namespace Web::Painting {
 
 class CommandExecutorCPU : public CommandExecutor {
 public:
-    CommandResult draw_glyph_run(Vector<Gfx::DrawGlyphOrEmoji> const& glyph_run, Color const&, Gfx::FloatPoint translation) override;
+    CommandResult draw_glyph_run(Vector<Gfx::DrawGlyphOrEmoji> const& glyph_run, Color const&, Gfx::FloatPoint translation, double scale) override;
     CommandResult draw_text(Gfx::IntRect const& rect, String const& raw_text, Gfx::TextAlignment alignment, Color const&, Gfx::TextElision, Gfx::TextWrapping, Optional<NonnullRefPtr<Gfx::Font>> const&) override;
     CommandResult fill_rect(Gfx::IntRect const& rect, Color const&) override;
     CommandResult draw_scaled_bitmap(Gfx::IntRect const& dst_rect, Gfx::Bitmap const& bitmap, Gfx::IntRect const& src_rect, Gfx::Painter::ScalingMode scaling_mode) override;

Userland/Libraries/LibWeb/Painting/CommandExecutorGPU.cpp

@@ -31,13 +31,16 @@ CommandExecutorGPU::~CommandExecutorGPU()
     painter().flush(m_target_bitmap);
 }
 
-CommandResult CommandExecutorGPU::draw_glyph_run(Vector<Gfx::DrawGlyphOrEmoji> const& glyph_run, Color const& color, Gfx::FloatPoint translation)
+CommandResult CommandExecutorGPU::draw_glyph_run(Vector<Gfx::DrawGlyphOrEmoji> const& glyph_run, Color const& color, Gfx::FloatPoint translation, double scale)
 {
     Vector<Gfx::DrawGlyphOrEmoji> transformed_glyph_run;
     transformed_glyph_run.ensure_capacity(glyph_run.size());
     for (auto& glyph : glyph_run) {
         auto transformed_glyph = glyph;
-        transformed_glyph.visit([&](auto& glyph) { glyph.position.translate_by(translation); });
+        transformed_glyph.visit([&](auto& glyph) {
+            glyph.position = glyph.position.scaled(scale).translated(translation);
+            glyph.font = *glyph.font->with_size(glyph.font->point_size() * static_cast<float>(scale));
+        });
         transformed_glyph_run.append(transformed_glyph);
     }
     painter().draw_glyph_run(transformed_glyph_run, color);

Userland/Libraries/LibWeb/Painting/CommandExecutorGPU.h

@@ -14,7 +14,7 @@ namespace Web::Painting {
 
 class CommandExecutorGPU : public CommandExecutor {
 public:
-    CommandResult draw_glyph_run(Vector<Gfx::DrawGlyphOrEmoji> const& glyph_run, Color const&, Gfx::FloatPoint translation) override;
+    CommandResult draw_glyph_run(Vector<Gfx::DrawGlyphOrEmoji> const& glyph_run, Color const&, Gfx::FloatPoint translation, double scale) override;
     CommandResult draw_text(Gfx::IntRect const& rect, String const& raw_text, Gfx::TextAlignment alignment, Color const&, Gfx::TextElision, Gfx::TextWrapping, Optional<NonnullRefPtr<Gfx::Font>> const&) override;
     CommandResult fill_rect(Gfx::IntRect const& rect, Color const&) override;
     CommandResult draw_scaled_bitmap(Gfx::IntRect const& dst_rect, Gfx::Bitmap const& bitmap, Gfx::IntRect const& src_rect, Gfx::Painter::ScalingMode scaling_mode) override;

Userland/Libraries/LibWeb/Painting/CommandList.cpp

@@ -48,10 +48,12 @@ void CommandList::execute(CommandExecutor& executor)
         for (auto& command_with_scroll_id : m_commands) {
             auto& command = command_with_scroll_id.command;
             if (command.has<DrawGlyphRun>()) {
+                auto scale = command.get<DrawGlyphRun>().scale;
                 for (auto const& glyph_or_emoji : command.get<DrawGlyphRun>().glyph_run) {
                     if (glyph_or_emoji.has<Gfx::DrawGlyph>()) {
                         auto const& glyph = glyph_or_emoji.get<Gfx::DrawGlyph>();
-                        unique_glyphs.ensure(glyph.font, [] { return HashTable<u32> {}; }).set(glyph.code_point);
+                        auto const& font = *glyph.font->with_size(glyph.font->point_size() * static_cast<float>(scale));
+                        unique_glyphs.ensure(&font, [] { return HashTable<u32> {}; }).set(glyph.code_point);
                     }
                 }
             }
@@ -87,7 +89,7 @@ void CommandList::execute(CommandExecutor& executor)
 
         auto result = command.visit(
             [&](DrawGlyphRun const& command) {
-                return executor.draw_glyph_run(command.glyph_run, command.color, command.translation);
+                return executor.draw_glyph_run(command.glyph_run, command.color, command.translation, command.scale);
             },
             [&](DrawText const& command) {
                 return executor.draw_text(command.rect, command.raw_text, command.alignment, command.color,

Userland/Libraries/LibWeb/Painting/CommandList.h

@@ -47,7 +47,7 @@ class CommandExecutor {
 public:
     virtual ~CommandExecutor() = default;
 
-    virtual CommandResult draw_glyph_run(Vector<Gfx::DrawGlyphOrEmoji> const& glyph_run, Color const&, Gfx::FloatPoint translation) = 0;
+    virtual CommandResult draw_glyph_run(Vector<Gfx::DrawGlyphOrEmoji> const& glyph_run, Color const&, Gfx::FloatPoint translation, double scale) = 0;
     virtual CommandResult draw_text(Gfx::IntRect const&, String const&, Gfx::TextAlignment alignment, Color const&, Gfx::TextElision, Gfx::TextWrapping, Optional<NonnullRefPtr<Gfx::Font>> const&) = 0;
     virtual CommandResult fill_rect(Gfx::IntRect const&, Color const&) = 0;
     virtual CommandResult draw_scaled_bitmap(Gfx::IntRect const& dst_rect, Gfx::Bitmap const& bitmap, Gfx::IntRect const& src_rect, Gfx::Painter::ScalingMode scaling_mode) = 0;

Userland/Libraries/LibWeb/Painting/PaintableBox.cpp

@@ -668,23 +668,15 @@ void paint_text_fragment(PaintContext& context, Layout::TextNode const& text_nod
         auto text = text_node.text_for_rendering();
 
         DevicePixelPoint baseline_start { fragment_absolute_device_rect.x(), fragment_absolute_device_rect.y() + context.rounded_device_pixels(fragment.baseline()) };
-        Vector<Gfx::DrawGlyphOrEmoji> scaled_glyph_run;
+        auto scale = context.device_pixels_per_css_pixel();
-        scaled_glyph_run.ensure_capacity(fragment.glyph_run().size());
+        painter.draw_text_run(baseline_start.to_type<int>(), fragment.glyph_run(), text_node.computed_values().color(), fragment_absolute_device_rect.to_type<int>(), scale);
-        for (auto glyph : fragment.glyph_run()) {
-            glyph.visit([&](auto& glyph) {
-                glyph.font = *glyph.font->with_size(glyph.font->point_size() * static_cast<float>(context.device_pixels_per_css_pixel()));
-                glyph.position = glyph.position.scaled(context.device_pixels_per_css_pixel());
-            });
-            scaled_glyph_run.append(move(glyph));
-        }
-        painter.draw_text_run(baseline_start.to_type<int>(), scaled_glyph_run, text_node.computed_values().color(), fragment_absolute_device_rect.to_type<int>());
 
         auto selection_rect = context.enclosing_device_rect(fragment.selection_rect(text_node.first_available_font())).to_type<int>();
         if (!selection_rect.is_empty()) {
             painter.fill_rect(selection_rect, CSS::SystemColor::highlight());
             RecordingPainterStateSaver saver(painter);
             painter.add_clip_rect(selection_rect);
-            painter.draw_text_run(baseline_start.to_type<int>(), scaled_glyph_run, CSS::SystemColor::highlight_text(), fragment_absolute_device_rect.to_type<int>());
+            painter.draw_text_run(baseline_start.to_type<int>(), fragment.glyph_run(), CSS::SystemColor::highlight_text(), fragment_absolute_device_rect.to_type<int>(), scale);
         }
 
         paint_text_decoration(context, text_node, fragment);

Userland/Libraries/LibWeb/Painting/RecordingPainter.cpp

@@ -206,7 +206,7 @@ void RecordingPainter::draw_signed_distance_field(Gfx::IntRect const& dst_rect,
     });
 }
 
-void RecordingPainter::draw_text_run(Gfx::IntPoint baseline_start, Span<Gfx::DrawGlyphOrEmoji const> glyph_run, Color color, Gfx::IntRect const& rect)
+void RecordingPainter::draw_text_run(Gfx::IntPoint baseline_start, Span<Gfx::DrawGlyphOrEmoji const> glyph_run, Color color, Gfx::IntRect const& rect, double scale)
 {
     auto transformed_baseline_start = state().translation.map(baseline_start).to_type<float>();
     append(DrawGlyphRun {
@@ -214,6 +214,7 @@ void RecordingPainter::draw_text_run(Gfx::IntPoint baseline_start, Span<Gfx::Dra
         .color = color,
         .rect = state().translation.map(rect),
         .translation = transformed_baseline_start,
+        .scale = scale,
     });
 }
 

Userland/Libraries/LibWeb/Painting/RecordingPainter.h

@@ -100,7 +100,7 @@ public:
     void draw_signed_distance_field(Gfx::IntRect const& dst_rect, Color color, Gfx::GrayscaleBitmap const& sdf, float smoothing);
 
     // Streamlined text drawing routine that does no wrapping/elision/alignment.
-    void draw_text_run(Gfx::IntPoint baseline_start, Span<Gfx::DrawGlyphOrEmoji const> glyph_run, Color color, Gfx::IntRect const& rect);
+    void draw_text_run(Gfx::IntPoint baseline_start, Span<Gfx::DrawGlyphOrEmoji const> glyph_run, Color color, Gfx::IntRect const& rect, double scale);
 
     void add_clip_rect(Gfx::IntRect const& rect);