Reuse text layout for performance

src/renderer/dx/CustomTextLayout.cpp

@@ -42,6 +42,16 @@ CustomTextLayout::CustomTextLayout(gsl::not_null<IDWriteFactory1*> const factory
     _localeName.resize(gsl::narrow_cast<size_t>(format->GetLocaleNameLength()) + 1); // +1 for null
     THROW_IF_FAILED(format->GetLocaleName(_localeName.data(), gsl::narrow<UINT32>(_localeName.size())));
 
+    SetData(clusters);
+}
+
+void CustomTextLayout::SetData(std::basic_string_view<Cluster> const clusters)
+{
+    _textClusterColumns.clear();
+    _runs.clear();
+    _runIndex = 0;
+    _text = L"";
+
     for (const auto& cluster : clusters)
     {
         const auto cols = gsl::narrow<UINT16>(cluster.GetColumns());

src/renderer/dx/CustomTextLayout.h

@@ -26,6 +26,8 @@ namespace Microsoft::Console::Render
                          const std::basic_string_view<::Microsoft::Console::Render::Cluster> clusters,
                          size_t const width);
 
+        void SetData(std::basic_string_view<Cluster> const clustor);
+
         [[nodiscard]] HRESULT STDMETHODCALLTYPE GetColumns(_Out_ UINT32* columns);
 
         // IDWriteTextLayout methods (but we don't actually want to implement them all, so just this one matching the existing interface)

src/renderer/dx/DxRenderer.cpp

@@ -4,7 +4,6 @@
 #include "precomp.h"
 
 #include "DxRenderer.hpp"
-#include "CustomTextLayout.h"
 
 #include "../../interactivity/win32/CustomWindowMessages.h"
 #include "../../types/inc/Viewport.hpp"
@@ -959,12 +958,20 @@ void DxEngine::_InvalidOr(RECT rc) noexcept
         origin.y = static_cast<float>(coord.Y * _glyphCell.cy);
 
         // Create the text layout
-        CustomTextLayout layout(_dwriteFactory.Get(),
-                                _dwriteTextAnalyzer.Get(),
-                                _dwriteTextFormat.Get(),
-                                _dwriteFontFace.Get(),
-                                clusters,
-                                _glyphCell.cx);
+        if (_drawingTextLayout == nullptr)
+        {
+            _drawingTextLayout = ::Microsoft::WRL::Details::Make<CustomTextLayout>(_dwriteFactory.Get(),
+                                                    _dwriteTextAnalyzer.Get(),
+                                                    _dwriteTextFormat.Get(),
+                                                    _dwriteFontFace.Get(),
+                                                    clusters,
+                                                    _glyphCell.cx);
+        }
+        else
+        {
+            _drawingTextLayout->SetData(clusters);
+        }
+
 
         // Get the baseline for this font as that's where we draw from
         DWRITE_LINE_SPACING spacing;
@@ -980,7 +987,7 @@ void DxEngine::_InvalidOr(RECT rc) noexcept
                                D2D1_DRAW_TEXT_OPTIONS_ENABLE_COLOR_FONT);
 
         // Layout then render the text
-        RETURN_IF_FAILED(layout.Draw(&context, _customRenderer.Get(), origin.x, origin.y));
+        RETURN_IF_FAILED(_drawingTextLayout->Draw(&context, _customRenderer.Get(), origin.x, origin.y));
     }
     CATCH_RETURN();
 
@@ -1274,6 +1281,8 @@ enum class CursorPaintType
 
         _glyphCell.cx = size.X;
         _glyphCell.cy = size.Y;
+
+        _drawingTextLayout = nullptr;
     }
     CATCH_RETURN();
 

src/renderer/dx/DxRenderer.hpp

@@ -22,6 +22,7 @@
 #include <wrl/client.h>
 
 #include "CustomTextRenderer.h"
+#include "CustomTextLayout.h"
 
 #include "../../types/inc/Viewport.hpp"
 
@@ -121,6 +122,7 @@ namespace Microsoft::Console::Render
 
         SIZE _displaySizePixels;
         SIZE _glyphCell;
+        ::Microsoft::WRL::ComPtr<CustomTextLayout> _drawingTextLayout;
 
         D2D1_COLOR_F _defaultForegroundColor;
         D2D1_COLOR_F _defaultBackgroundColor;