From 76e77deeccd93401999bd40f09bed91548f026ce Mon Sep 17 00:00:00 2001
From: Carlos Zamora <cazamor@microsoft.com>
Date: Fri, 30 Jul 2021 17:46:42 -0700
Subject: [PATCH 01/10] Add selection marker overlays for keyboard selection

---
 src/cascadia/TerminalControl/ControlCore.cpp  | 26 ++++++
 src/cascadia/TerminalControl/ControlCore.h    |  4 +
 src/cascadia/TerminalControl/ControlCore.idl  |  4 +
 src/cascadia/TerminalControl/EventArgs.cpp    |  1 +
 src/cascadia/TerminalControl/EventArgs.h      | 13 +++
 src/cascadia/TerminalControl/EventArgs.idl    |  6 +-
 src/cascadia/TerminalControl/TermControl.cpp  | 92 +++++++++++++++++--
 src/cascadia/TerminalControl/TermControl.h    |  3 +
 src/cascadia/TerminalControl/TermControl.xaml | 17 ++++
 src/cascadia/TerminalCore/Terminal.hpp        |  3 +
 .../TerminalCore/TerminalSelection.cpp        | 45 +++++++--
 11 files changed, 197 insertions(+), 17 deletions(-)

diff --git a/src/cascadia/TerminalControl/ControlCore.cpp b/src/cascadia/TerminalControl/ControlCore.cpp
index a224ca22c4d..5b538ce4755 100644
--- a/src/cascadia/TerminalControl/ControlCore.cpp
+++ b/src/cascadia/TerminalControl/ControlCore.cpp
@@ -409,6 +409,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
                 auto lock = _terminal->LockForWriting();
                 _terminal->UpdateSelection(updateSlnParams->first, updateSlnParams->second, modifiers);
                 _renderer->TriggerSelection();
+                _UpdateSelectionMarkersHandlers(*this, winrt::make<implementation::UpdateSelectionMarkersEventArgs>(false));
                 return true;
             }
 
@@ -417,6 +418,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
             {
                 _terminal->ClearSelection();
                 _renderer->TriggerSelection();
+                _UpdateSelectionMarkersHandlers(*this, winrt::make<implementation::UpdateSelectionMarkersEventArgs>(true));
             }
 
             // When there is a selection active, escape should clear it and NOT flow through
@@ -912,6 +914,26 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         _terminal->SetSelectionAnchor(position.to_win32_coord());
     }
 
+    Core::Point ControlCore::SelectionAnchor() const
+    {
+        auto lock = _terminal->LockForReading();
+        const auto start = _terminal->SelectionStartForRendering();
+        return { start.X, start.Y };
+    }
+
+    Core::Point ControlCore::SelectionEnd() const
+    {
+        auto lock = _terminal->LockForReading();
+        const auto end = _terminal->SelectionEndForRendering();
+        return { end.X, end.Y };
+    }
+
+    bool ControlCore::MovingStart() const
+    {
+        auto lock = _terminal->LockForReading();
+        return _terminal->MovingStart();
+    }
+
     // Method Description:
     // - Sets selection's end position to match supplied cursor position, e.g. while mouse dragging.
     // Arguments:
@@ -935,6 +957,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         // save location (for rendering) + render
         _terminal->SetSelectionEnd(terminalPosition.to_win32_coord());
         _renderer->TriggerSelection();
+        _UpdateSelectionMarkersHandlers(*this, winrt::make<implementation::UpdateSelectionMarkersEventArgs>(true));
     }
 
     // Called when the Terminal wants to set something to the clipboard, i.e.
@@ -997,6 +1020,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         {
             _terminal->ClearSelection();
             _renderer->TriggerSelection();
+            _UpdateSelectionMarkersHandlers(*this, winrt::make<implementation::UpdateSelectionMarkersEventArgs>(true));
         }
 
         // send data up for clipboard
@@ -1351,6 +1375,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
             _terminal->SetBlockSelection(false);
             search.Select();
             _renderer->TriggerSelection();
+            _UpdateSelectionMarkersHandlers(*this, winrt::make<implementation::UpdateSelectionMarkersEventArgs>(true));
         }
 
         // Raise a FoundMatch event, which the control will use to notify
@@ -1553,6 +1578,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         }
 
         _renderer->TriggerSelection();
+        _UpdateSelectionMarkersHandlers(*this, winrt::make<implementation::UpdateSelectionMarkersEventArgs>(true));
     }
 
     void ControlCore::AttachUiaEngine(::Microsoft::Console::Render::IRenderEngine* const pEngine)
diff --git a/src/cascadia/TerminalControl/ControlCore.h b/src/cascadia/TerminalControl/ControlCore.h
index 9cf4355a6ce..59733bcb2f9 100644
--- a/src/cascadia/TerminalControl/ControlCore.h
+++ b/src/cascadia/TerminalControl/ControlCore.h
@@ -151,6 +151,9 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         bool HasSelection() const;
         bool CopyOnSelect() const;
         Windows::Foundation::Collections::IVector<winrt::hstring> SelectedText(bool trimTrailingWhitespace) const;
+        Core::Point SelectionAnchor() const;
+        Core::Point SelectionEnd() const;
+        bool MovingStart() const;
         void SetSelectionAnchor(const til::point& position);
         void SetEndSelectionPoint(const til::point& position);
 
@@ -208,6 +211,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         TYPED_EVENT(ReceivedOutput,            IInspectable, IInspectable);
         TYPED_EVENT(FoundMatch,                IInspectable, Control::FoundResultsArgs);
         TYPED_EVENT(ShowWindowChanged,         IInspectable, Control::ShowWindowArgs);
+        TYPED_EVENT(UpdateSelectionMarkers,    IInspectable, Control::UpdateSelectionMarkersEventArgs);
         // clang-format on
 
     private:
diff --git a/src/cascadia/TerminalControl/ControlCore.idl b/src/cascadia/TerminalControl/ControlCore.idl
index edcb9fb69b1..e80ffdbe3da 100644
--- a/src/cascadia/TerminalControl/ControlCore.idl
+++ b/src/cascadia/TerminalControl/ControlCore.idl
@@ -90,6 +90,9 @@ namespace Microsoft.Terminal.Control
 
         Boolean HasSelection { get; };
         IVector<String> SelectedText(Boolean trimTrailingWhitespace);
+        Microsoft.Terminal.Core.Point SelectionAnchor { get; };
+        Microsoft.Terminal.Core.Point SelectionEnd { get; };
+        Boolean MovingStart { get; };
 
         String HoveredUriText { get; };
         Windows.Foundation.IReference<Microsoft.Terminal.Core.Point> HoveredCell { get; };
@@ -125,6 +128,7 @@ namespace Microsoft.Terminal.Control
         event Windows.Foundation.TypedEventHandler<Object, Object> ReceivedOutput;
         event Windows.Foundation.TypedEventHandler<Object, FoundResultsArgs> FoundMatch;
         event Windows.Foundation.TypedEventHandler<Object, ShowWindowArgs> ShowWindowChanged;
+        event Windows.Foundation.TypedEventHandler<Object, UpdateSelectionMarkersEventArgs> UpdateSelectionMarkers;
 
     };
 }
diff --git a/src/cascadia/TerminalControl/EventArgs.cpp b/src/cascadia/TerminalControl/EventArgs.cpp
index 665ea17f448..9f9b41ac1f7 100644
--- a/src/cascadia/TerminalControl/EventArgs.cpp
+++ b/src/cascadia/TerminalControl/EventArgs.cpp
@@ -13,3 +13,4 @@
 #include "TransparencyChangedEventArgs.g.cpp"
 #include "FoundResultsArgs.g.cpp"
 #include "ShowWindowArgs.g.cpp"
+#include "UpdateSelectionMarkersEventArgs.g.cpp"
diff --git a/src/cascadia/TerminalControl/EventArgs.h b/src/cascadia/TerminalControl/EventArgs.h
index 0d7c6d4a005..edefb2b0045 100644
--- a/src/cascadia/TerminalControl/EventArgs.h
+++ b/src/cascadia/TerminalControl/EventArgs.h
@@ -13,6 +13,8 @@
 #include "TransparencyChangedEventArgs.g.h"
 #include "FoundResultsArgs.g.h"
 #include "ShowWindowArgs.g.h"
+#include "UpdateSelectionMarkersEventArgs.g.h"
+#include "cppwinrt_utils.h" // TODO CARLOS: maybe we can remove this include?
 
 namespace winrt::Microsoft::Terminal::Control::implementation
 {
@@ -157,4 +159,15 @@ namespace winrt::Microsoft::Terminal::Control::implementation
 
         WINRT_PROPERTY(bool, ShowOrHide);
     };
+
+    struct UpdateSelectionMarkersEventArgs : public UpdateSelectionMarkersEventArgsT<UpdateSelectionMarkersEventArgs>
+    {
+    public:
+        UpdateSelectionMarkersEventArgs(const bool clearMarkers) :
+            _ClearMarkers(clearMarkers)
+        {
+        }
+
+        WINRT_PROPERTY(bool, ClearMarkers, false);
+    };
 }
diff --git a/src/cascadia/TerminalControl/EventArgs.idl b/src/cascadia/TerminalControl/EventArgs.idl
index 62ed095c8f4..941384c5b05 100644
--- a/src/cascadia/TerminalControl/EventArgs.idl
+++ b/src/cascadia/TerminalControl/EventArgs.idl
@@ -69,7 +69,6 @@ namespace Microsoft.Terminal.Control
         Double Opacity { get; };
     }
 
-
     runtimeclass FoundResultsArgs
     {
         Boolean FoundMatch { get; };
@@ -79,4 +78,9 @@ namespace Microsoft.Terminal.Control
     {
         Boolean ShowOrHide { get; };
     }
+    
+    runtimeclass UpdateSelectionMarkersEventArgs
+    {
+        Boolean ClearMarkers { get; };
+    }
 }
diff --git a/src/cascadia/TerminalControl/TermControl.cpp b/src/cascadia/TerminalControl/TermControl.cpp
index 37e4ad8096e..da156b3c6ad 100644
--- a/src/cascadia/TerminalControl/TermControl.cpp
+++ b/src/cascadia/TerminalControl/TermControl.cpp
@@ -83,6 +83,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         _core.RaiseNotice({ this, &TermControl::_coreRaisedNotice });
         _core.HoveredHyperlinkChanged({ this, &TermControl::_hoveredHyperlinkChanged });
         _core.FoundMatch({ this, &TermControl::_coreFoundMatch });
+        _core.UpdateSelectionMarkers({ this, &TermControl::_updateSelectionMarkers });
         _interactivity.OpenHyperlink({ this, &TermControl::_HyperlinkHandler });
         _interactivity.ScrollPositionChanged({ this, &TermControl::_ScrollPositionChanged });
 
@@ -320,6 +321,11 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         // switch from a solid color brush to an acrylic one.
         _changeBackgroundColor(bg);
 
+        // Update selection markers
+        Windows::UI::Xaml::Media::SolidColorBrush selectionBackgroundBrush{ til::color{ newAppearance.SelectionBackground() } };
+        SelectionStartIcon().Foreground(selectionBackgroundBrush);
+        SelectionEndIcon().Foreground(selectionBackgroundBrush);
+
         // Set TSF Foreground
         Media::SolidColorBrush foregroundBrush{};
         if (_core.Settings().UseBackgroundImageForWindow())
@@ -1786,6 +1792,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         update.newValue = args.ViewTop();
 
         _updateScrollBar->Run(update);
+        _updateSelectionMarkers(nullptr, winrt::make<UpdateSelectionMarkersEventArgs>(false));
     }
 
     // Method Description:
@@ -2685,8 +2692,8 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         _core.ClearHoveredCell();
     }
 
-    winrt::fire_and_forget TermControl::_hoveredHyperlinkChanged(IInspectable sender,
-                                                                 IInspectable args)
+    winrt::fire_and_forget TermControl::_hoveredHyperlinkChanged(IInspectable /*sender*/,
+                                                                 IInspectable /*args*/)
     {
         auto weakThis{ get_weak() };
         co_await wil::resume_foreground(Dispatcher());
@@ -2713,12 +2720,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
                     HyperlinkTooltipBorder().BorderThickness(newThickness);
 
                     // Compute the location of the top left corner of the cell in DIPS
-                    const til::size marginsInDips{ til::math::rounding, GetPadding().Left, GetPadding().Top };
-                    const til::point startPos{ lastHoveredCell.Value() };
-                    const til::size fontSize{ til::math::rounding, _core.FontSize() };
-                    const auto posInPixels{ startPos * fontSize };
-                    const til::point posInDIPs{ til::math::flooring, posInPixels.x / scale, posInPixels.y / scale };
-                    const auto locationInDIPs{ posInDIPs + marginsInDips };
+                    const til::point locationInDIPs{ _toPosInDips(lastHoveredCell.Value()) };
 
                     // Move the border to the top left corner of the cell
                     OverlayCanvas().SetLeft(HyperlinkTooltipBorder(), locationInDIPs.x - offset.x);
@@ -2728,10 +2730,84 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         }
     }
 
+    winrt::fire_and_forget TermControl::_updateSelectionMarkers(IInspectable /*sender*/, Control::UpdateSelectionMarkersEventArgs args)
+    {
+        auto weakThis{ get_weak() };
+        co_await resume_foreground(Dispatcher());
+        if (weakThis.get() && args)
+        {
+            if (_core.HasSelection() && !args.ClearMarkers())
+            {
+                // show/update selection markers
+                // figure out which endpoint to move, get it and the relevant icon (hide the other icon)
+                const auto movingStart{ _core.MovingStart() };
+                const auto selectionAnchor{ movingStart ? _core.SelectionAnchor() : _core.SelectionEnd() };
+                const auto& icon{ movingStart ? SelectionStartIcon() : SelectionEndIcon() };
+                const auto& otherIcon{ movingStart ? SelectionEndIcon() : SelectionStartIcon() };
+                if (selectionAnchor.Y < 0 || selectionAnchor.Y >= _core.ViewHeight())
+                {
+                    // if the endpoint is outside of the viewport,
+                    // just hide the markers
+                    icon.Opacity(0);
+                    otherIcon.Opacity(0);
+                    co_return;
+                }
+                else
+                {
+                    icon.Opacity(1);
+                    otherIcon.Opacity(0);
+                }
+
+                // Compute the location of the top left corner of the cell in DIPS
+                const til::point locationInDIPs{ _toPosInDips(selectionAnchor) };
+
+                // Move the icon to the top left corner of the cell
+                SelectionCanvas().SetLeft(icon,
+                                          (locationInDIPs.x - SwapChainPanel().ActualOffset().x));
+                SelectionCanvas().SetTop(icon,
+                                         (locationInDIPs.y - SwapChainPanel().ActualOffset().y));
+            }
+            else
+            {
+                // hide selection markers
+                SelectionStartIcon().Opacity(0);
+                SelectionEndIcon().Opacity(0);
+            }
+        }
+    }
+
+    til::point TermControl::_toPosInDips(const Core::Point terminalCellPos)
+    {
+        const til::point terminalPos{ terminalCellPos };
+        const til::size marginsInDips{ til::math::rounding, GetPadding().Left, GetPadding().Top };
+        const til::size fontSize{ til::math::rounding, _core.FontSize() };
+        const til::point posInPixels{ terminalPos * fontSize };
+        const auto scale{ SwapChainPanel().CompositionScaleX() };
+        const til::point posInDIPs{ til::math::flooring, posInPixels.x / scale, posInPixels.y / scale };
+        return posInDIPs + marginsInDips;
+    }
+
     void TermControl::_coreFontSizeChanged(const int fontWidth,
                                            const int fontHeight,
                                            const bool isInitialChange)
     {
+        // scale the selection markers to be the size of a cell
+        auto scaleIconMarker = [fontWidth, fontHeight](Windows::UI::Xaml::Controls::FontIcon icon) {
+            const auto size{ icon.DesiredSize() };
+            const auto scaleX = fontWidth / size.Width;
+            const auto scaleY = fontHeight / size.Height;
+
+            Windows::UI::Xaml::Media::ScaleTransform transform{};
+            transform.ScaleX(transform.ScaleX() * scaleX);
+            transform.ScaleY(transform.ScaleY() * scaleY);
+            icon.RenderTransform(transform);
+
+            // now hide the icon
+            icon.Opacity(0);
+        };
+        scaleIconMarker(SelectionStartIcon());
+        scaleIconMarker(SelectionEndIcon());
+
         // Don't try to inspect the core here. The Core is raising this while
         // it's holding its write lock. If the handlers calls back to some
         // method on the TermControl on the same thread, and that _method_ calls
diff --git a/src/cascadia/TerminalControl/TermControl.h b/src/cascadia/TerminalControl/TermControl.h
index b8d70e7741f..a3c881fb62e 100644
--- a/src/cascadia/TerminalControl/TermControl.h
+++ b/src/cascadia/TerminalControl/TermControl.h
@@ -278,6 +278,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         void _FontInfoHandler(const IInspectable& sender, const FontInfoEventArgs& eventArgs);
 
         winrt::fire_and_forget _hoveredHyperlinkChanged(IInspectable sender, IInspectable args);
+        winrt::fire_and_forget _updateSelectionMarkers(IInspectable sender, Control::UpdateSelectionMarkersEventArgs args);
 
         void _coreFontSizeChanged(const int fontWidth,
                                   const int fontHeight,
@@ -286,6 +287,8 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         void _coreRaisedNotice(const IInspectable& s, const Control::NoticeEventArgs& args);
         void _coreWarningBell(const IInspectable& sender, const IInspectable& args);
         void _coreFoundMatch(const IInspectable& sender, const Control::FoundResultsArgs& args);
+
+        til::point _toPosInDips(const Core::Point terminalCellPos);
     };
 }
 
diff --git a/src/cascadia/TerminalControl/TermControl.xaml b/src/cascadia/TerminalControl/TermControl.xaml
index 94afdb9c438..71f97be53b3 100644
--- a/src/cascadia/TerminalControl/TermControl.xaml
+++ b/src/cascadia/TerminalControl/TermControl.xaml
@@ -1213,6 +1213,23 @@
                             </ToolTipService.ToolTip>
                         </Border>
                     </Canvas>
+
+                    <Canvas x:Name="SelectionCanvas"
+                            Visibility="Visible">
+                        <!--
+                            LOAD BEARING Use Opacity instead of Visibility for these two FontIcons.
+                            Visibility::Collapsed prevents us from acquiring the desired size of the icons,
+                            resulting in an inability to scale them upon a FontSize change event
+                        -->
+                        <FontIcon x:Name="SelectionStartIcon"
+                                  FontFamily="Segoe MDL2 Assets"
+                                  Glyph="&#xE893;"
+                                  Opacity="0" />
+                        <FontIcon x:Name="SelectionEndIcon"
+                                  FontFamily="Segoe MDL2 Assets"
+                                  Glyph="&#xE892;"
+                                  Opacity="0" />
+                    </Canvas>
                 </SwapChainPanel>
 
                 <!--
diff --git a/src/cascadia/TerminalCore/Terminal.hpp b/src/cascadia/TerminalCore/Terminal.hpp
index a042ec360f3..6cbd3747453 100644
--- a/src/cascadia/TerminalCore/Terminal.hpp
+++ b/src/cascadia/TerminalCore/Terminal.hpp
@@ -248,6 +248,9 @@ class Microsoft::Terminal::Core::Terminal final :
 
     using UpdateSelectionParams = std::optional<std::pair<SelectionDirection, SelectionExpansion>>;
     UpdateSelectionParams ConvertKeyEventToUpdateSelectionParams(const ControlKeyStates mods, const WORD vkey) const;
+    bool MovingStart() const noexcept;
+    til::point SelectionStartForRendering() const;
+    til::point SelectionEndForRendering() const;
 
     const TextBuffer::TextAndColor RetrieveSelectedTextFromBuffer(bool trimTrailingWhitespace);
 #pragma endregion
diff --git a/src/cascadia/TerminalCore/TerminalSelection.cpp b/src/cascadia/TerminalCore/TerminalSelection.cpp
index 6d75d6d20c5..cddf90f17fe 100644
--- a/src/cascadia/TerminalCore/TerminalSelection.cpp
+++ b/src/cascadia/TerminalCore/TerminalSelection.cpp
@@ -82,6 +82,24 @@ const COORD Terminal::GetSelectionEnd() const noexcept
     return _selection->end;
 }
 
+til::point Terminal::SelectionStartForRendering() const
+{
+    auto pos{ _selection->start };
+    const auto bufferSize{ GetTextBuffer().GetSize() };
+    bufferSize.DecrementInBounds(pos);
+    pos.Y = base::ClampSub(pos.Y, _VisibleStartIndex());
+    return til::point{ pos };
+}
+
+til::point Terminal::SelectionEndForRendering() const
+{
+    auto pos{ _selection->end };
+    const auto bufferSize{ GetTextBuffer().GetSize() };
+    bufferSize.IncrementInBounds(pos);
+    pos.Y = base::ClampSub(pos.Y, _VisibleStartIndex());
+    return til::point{ pos };
+}
+
 // Method Description:
 // - Checks if selection is active
 // Return Value:
@@ -309,6 +327,13 @@ Terminal::UpdateSelectionParams Terminal::ConvertKeyEventToUpdateSelectionParams
     return std::nullopt;
 }
 
+bool Terminal::MovingStart() const noexcept
+{
+    // true --> we're moving start endpoint ("higher")
+    // false --> we're moving end endpoint ("lower")
+    return _selection->start == _selection->pivot ? false : true;
+}
+
 // Method Description:
 // - updates the selection endpoints based on a direction and expansion mode. Primarily used for keyboard selection.
 // Arguments:
@@ -318,10 +343,9 @@ Terminal::UpdateSelectionParams Terminal::ConvertKeyEventToUpdateSelectionParams
 void Terminal::UpdateSelection(SelectionDirection direction, SelectionExpansion mode, ControlKeyStates mods)
 {
     // 1. Figure out which endpoint to update
-    // If we're in mark mode, shift dictates whether you are moving the end or not.
-    // Otherwise, we're updating an existing selection, so one of the endpoints is the pivot,
-    //   signifying that the other endpoint is the one we want to move.
-    const auto movingEnd{ _markMode ? mods.IsShiftPressed() : _selection->start == _selection->pivot };
+    // One of the endpoints is the pivot,
+    // signifying that the other endpoint is the one we want to move.
+    const auto movingEnd{ _selection->start == _selection->pivot };
     auto targetPos{ movingEnd ? _selection->end : _selection->start };
 
     // 2. Perform the movement
@@ -346,12 +370,17 @@ void Terminal::UpdateSelection(SelectionDirection direction, SelectionExpansion
     if (_markMode)
     {
         // [Mark Mode]
-        // - moveSelectionEnd  --> just move end (i.e. shift + arrow keys)
-        // - !moveSelectionEnd --> move all three (i.e. just use arrow keys)
-        _selection->end = targetPos;
-        if (!movingEnd)
+        // - shift --> updating a standard selection
+        // - !shift --> move all three (i.e. just use arrow keys)
+        if (mods.IsShiftPressed())
+        {
+            auto targetStart = false;
+            std::tie(_selection->start, _selection->end) = _PivotSelection(targetPos, targetStart);
+        }
+        else
         {
             _selection->start = targetPos;
+            _selection->end = targetPos;
             _selection->pivot = targetPos;
         }
     }

From 214d3af27ff86cf9b4c3210a40e2cfc40cdecc94 Mon Sep 17 00:00:00 2001
From: Carlos Zamora <cazamor@microsoft.com>
Date: Thu, 2 Jun 2022 17:11:13 -0700
Subject: [PATCH 02/10] simplify logic a bit

---
 .../TerminalCore/TerminalSelection.cpp        | 23 ++++++-------------
 1 file changed, 7 insertions(+), 16 deletions(-)

diff --git a/src/cascadia/TerminalCore/TerminalSelection.cpp b/src/cascadia/TerminalCore/TerminalSelection.cpp
index cddf90f17fe..68b4a29b1e4 100644
--- a/src/cascadia/TerminalCore/TerminalSelection.cpp
+++ b/src/cascadia/TerminalCore/TerminalSelection.cpp
@@ -366,26 +366,17 @@ void Terminal::UpdateSelection(SelectionDirection direction, SelectionExpansion
     }
 
     // 3. Actually modify the selection
-    // NOTE: targetStart doesn't matter here
-    if (_markMode)
+    if (_markMode && !mods.IsShiftPressed())
     {
-        // [Mark Mode]
-        // - shift --> updating a standard selection
-        // - !shift --> move all three (i.e. just use arrow keys)
-        if (mods.IsShiftPressed())
-        {
-            auto targetStart = false;
-            std::tie(_selection->start, _selection->end) = _PivotSelection(targetPos, targetStart);
-        }
-        else
-        {
-            _selection->start = targetPos;
-            _selection->end = targetPos;
-            _selection->pivot = targetPos;
-        }
+        // [Mark Mode] + shift unpressed --> move all three (i.e. just use arrow keys)
+        _selection->start = targetPos;
+        _selection->end = targetPos;
+        _selection->pivot = targetPos;
     }
     else
     {
+        // [Mark Mode] + shift --> updating a standard selection
+        // NOTE: targetStart doesn't matter here
         auto targetStart = false;
         std::tie(_selection->start, _selection->end) = _PivotSelection(targetPos, targetStart);
     }

From f9baadc5514f18dccbfe32889ad06941020e90da Mon Sep 17 00:00:00 2001
From: Carlos Zamora <carlos.zamora@microsoft.com>
Date: Mon, 6 Jun 2022 14:25:34 -0700
Subject: [PATCH 03/10] add markers as paths; fix selectAll/toggleMarkMode

---
 src/cascadia/TerminalControl/ControlCore.cpp  |  2 +
 src/cascadia/TerminalControl/TermControl.cpp  | 45 ++++++++++---------
 src/cascadia/TerminalControl/TermControl.xaml | 19 +++-----
 src/cascadia/TerminalControl/pch.h            |  1 +
 4 files changed, 32 insertions(+), 35 deletions(-)

diff --git a/src/cascadia/TerminalControl/ControlCore.cpp b/src/cascadia/TerminalControl/ControlCore.cpp
index 5b538ce4755..4e501711a96 100644
--- a/src/cascadia/TerminalControl/ControlCore.cpp
+++ b/src/cascadia/TerminalControl/ControlCore.cpp
@@ -1037,6 +1037,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         auto lock = _terminal->LockForWriting();
         _terminal->SelectAll();
         _renderer->TriggerSelection();
+        _UpdateSelectionMarkersHandlers(*this, winrt::make<implementation::UpdateSelectionMarkersEventArgs>(false));
     }
 
     void ControlCore::ToggleMarkMode()
@@ -1044,6 +1045,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         auto lock = _terminal->LockForWriting();
         _terminal->ToggleMarkMode();
         _renderer->TriggerSelection();
+        _UpdateSelectionMarkersHandlers(*this, winrt::make<implementation::UpdateSelectionMarkersEventArgs>(false));
     }
 
     bool ControlCore::IsInMarkMode() const
diff --git a/src/cascadia/TerminalControl/TermControl.cpp b/src/cascadia/TerminalControl/TermControl.cpp
index da156b3c6ad..fbfad36c7cb 100644
--- a/src/cascadia/TerminalControl/TermControl.cpp
+++ b/src/cascadia/TerminalControl/TermControl.cpp
@@ -323,8 +323,8 @@ namespace winrt::Microsoft::Terminal::Control::implementation
 
         // Update selection markers
         Windows::UI::Xaml::Media::SolidColorBrush selectionBackgroundBrush{ til::color{ newAppearance.SelectionBackground() } };
-        SelectionStartIcon().Foreground(selectionBackgroundBrush);
-        SelectionEndIcon().Foreground(selectionBackgroundBrush);
+        SelectionStartMarker().Fill(selectionBackgroundBrush);
+        SelectionEndMarker().Fill(selectionBackgroundBrush);
 
         // Set TSF Foreground
         Media::SolidColorBrush foregroundBrush{};
@@ -2742,36 +2742,36 @@ namespace winrt::Microsoft::Terminal::Control::implementation
                 // figure out which endpoint to move, get it and the relevant icon (hide the other icon)
                 const auto movingStart{ _core.MovingStart() };
                 const auto selectionAnchor{ movingStart ? _core.SelectionAnchor() : _core.SelectionEnd() };
-                const auto& icon{ movingStart ? SelectionStartIcon() : SelectionEndIcon() };
-                const auto& otherIcon{ movingStart ? SelectionEndIcon() : SelectionStartIcon() };
+                const auto& marker{ movingStart ? SelectionStartMarker() : SelectionEndMarker() };
+                const auto& otherMarker{ movingStart ? SelectionEndMarker() : SelectionStartMarker() };
                 if (selectionAnchor.Y < 0 || selectionAnchor.Y >= _core.ViewHeight())
                 {
                     // if the endpoint is outside of the viewport,
                     // just hide the markers
-                    icon.Opacity(0);
-                    otherIcon.Opacity(0);
+                    marker.Visibility(Visibility::Collapsed);
+                    otherMarker.Visibility(Visibility::Collapsed);
                     co_return;
                 }
                 else
                 {
-                    icon.Opacity(1);
-                    otherIcon.Opacity(0);
+                    marker.Visibility(Visibility::Visible);
+                    otherMarker.Visibility(Visibility::Collapsed);
                 }
 
                 // Compute the location of the top left corner of the cell in DIPS
                 const til::point locationInDIPs{ _toPosInDips(selectionAnchor) };
 
-                // Move the icon to the top left corner of the cell
-                SelectionCanvas().SetLeft(icon,
+                // Move the marker to the top left corner of the cell
+                SelectionCanvas().SetLeft(marker,
                                           (locationInDIPs.x - SwapChainPanel().ActualOffset().x));
-                SelectionCanvas().SetTop(icon,
+                SelectionCanvas().SetTop(marker,
                                          (locationInDIPs.y - SwapChainPanel().ActualOffset().y));
             }
             else
             {
                 // hide selection markers
-                SelectionStartIcon().Opacity(0);
-                SelectionEndIcon().Opacity(0);
+                SelectionStartMarker().Visibility(Visibility::Collapsed);
+                SelectionEndMarker().Visibility(Visibility::Collapsed);
             }
         }
     }
@@ -2792,21 +2792,22 @@ namespace winrt::Microsoft::Terminal::Control::implementation
                                            const bool isInitialChange)
     {
         // scale the selection markers to be the size of a cell
-        auto scaleIconMarker = [fontWidth, fontHeight](Windows::UI::Xaml::Controls::FontIcon icon) {
-            const auto size{ icon.DesiredSize() };
-            const auto scaleX = fontWidth / size.Width;
-            const auto scaleY = fontHeight / size.Height;
+        auto scaleMarker = [fontWidth, fontHeight](Windows::UI::Xaml::Shapes::Path shape) {
+            // The selection markers were designed to be 5x14 in size,
+            // so use those dimensions below for the scaling
+            const auto scaleX = fontWidth / 5.0;
+            const auto scaleY = fontHeight / 14.0;
 
             Windows::UI::Xaml::Media::ScaleTransform transform{};
             transform.ScaleX(transform.ScaleX() * scaleX);
             transform.ScaleY(transform.ScaleY() * scaleY);
-            icon.RenderTransform(transform);
+            shape.RenderTransform(transform);
 
-            // now hide the icon
-            icon.Opacity(0);
+            // now hide the shape
+            shape.Visibility(Visibility::Collapsed);
         };
-        scaleIconMarker(SelectionStartIcon());
-        scaleIconMarker(SelectionEndIcon());
+        scaleMarker(SelectionStartMarker());
+        scaleMarker(SelectionEndMarker());
 
         // Don't try to inspect the core here. The Core is raising this while
         // it's holding its write lock. If the handlers calls back to some
diff --git a/src/cascadia/TerminalControl/TermControl.xaml b/src/cascadia/TerminalControl/TermControl.xaml
index 71f97be53b3..e5254b4bc72 100644
--- a/src/cascadia/TerminalControl/TermControl.xaml
+++ b/src/cascadia/TerminalControl/TermControl.xaml
@@ -1216,19 +1216,12 @@
 
                     <Canvas x:Name="SelectionCanvas"
                             Visibility="Visible">
-                        <!--
-                            LOAD BEARING Use Opacity instead of Visibility for these two FontIcons.
-                            Visibility::Collapsed prevents us from acquiring the desired size of the icons,
-                            resulting in an inability to scale them upon a FontSize change event
-                        -->
-                        <FontIcon x:Name="SelectionStartIcon"
-                                  FontFamily="Segoe MDL2 Assets"
-                                  Glyph="&#xE893;"
-                                  Opacity="0" />
-                        <FontIcon x:Name="SelectionEndIcon"
-                                  FontFamily="Segoe MDL2 Assets"
-                                  Glyph="&#xE892;"
-                                  Opacity="0" />
+                        <Path Name="SelectionStartMarker"
+                              Data="M 0 0 L 4 5.5996094 L 4 14 L 5 14 L 5 7 L 5 4.1992188 L 5 0 L 0 0 z "
+                              Visibility="Collapsed" />
+                        <Path Name="SelectionEndMarker"
+                              Data="M 0 0 L 0 4.1992188 L 0 7 L 0 14 L 1 14 L 1 5.5996094 L 5 0 L 0 0 z "
+                              Visibility="Collapsed" />
                     </Canvas>
                 </SwapChainPanel>
 
diff --git a/src/cascadia/TerminalControl/pch.h b/src/cascadia/TerminalControl/pch.h
index 7d710c5b5c7..34e10473509 100644
--- a/src/cascadia/TerminalControl/pch.h
+++ b/src/cascadia/TerminalControl/pch.h
@@ -47,6 +47,7 @@
 #include <winrt/Windows.ui.xaml.markup.h>
 #include <winrt/Windows.ApplicationModel.DataTransfer.h>
 #include <winrt/Windows.Storage.h>
+#include <winrt/Windows.UI.Xaml.Shapes.h>
 
 #include <winrt/Microsoft.Terminal.TerminalConnection.h>
 #include <winrt/Microsoft.Terminal.Core.h>

From aa2ff6b658f5f84d87d59b4dfce26b1412a71093 Mon Sep 17 00:00:00 2001
From: Carlos Zamora <carlos.zamora@microsoft.com>
Date: Tue, 7 Jun 2022 09:59:08 -0700
Subject: [PATCH 04/10] MovingStart-->MovingEnd

---
 src/cascadia/TerminalControl/ControlCore.cpp  | 10 ++++-
 src/cascadia/TerminalControl/ControlCore.h    |  3 +-
 src/cascadia/TerminalControl/ControlCore.idl  |  3 +-
 src/cascadia/TerminalControl/TermControl.cpp  | 43 +++++++++++++------
 src/cascadia/TerminalCore/Terminal.hpp        |  3 +-
 .../TerminalCore/TerminalSelection.cpp        | 18 +++++---
 6 files changed, 55 insertions(+), 25 deletions(-)

diff --git a/src/cascadia/TerminalControl/ControlCore.cpp b/src/cascadia/TerminalControl/ControlCore.cpp
index 4e501711a96..8073c38e94a 100644
--- a/src/cascadia/TerminalControl/ControlCore.cpp
+++ b/src/cascadia/TerminalControl/ControlCore.cpp
@@ -928,10 +928,16 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         return { end.X, end.Y };
     }
 
-    bool ControlCore::MovingStart() const
+    bool ControlCore::MovingEnd() const
     {
         auto lock = _terminal->LockForReading();
-        return _terminal->MovingStart();
+        return _terminal->MovingEnd();
+    }
+
+    bool ControlCore::MovingCursor() const
+    {
+        auto lock = _terminal->LockForReading();
+        return _terminal->MovingCursor();
     }
 
     // Method Description:
diff --git a/src/cascadia/TerminalControl/ControlCore.h b/src/cascadia/TerminalControl/ControlCore.h
index 59733bcb2f9..e79d4dbdd5d 100644
--- a/src/cascadia/TerminalControl/ControlCore.h
+++ b/src/cascadia/TerminalControl/ControlCore.h
@@ -153,7 +153,8 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         Windows::Foundation::Collections::IVector<winrt::hstring> SelectedText(bool trimTrailingWhitespace) const;
         Core::Point SelectionAnchor() const;
         Core::Point SelectionEnd() const;
-        bool MovingStart() const;
+        bool MovingEnd() const;
+        bool MovingCursor() const;
         void SetSelectionAnchor(const til::point& position);
         void SetEndSelectionPoint(const til::point& position);
 
diff --git a/src/cascadia/TerminalControl/ControlCore.idl b/src/cascadia/TerminalControl/ControlCore.idl
index e80ffdbe3da..77eca8873c5 100644
--- a/src/cascadia/TerminalControl/ControlCore.idl
+++ b/src/cascadia/TerminalControl/ControlCore.idl
@@ -92,7 +92,8 @@ namespace Microsoft.Terminal.Control
         IVector<String> SelectedText(Boolean trimTrailingWhitespace);
         Microsoft.Terminal.Core.Point SelectionAnchor { get; };
         Microsoft.Terminal.Core.Point SelectionEnd { get; };
-        Boolean MovingStart { get; };
+        Boolean MovingEnd { get; };
+        Boolean MovingCursor { get; };
 
         String HoveredUriText { get; };
         Windows.Foundation.IReference<Microsoft.Terminal.Core.Point> HoveredCell { get; };
diff --git a/src/cascadia/TerminalControl/TermControl.cpp b/src/cascadia/TerminalControl/TermControl.cpp
index fbfad36c7cb..a89f104a1bb 100644
--- a/src/cascadia/TerminalControl/TermControl.cpp
+++ b/src/cascadia/TerminalControl/TermControl.cpp
@@ -2738,12 +2738,28 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         {
             if (_core.HasSelection() && !args.ClearMarkers())
             {
+                // lambda helper function that can be used to display a selection marker
+                // - targetEnd: if true, target the "end" selection marker. Otherwise, target "start".
+                auto displayMarker = [&](bool targetEnd) {
+                    // Compute the location of the top left corner of the cell in DIPS
+                    const auto terminalPos{ targetEnd ? _core.SelectionEnd() : _core.SelectionAnchor() };
+                    const til::point locationInDIPs{ _toPosInDips(terminalPos) };
+
+                    // Move the marker to the top left corner of the cell
+                    const auto& marker{ targetEnd ? SelectionEndMarker() : SelectionStartMarker() };
+                    SelectionCanvas().SetLeft(marker,
+                                              (locationInDIPs.x - SwapChainPanel().ActualOffset().x));
+                    SelectionCanvas().SetTop(marker,
+                                             (locationInDIPs.y - SwapChainPanel().ActualOffset().y));
+                    marker.Visibility(Visibility::Visible);
+                };
+
                 // show/update selection markers
                 // figure out which endpoint to move, get it and the relevant icon (hide the other icon)
-                const auto movingStart{ _core.MovingStart() };
-                const auto selectionAnchor{ movingStart ? _core.SelectionAnchor() : _core.SelectionEnd() };
-                const auto& marker{ movingStart ? SelectionStartMarker() : SelectionEndMarker() };
-                const auto& otherMarker{ movingStart ? SelectionEndMarker() : SelectionStartMarker() };
+                const auto movingEnd{ _core.MovingEnd() };
+                const auto selectionAnchor{ movingEnd ? _core.SelectionEnd() : _core.SelectionAnchor() };
+                const auto& marker{ movingEnd ? SelectionEndMarker() : SelectionStartMarker() };
+                const auto& otherMarker{ movingEnd ? SelectionStartMarker() : SelectionEndMarker() };
                 if (selectionAnchor.Y < 0 || selectionAnchor.Y >= _core.ViewHeight())
                 {
                     // if the endpoint is outside of the viewport,
@@ -2752,20 +2768,19 @@ namespace winrt::Microsoft::Terminal::Control::implementation
                     otherMarker.Visibility(Visibility::Collapsed);
                     co_return;
                 }
+                else if (_core.MovingCursor())
+                {
+                    // display both markers
+                    displayMarker(true);
+                    displayMarker(false);
+                }
                 else
                 {
-                    marker.Visibility(Visibility::Visible);
+                    // display one marker,
+                    // but hide the other
+                    displayMarker(movingEnd);
                     otherMarker.Visibility(Visibility::Collapsed);
                 }
-
-                // Compute the location of the top left corner of the cell in DIPS
-                const til::point locationInDIPs{ _toPosInDips(selectionAnchor) };
-
-                // Move the marker to the top left corner of the cell
-                SelectionCanvas().SetLeft(marker,
-                                          (locationInDIPs.x - SwapChainPanel().ActualOffset().x));
-                SelectionCanvas().SetTop(marker,
-                                         (locationInDIPs.y - SwapChainPanel().ActualOffset().y));
             }
             else
             {
diff --git a/src/cascadia/TerminalCore/Terminal.hpp b/src/cascadia/TerminalCore/Terminal.hpp
index 6cbd3747453..2ce3e9064a5 100644
--- a/src/cascadia/TerminalCore/Terminal.hpp
+++ b/src/cascadia/TerminalCore/Terminal.hpp
@@ -248,7 +248,8 @@ class Microsoft::Terminal::Core::Terminal final :
 
     using UpdateSelectionParams = std::optional<std::pair<SelectionDirection, SelectionExpansion>>;
     UpdateSelectionParams ConvertKeyEventToUpdateSelectionParams(const ControlKeyStates mods, const WORD vkey) const;
-    bool MovingStart() const noexcept;
+    bool MovingEnd() const noexcept;
+    bool MovingCursor() const noexcept;
     til::point SelectionStartForRendering() const;
     til::point SelectionEndForRendering() const;
 
diff --git a/src/cascadia/TerminalCore/TerminalSelection.cpp b/src/cascadia/TerminalCore/TerminalSelection.cpp
index 68b4a29b1e4..6748997d28d 100644
--- a/src/cascadia/TerminalCore/TerminalSelection.cpp
+++ b/src/cascadia/TerminalCore/TerminalSelection.cpp
@@ -327,11 +327,18 @@ Terminal::UpdateSelectionParams Terminal::ConvertKeyEventToUpdateSelectionParams
     return std::nullopt;
 }
 
-bool Terminal::MovingStart() const noexcept
+bool Terminal::MovingEnd() const noexcept
 {
-    // true --> we're moving start endpoint ("higher")
-    // false --> we're moving end endpoint ("lower")
-    return _selection->start == _selection->pivot ? false : true;
+    // true --> we're moving end endpoint ("lower")
+    // false --> we're moving start endpoint ("higher")
+    return _selection->start == _selection->pivot;
+}
+
+bool Terminal::MovingCursor() const noexcept
+{
+    // true --> we're moving end endpoint ("lower")
+    // false --> we're moving start endpoint ("higher")
+    return _selection->start == _selection->pivot && _selection->pivot == _selection->end;
 }
 
 // Method Description:
@@ -345,8 +352,7 @@ void Terminal::UpdateSelection(SelectionDirection direction, SelectionExpansion
     // 1. Figure out which endpoint to update
     // One of the endpoints is the pivot,
     // signifying that the other endpoint is the one we want to move.
-    const auto movingEnd{ _selection->start == _selection->pivot };
-    auto targetPos{ movingEnd ? _selection->end : _selection->start };
+    auto targetPos{ MovingEnd() ? _selection->end : _selection->start };
 
     // 2. Perform the movement
     switch (mode)

From b6a11540fd67fbe87d8869b3ee7db997d674fc21 Mon Sep 17 00:00:00 2001
From: Carlos Zamora <carlos.zamora@microsoft.com>
Date: Thu, 9 Jun 2022 16:12:16 -0700
Subject: [PATCH 05/10] address zadji's feedback

---
 src/cascadia/TerminalControl/ControlCore.cpp | 33 +++++++++-----------
 src/cascadia/TerminalControl/ControlCore.h   |  1 +
 src/cascadia/TerminalControl/EventArgs.h     |  1 -
 src/cascadia/TerminalControl/TermControl.cpp |  6 ++--
 4 files changed, 19 insertions(+), 22 deletions(-)

diff --git a/src/cascadia/TerminalControl/ControlCore.cpp b/src/cascadia/TerminalControl/ControlCore.cpp
index eedecc89785..241c10844da 100644
--- a/src/cascadia/TerminalControl/ControlCore.cpp
+++ b/src/cascadia/TerminalControl/ControlCore.cpp
@@ -399,7 +399,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
             {
                 auto lock = _terminal->LockForWriting();
                 _terminal->SelectAll();
-                _renderer->TriggerSelection();
+                _updateSelection(false);
                 return true;
             }
 
@@ -408,8 +408,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
             {
                 auto lock = _terminal->LockForWriting();
                 _terminal->UpdateSelection(updateSlnParams->first, updateSlnParams->second, modifiers);
-                _renderer->TriggerSelection();
-                _UpdateSelectionMarkersHandlers(*this, winrt::make<implementation::UpdateSelectionMarkersEventArgs>(false));
+                _updateSelection(false);
                 return true;
             }
 
@@ -417,8 +416,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
             if (!modifiers.IsWinPressed())
             {
                 _terminal->ClearSelection();
-                _renderer->TriggerSelection();
-                _UpdateSelectionMarkersHandlers(*this, winrt::make<implementation::UpdateSelectionMarkersEventArgs>(true));
+                _updateSelection(true);
             }
 
             // When there is a selection active, escape should clear it and NOT flow through
@@ -962,8 +960,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
 
         // save location (for rendering) + render
         _terminal->SetSelectionEnd(terminalPosition);
-        _renderer->TriggerSelection();
-        _UpdateSelectionMarkersHandlers(*this, winrt::make<implementation::UpdateSelectionMarkersEventArgs>(true));
+        _updateSelection(true);
     }
 
     // Called when the Terminal wants to set something to the clipboard, i.e.
@@ -1025,8 +1022,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         if (!_settings->CopyOnSelect())
         {
             _terminal->ClearSelection();
-            _renderer->TriggerSelection();
-            _UpdateSelectionMarkersHandlers(*this, winrt::make<implementation::UpdateSelectionMarkersEventArgs>(true));
+            _updateSelection(true);
         }
 
         // send data up for clipboard
@@ -1042,8 +1038,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
     {
         auto lock = _terminal->LockForWriting();
         _terminal->SelectAll();
-        _renderer->TriggerSelection();
-        _UpdateSelectionMarkersHandlers(*this, winrt::make<implementation::UpdateSelectionMarkersEventArgs>(false));
+        _updateSelection(false);
     }
 
     bool ControlCore::ToggleBlockSelection()
@@ -1052,7 +1047,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         if (_terminal->IsSelectionActive())
         {
             _terminal->SetBlockSelection(!_terminal->IsBlockSelection());
-            _renderer->TriggerSelection();
+            _updateSelection(false);
             return true;
         }
         return false;
@@ -1062,8 +1057,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
     {
         auto lock = _terminal->LockForWriting();
         _terminal->ToggleMarkMode();
-        _renderer->TriggerSelection();
-        _UpdateSelectionMarkersHandlers(*this, winrt::make<implementation::UpdateSelectionMarkersEventArgs>(false));
+        _updateSelection(false);
     }
 
     bool ControlCore::IsInMarkMode() const
@@ -1078,7 +1072,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
     {
         _terminal->WritePastedText(hstr);
         _terminal->ClearSelection();
-        _renderer->TriggerSelection();
+        _updateSelection(true);
         _terminal->TrySnapOnInput();
     }
 
@@ -1394,8 +1388,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         {
             _terminal->SetBlockSelection(false);
             search.Select();
-            _renderer->TriggerSelection();
-            _UpdateSelectionMarkersHandlers(*this, winrt::make<implementation::UpdateSelectionMarkersEventArgs>(true));
+            _updateSelection(true);
         }
 
         // Raise a FoundMatch event, which the control will use to notify
@@ -1596,9 +1589,13 @@ namespace winrt::Microsoft::Terminal::Control::implementation
             _terminal->MultiClickSelection(terminalPosition, mode);
             selectionNeedsToBeCopied = true;
         }
+        _updateSelection(true);
+    }
 
+    void ControlCore::_updateSelection(const bool clearMarkers)
+    {
         _renderer->TriggerSelection();
-        _UpdateSelectionMarkersHandlers(*this, winrt::make<implementation::UpdateSelectionMarkersEventArgs>(true));
+        _UpdateSelectionMarkersHandlers(*this, winrt::make<implementation::UpdateSelectionMarkersEventArgs>(clearMarkers));
     }
 
     void ControlCore::AttachUiaEngine(::Microsoft::Console::Render::IRenderEngine* const pEngine)
diff --git a/src/cascadia/TerminalControl/ControlCore.h b/src/cascadia/TerminalControl/ControlCore.h
index e896c33b56f..d741d74148f 100644
--- a/src/cascadia/TerminalControl/ControlCore.h
+++ b/src/cascadia/TerminalControl/ControlCore.h
@@ -267,6 +267,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         bool _setFontSizeUnderLock(int fontSize);
         void _updateFont(const bool initialUpdate = false);
         void _refreshSizeUnderLock();
+        void _updateSelection(const bool clearMarkers);
 
         void _sendInputToConnection(std::wstring_view wstr);
 
diff --git a/src/cascadia/TerminalControl/EventArgs.h b/src/cascadia/TerminalControl/EventArgs.h
index edefb2b0045..a542e391f63 100644
--- a/src/cascadia/TerminalControl/EventArgs.h
+++ b/src/cascadia/TerminalControl/EventArgs.h
@@ -14,7 +14,6 @@
 #include "FoundResultsArgs.g.h"
 #include "ShowWindowArgs.g.h"
 #include "UpdateSelectionMarkersEventArgs.g.h"
-#include "cppwinrt_utils.h" // TODO CARLOS: maybe we can remove this include?
 
 namespace winrt::Microsoft::Terminal::Control::implementation
 {
diff --git a/src/cascadia/TerminalControl/TermControl.cpp b/src/cascadia/TerminalControl/TermControl.cpp
index 81642a7dc92..dae4397c20f 100644
--- a/src/cascadia/TerminalControl/TermControl.cpp
+++ b/src/cascadia/TerminalControl/TermControl.cpp
@@ -2818,9 +2818,9 @@ namespace winrt::Microsoft::Terminal::Control::implementation
             const auto scaleX = fontWidth / 5.0;
             const auto scaleY = fontHeight / 14.0;
 
-            Windows::UI::Xaml::Media::ScaleTransform transform{};
-            transform.ScaleX(transform.ScaleX() * scaleX);
-            transform.ScaleY(transform.ScaleY() * scaleY);
+            Windows::UI::Xaml::Media::ScaleTransform transform;
+            transform.ScaleX(scaleX);
+            transform.ScaleY(scaleY);
             shape.RenderTransform(transform);
 
             // now hide the shape

From 659230a34a2707ecd34c0be1950f9776acc20356 Mon Sep 17 00:00:00 2001
From: Carlos Zamora <cazamor@microsoft.com>
Date: Tue, 14 Jun 2022 17:06:13 -0700
Subject: [PATCH 06/10] address Dustin's feedback

---
 src/cascadia/TerminalControl/ControlCore.cpp  | 73 +++++++++++--------
 src/cascadia/TerminalControl/ControlCore.h    |  7 +-
 src/cascadia/TerminalControl/ControlCore.idl  | 15 +++-
 src/cascadia/TerminalControl/TermControl.cpp  | 37 +++++++---
 .../TerminalCore/TerminalSelection.cpp        | 11 ++-
 5 files changed, 90 insertions(+), 53 deletions(-)

diff --git a/src/cascadia/TerminalControl/ControlCore.cpp b/src/cascadia/TerminalControl/ControlCore.cpp
index 0ca8383af4e..629702142b2 100644
--- a/src/cascadia/TerminalControl/ControlCore.cpp
+++ b/src/cascadia/TerminalControl/ControlCore.cpp
@@ -421,7 +421,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
             {
                 auto lock = _terminal->LockForWriting();
                 _terminal->SelectAll();
-                _updateSelection(false);
+                _updateSelection();
                 return true;
             }
 
@@ -430,7 +430,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
             {
                 auto lock = _terminal->LockForWriting();
                 _terminal->UpdateSelection(updateSlnParams->first, updateSlnParams->second, modifiers);
-                _updateSelection(false);
+                _updateSelection();
                 return true;
             }
 
@@ -438,7 +438,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
             if (!modifiers.IsWinPressed())
             {
                 _terminal->ClearSelection();
-                _updateSelection(true);
+                _updateSelection();
             }
 
             // When there is a selection active, escape should clear it and NOT flow through
@@ -934,30 +934,29 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         _terminal->SetSelectionAnchor(position);
     }
 
-    Core::Point ControlCore::SelectionAnchor() const
+    // Method Description:
+    // - Retrieves selection metadata from Terminal necessary to draw the
+    //    selection markers.
+    // - Since all of this needs to be done under lock, it is more performant
+    //    to throw it all in a struct and pass it along.
+    Control::SelectionMarkerMetadata ControlCore::SelectionMarkerInfo() const
     {
         auto lock = _terminal->LockForReading();
-        const auto start = _terminal->SelectionStartForRendering();
-        return { start.X, start.Y };
-    }
+        Control::SelectionMarkerMetadata info;
 
-    Core::Point ControlCore::SelectionEnd() const
-    {
-        auto lock = _terminal->LockForReading();
-        const auto end = _terminal->SelectionEndForRendering();
-        return { end.X, end.Y };
-    }
+        const auto start{ _terminal->SelectionStartForRendering() };
+        info.StartPos = { start.X, start.Y };
 
-    bool ControlCore::MovingEnd() const
-    {
-        auto lock = _terminal->LockForReading();
-        return _terminal->MovingEnd();
-    }
+        const auto end{ _terminal->SelectionEndForRendering() };
+        info.EndPos = { end.X, end.Y };
 
-    bool ControlCore::MovingCursor() const
-    {
-        auto lock = _terminal->LockForReading();
-        return _terminal->MovingCursor();
+        info.MovingEnd = _terminal->MovingEnd();
+        info.MovingCursor = _terminal->MovingCursor();
+
+        const auto bufferSize{ _terminal->GetTextBuffer().GetSize() };
+        info.FlipStartMarker = _terminal->GetSelectionAnchor() == bufferSize.Origin();
+        info.FlipEndMarker = _terminal->GetSelectionEnd() == bufferSize.BottomRightInclusive();
+        return info;
     }
 
     // Method Description:
@@ -982,7 +981,11 @@ namespace winrt::Microsoft::Terminal::Control::implementation
 
         // save location (for rendering) + render
         _terminal->SetSelectionEnd(terminalPosition);
-        _updateSelection(true);
+        _renderer->TriggerSelection();
+
+        // this is used for mouse dragging,
+        // so hide the markers
+        _UpdateSelectionMarkersHandlers(*this, winrt::make<implementation::UpdateSelectionMarkersEventArgs>(true));
     }
 
     // Called when the Terminal wants to set something to the clipboard, i.e.
@@ -1044,7 +1047,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         if (!_settings->CopyOnSelect())
         {
             _terminal->ClearSelection();
-            _updateSelection(true);
+            _updateSelection();
         }
 
         // send data up for clipboard
@@ -1060,7 +1063,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
     {
         auto lock = _terminal->LockForWriting();
         _terminal->SelectAll();
-        _updateSelection(false);
+        _updateSelection();
     }
 
     bool ControlCore::ToggleBlockSelection()
@@ -1069,7 +1072,10 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         if (_terminal->IsSelectionActive())
         {
             _terminal->SetBlockSelection(!_terminal->IsBlockSelection());
-            _updateSelection(false);
+            _renderer->TriggerSelection();
+            // do not update the selection markers!
+            // if we were showing them, keep it that way.
+            // otherwise, continue to not show them
             return true;
         }
         return false;
@@ -1079,7 +1085,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
     {
         auto lock = _terminal->LockForWriting();
         _terminal->ToggleMarkMode();
-        _updateSelection(false);
+        _updateSelection();
     }
 
     bool ControlCore::IsInMarkMode() const
@@ -1094,7 +1100,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
     {
         _terminal->WritePastedText(hstr);
         _terminal->ClearSelection();
-        _updateSelection(true);
+        _updateSelection();
         _terminal->TrySnapOnInput();
     }
 
@@ -1414,7 +1420,11 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         {
             _terminal->SetBlockSelection(false);
             search.Select();
-            _updateSelection(true);
+            _renderer->TriggerSelection();
+
+            // this is used for search,
+            // so hide the markers
+            _UpdateSelectionMarkersHandlers(*this, winrt::make<implementation::UpdateSelectionMarkersEventArgs>(true));
         }
 
         // Raise a FoundMatch event, which the control will use to notify
@@ -1615,12 +1625,13 @@ namespace winrt::Microsoft::Terminal::Control::implementation
             _terminal->MultiClickSelection(terminalPosition, mode);
             selectionNeedsToBeCopied = true;
         }
-        _updateSelection(true);
+        _updateSelection();
     }
 
-    void ControlCore::_updateSelection(const bool clearMarkers)
+    void ControlCore::_updateSelection()
     {
         _renderer->TriggerSelection();
+        const bool clearMarkers{ !_terminal->IsSelectionActive() };
         _UpdateSelectionMarkersHandlers(*this, winrt::make<implementation::UpdateSelectionMarkersEventArgs>(clearMarkers));
     }
 
diff --git a/src/cascadia/TerminalControl/ControlCore.h b/src/cascadia/TerminalControl/ControlCore.h
index 26e0daf2bea..b4017b08806 100644
--- a/src/cascadia/TerminalControl/ControlCore.h
+++ b/src/cascadia/TerminalControl/ControlCore.h
@@ -159,10 +159,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         bool HasSelection() const;
         bool CopyOnSelect() const;
         Windows::Foundation::Collections::IVector<winrt::hstring> SelectedText(bool trimTrailingWhitespace) const;
-        Core::Point SelectionAnchor() const;
-        Core::Point SelectionEnd() const;
-        bool MovingEnd() const;
-        bool MovingCursor() const;
+        Control::SelectionMarkerMetadata SelectionMarkerInfo() const;
         void SetSelectionAnchor(const til::point position);
         void SetEndSelectionPoint(const til::point position);
 
@@ -274,7 +271,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         bool _setFontSizeUnderLock(int fontSize);
         void _updateFont(const bool initialUpdate = false);
         void _refreshSizeUnderLock();
-        void _updateSelection(const bool clearMarkers);
+        void _updateSelection();
 
         void _sendInputToConnection(std::wstring_view wstr);
 
diff --git a/src/cascadia/TerminalControl/ControlCore.idl b/src/cascadia/TerminalControl/ControlCore.idl
index 2015b099eb3..82bd902c52c 100644
--- a/src/cascadia/TerminalControl/ControlCore.idl
+++ b/src/cascadia/TerminalControl/ControlCore.idl
@@ -29,6 +29,16 @@ namespace Microsoft.Terminal.Control
         All
     };
 
+    struct SelectionMarkerMetadata
+    {
+        Microsoft.Terminal.Core.Point StartPos;
+        Microsoft.Terminal.Core.Point EndPos;
+        Boolean MovingEnd;
+        Boolean MovingCursor;
+        Boolean FlipStartMarker;
+        Boolean FlipEndMarker;
+    };
+
     [default_interface] runtimeclass ControlCore : ICoreState
     {
         ControlCore(IControlSettings settings,
@@ -90,10 +100,7 @@ namespace Microsoft.Terminal.Control
 
         Boolean HasSelection { get; };
         IVector<String> SelectedText(Boolean trimTrailingWhitespace);
-        Microsoft.Terminal.Core.Point SelectionAnchor { get; };
-        Microsoft.Terminal.Core.Point SelectionEnd { get; };
-        Boolean MovingEnd { get; };
-        Boolean MovingCursor { get; };
+        SelectionMarkerMetadata SelectionMarkerInfo { get; };
 
         String HoveredUriText { get; };
         Windows.Foundation.IReference<Microsoft.Terminal.Core.Point> HoveredCell { get; };
diff --git a/src/cascadia/TerminalControl/TermControl.cpp b/src/cascadia/TerminalControl/TermControl.cpp
index 5eb9e8824e8..2e0bfe41542 100644
--- a/src/cascadia/TerminalControl/TermControl.cpp
+++ b/src/cascadia/TerminalControl/TermControl.cpp
@@ -2788,15 +2788,31 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         {
             if (_core.HasSelection() && !args.ClearMarkers())
             {
+                // retrieve all of the necessary selection marker data
+                // from the TerminalCore layer under one lock to improve performance
+                const auto markerData{ _core.SelectionMarkerInfo() };
+
                 // lambda helper function that can be used to display a selection marker
                 // - targetEnd: if true, target the "end" selection marker. Otherwise, target "start".
                 auto displayMarker = [&](bool targetEnd) {
+                    const auto flipMarker{ targetEnd ? markerData.FlipEndMarker : markerData.FlipStartMarker };
+                    const auto& marker{ targetEnd ? SelectionEndMarker() : SelectionStartMarker() };
+
+                    // Ensure the marker is oriented properly
+                    // (i.e. if start is at the beginning of the buffer, it should be flipped)
+                    auto transform{ marker.RenderTransform().as<Windows::UI::Xaml::Media::ScaleTransform>() };
+                    transform.ScaleX(std::abs(transform.ScaleX()) * (flipMarker ? -1.0 : 1.0));
+                    marker.RenderTransform(transform);
+
                     // Compute the location of the top left corner of the cell in DIPS
-                    const auto terminalPos{ targetEnd ? _core.SelectionEnd() : _core.SelectionAnchor() };
+                    auto terminalPos{ targetEnd ? markerData.EndPos : markerData.StartPos };
+                    if (flipMarker)
+                    {
+                        terminalPos.X += targetEnd ? -1 : 1;
+                    }
                     const til::point locationInDIPs{ _toPosInDips(terminalPos) };
 
                     // Move the marker to the top left corner of the cell
-                    const auto& marker{ targetEnd ? SelectionEndMarker() : SelectionStartMarker() };
                     SelectionCanvas().SetLeft(marker,
                                               (locationInDIPs.x - SwapChainPanel().ActualOffset().x));
                     SelectionCanvas().SetTop(marker,
@@ -2806,10 +2822,9 @@ namespace winrt::Microsoft::Terminal::Control::implementation
 
                 // show/update selection markers
                 // figure out which endpoint to move, get it and the relevant icon (hide the other icon)
-                const auto movingEnd{ _core.MovingEnd() };
-                const auto selectionAnchor{ movingEnd ? _core.SelectionEnd() : _core.SelectionAnchor() };
-                const auto& marker{ movingEnd ? SelectionEndMarker() : SelectionStartMarker() };
-                const auto& otherMarker{ movingEnd ? SelectionStartMarker() : SelectionEndMarker() };
+                const auto selectionAnchor{ markerData.MovingEnd ? markerData.EndPos : markerData.StartPos };
+                const auto& marker{ markerData.MovingEnd ? SelectionEndMarker() : SelectionStartMarker() };
+                const auto& otherMarker{ markerData.MovingEnd ? SelectionStartMarker() : SelectionEndMarker() };
                 if (selectionAnchor.Y < 0 || selectionAnchor.Y >= _core.ViewHeight())
                 {
                     // if the endpoint is outside of the viewport,
@@ -2818,7 +2833,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
                     otherMarker.Visibility(Visibility::Collapsed);
                     co_return;
                 }
-                else if (_core.MovingCursor())
+                else if (markerData.MovingCursor)
                 {
                     // display both markers
                     displayMarker(true);
@@ -2828,7 +2843,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
                 {
                     // display one marker,
                     // but hide the other
-                    displayMarker(movingEnd);
+                    displayMarker(markerData.MovingEnd);
                     otherMarker.Visibility(Visibility::Collapsed);
                 }
             }
@@ -2857,11 +2872,11 @@ namespace winrt::Microsoft::Terminal::Control::implementation
                                            const bool isInitialChange)
     {
         // scale the selection markers to be the size of a cell
-        auto scaleMarker = [fontWidth, fontHeight](Windows::UI::Xaml::Shapes::Path shape) {
+        auto scaleMarker = [fontWidth, fontHeight, dpiScale{ SwapChainPanel().CompositionScaleX() }](const Windows::UI::Xaml::Shapes::Path& shape) {
             // The selection markers were designed to be 5x14 in size,
             // so use those dimensions below for the scaling
-            const auto scaleX = fontWidth / 5.0;
-            const auto scaleY = fontHeight / 14.0;
+            const auto scaleX = fontWidth / 5.0 / dpiScale;
+            const auto scaleY = fontHeight / 14.0 / dpiScale;
 
             Windows::UI::Xaml::Media::ScaleTransform transform;
             transform.ScaleX(scaleX);
diff --git a/src/cascadia/TerminalCore/TerminalSelection.cpp b/src/cascadia/TerminalCore/TerminalSelection.cpp
index c77f3f7b8f1..22ff09ee564 100644
--- a/src/cascadia/TerminalCore/TerminalSelection.cpp
+++ b/src/cascadia/TerminalCore/TerminalSelection.cpp
@@ -82,6 +82,9 @@ const til::point Terminal::GetSelectionEnd() const noexcept
     return _selection->end;
 }
 
+// Method Description:
+// - Gets the viewport-relative position of where to draw the marker
+//    for the selection's start endpoint
 til::point Terminal::SelectionStartForRendering() const
 {
     auto pos{ _selection->start };
@@ -91,6 +94,9 @@ til::point Terminal::SelectionStartForRendering() const
     return til::point{ pos };
 }
 
+// Method Description:
+// - Gets the viewport-relative position of where to draw the marker
+//    for the selection's end endpoint
 til::point Terminal::SelectionEndForRendering() const
 {
     auto pos{ _selection->end };
@@ -337,8 +343,9 @@ bool Terminal::MovingEnd() const noexcept
 
 bool Terminal::MovingCursor() const noexcept
 {
-    // true --> we're moving end endpoint ("lower")
-    // false --> we're moving start endpoint ("higher")
+    // Relevant for keyboard selection:
+    // true --> the selection is just a "cursor"; we're moving everything together with arrow keys
+    // false --> otherwise
     return _selection->start == _selection->pivot && _selection->pivot == _selection->end;
 }
 

From 2007e180fdea24d220758258a095b18e3ed07c19 Mon Sep 17 00:00:00 2001
From: Carlos Zamora <cazamor@microsoft.com>
Date: Wed, 15 Jun 2022 14:24:33 -0700
Subject: [PATCH 07/10] flip markers at side boundaries

---
 src/cascadia/TerminalControl/ControlCore.cpp   |  4 ++--
 src/cascadia/TerminalControl/TermControl.cpp   |  4 +++-
 .../TerminalCore/TerminalSelection.cpp         | 18 ++++++++++++++++--
 3 files changed, 21 insertions(+), 5 deletions(-)

diff --git a/src/cascadia/TerminalControl/ControlCore.cpp b/src/cascadia/TerminalControl/ControlCore.cpp
index 629702142b2..b81800592fc 100644
--- a/src/cascadia/TerminalControl/ControlCore.cpp
+++ b/src/cascadia/TerminalControl/ControlCore.cpp
@@ -954,8 +954,8 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         info.MovingCursor = _terminal->MovingCursor();
 
         const auto bufferSize{ _terminal->GetTextBuffer().GetSize() };
-        info.FlipStartMarker = _terminal->GetSelectionAnchor() == bufferSize.Origin();
-        info.FlipEndMarker = _terminal->GetSelectionEnd() == bufferSize.BottomRightInclusive();
+        info.FlipStartMarker = _terminal->GetSelectionAnchor().x == bufferSize.Left();
+        info.FlipEndMarker = _terminal->GetSelectionEnd().x == bufferSize.RightInclusive();
         return info;
     }
 
diff --git a/src/cascadia/TerminalControl/TermControl.cpp b/src/cascadia/TerminalControl/TermControl.cpp
index 2e0bfe41542..01209c683b9 100644
--- a/src/cascadia/TerminalControl/TermControl.cpp
+++ b/src/cascadia/TerminalControl/TermControl.cpp
@@ -2808,7 +2808,9 @@ namespace winrt::Microsoft::Terminal::Control::implementation
                     auto terminalPos{ targetEnd ? markerData.EndPos : markerData.StartPos };
                     if (flipMarker)
                     {
-                        terminalPos.X += targetEnd ? -1 : 1;
+                        // When we flip the marker, a negative scaling makes us be one cell-width to the left.
+                        // Add one to the viewport pos' x-coord to fix that.
+                        terminalPos.X += 1;
                     }
                     const til::point locationInDIPs{ _toPosInDips(terminalPos) };
 
diff --git a/src/cascadia/TerminalCore/TerminalSelection.cpp b/src/cascadia/TerminalCore/TerminalSelection.cpp
index 22ff09ee564..98729c789b1 100644
--- a/src/cascadia/TerminalCore/TerminalSelection.cpp
+++ b/src/cascadia/TerminalCore/TerminalSelection.cpp
@@ -89,7 +89,14 @@ til::point Terminal::SelectionStartForRendering() const
 {
     auto pos{ _selection->start };
     const auto bufferSize{ GetTextBuffer().GetSize() };
-    bufferSize.DecrementInBounds(pos);
+    if (pos.x != bufferSize.Left())
+    {
+        // In general, we need to draw the marker one before the
+        // beginning of the selection.
+        // When we're at the left boundary, we want to
+        // flip the marker, so we skip this step.
+        bufferSize.DecrementInBounds(pos);
+    }
     pos.Y = base::ClampSub(pos.Y, _VisibleStartIndex());
     return til::point{ pos };
 }
@@ -101,7 +108,14 @@ til::point Terminal::SelectionEndForRendering() const
 {
     auto pos{ _selection->end };
     const auto bufferSize{ GetTextBuffer().GetSize() };
-    bufferSize.IncrementInBounds(pos);
+    if (pos.x != bufferSize.RightInclusive())
+    {
+        // In general, we need to draw the marker one after the
+        // end of the selection.
+        // When we're at the right boundary, we want to
+        // flip the marker, so we skip this step.
+        bufferSize.IncrementInBounds(pos);
+    }
     pos.Y = base::ClampSub(pos.Y, _VisibleStartIndex());
     return til::point{ pos };
 }

From 4623371334591a89826628cd41212ba3a91906c2 Mon Sep 17 00:00:00 2001
From: Carlos Zamora <cazamor@microsoft.com>
Date: Thu, 16 Jun 2022 13:40:09 -0700
Subject: [PATCH 08/10] fix unfocused appearance bug

---
 src/cascadia/TerminalControl/TermControl.cpp | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/cascadia/TerminalControl/TermControl.cpp b/src/cascadia/TerminalControl/TermControl.cpp
index 01209c683b9..2ca6a972781 100644
--- a/src/cascadia/TerminalControl/TermControl.cpp
+++ b/src/cascadia/TerminalControl/TermControl.cpp
@@ -1837,7 +1837,13 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         update.newValue = args.ViewTop();
 
         _updateScrollBar->Run(update);
-        _updateSelectionMarkers(nullptr, winrt::make<UpdateSelectionMarkersEventArgs>(false));
+
+        // if a selection marker is already visible,
+        // update the position of those markers
+        if (SelectionStartMarker().Visibility() == Visibility::Visible || SelectionEndMarker().Visibility() == Visibility::Visible)
+        {
+            _updateSelectionMarkers(nullptr, winrt::make<UpdateSelectionMarkersEventArgs>(false));
+        }
     }
 
     // Method Description:

From 5eb17173c26551937a12573e22ef2846912e8409 Mon Sep 17 00:00:00 2001
From: Carlos Zamora <cazamor@microsoft.com>
Date: Fri, 17 Jun 2022 11:28:36 -0700
Subject: [PATCH 09/10] update names for marker data

---
 src/cascadia/TerminalControl/ControlCore.cpp | 8 ++++----
 src/cascadia/TerminalControl/ControlCore.h   | 2 +-
 src/cascadia/TerminalControl/ControlCore.idl | 8 ++++----
 src/cascadia/TerminalControl/TermControl.cpp | 4 ++--
 4 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/src/cascadia/TerminalControl/ControlCore.cpp b/src/cascadia/TerminalControl/ControlCore.cpp
index b81800592fc..1e60af76d3b 100644
--- a/src/cascadia/TerminalControl/ControlCore.cpp
+++ b/src/cascadia/TerminalControl/ControlCore.cpp
@@ -939,10 +939,10 @@ namespace winrt::Microsoft::Terminal::Control::implementation
     //    selection markers.
     // - Since all of this needs to be done under lock, it is more performant
     //    to throw it all in a struct and pass it along.
-    Control::SelectionMarkerMetadata ControlCore::SelectionMarkerInfo() const
+    Control::SelectionData ControlCore::SelectionInfo() const
     {
         auto lock = _terminal->LockForReading();
-        Control::SelectionMarkerMetadata info;
+        Control::SelectionData info;
 
         const auto start{ _terminal->SelectionStartForRendering() };
         info.StartPos = { start.X, start.Y };
@@ -954,8 +954,8 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         info.MovingCursor = _terminal->MovingCursor();
 
         const auto bufferSize{ _terminal->GetTextBuffer().GetSize() };
-        info.FlipStartMarker = _terminal->GetSelectionAnchor().x == bufferSize.Left();
-        info.FlipEndMarker = _terminal->GetSelectionEnd().x == bufferSize.RightInclusive();
+        info.StartAtLeftBoundary = _terminal->GetSelectionAnchor().x == bufferSize.Left();
+        info.EndAtRightBoundary = _terminal->GetSelectionEnd().x == bufferSize.RightInclusive();
         return info;
     }
 
diff --git a/src/cascadia/TerminalControl/ControlCore.h b/src/cascadia/TerminalControl/ControlCore.h
index b4017b08806..e11bd19772a 100644
--- a/src/cascadia/TerminalControl/ControlCore.h
+++ b/src/cascadia/TerminalControl/ControlCore.h
@@ -159,7 +159,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         bool HasSelection() const;
         bool CopyOnSelect() const;
         Windows::Foundation::Collections::IVector<winrt::hstring> SelectedText(bool trimTrailingWhitespace) const;
-        Control::SelectionMarkerMetadata SelectionMarkerInfo() const;
+        Control::SelectionData SelectionInfo() const;
         void SetSelectionAnchor(const til::point position);
         void SetEndSelectionPoint(const til::point position);
 
diff --git a/src/cascadia/TerminalControl/ControlCore.idl b/src/cascadia/TerminalControl/ControlCore.idl
index 82bd902c52c..1dc39842f97 100644
--- a/src/cascadia/TerminalControl/ControlCore.idl
+++ b/src/cascadia/TerminalControl/ControlCore.idl
@@ -29,14 +29,14 @@ namespace Microsoft.Terminal.Control
         All
     };
 
-    struct SelectionMarkerMetadata
+    struct SelectionData
     {
         Microsoft.Terminal.Core.Point StartPos;
         Microsoft.Terminal.Core.Point EndPos;
         Boolean MovingEnd;
         Boolean MovingCursor;
-        Boolean FlipStartMarker;
-        Boolean FlipEndMarker;
+        Boolean StartAtLeftBoundary;
+        Boolean EndAtRightBoundary;
     };
 
     [default_interface] runtimeclass ControlCore : ICoreState
@@ -100,7 +100,7 @@ namespace Microsoft.Terminal.Control
 
         Boolean HasSelection { get; };
         IVector<String> SelectedText(Boolean trimTrailingWhitespace);
-        SelectionMarkerMetadata SelectionMarkerInfo { get; };
+        SelectionData SelectionInfo { get; };
 
         String HoveredUriText { get; };
         Windows.Foundation.IReference<Microsoft.Terminal.Core.Point> HoveredCell { get; };
diff --git a/src/cascadia/TerminalControl/TermControl.cpp b/src/cascadia/TerminalControl/TermControl.cpp
index 2ca6a972781..be3c8ad0cab 100644
--- a/src/cascadia/TerminalControl/TermControl.cpp
+++ b/src/cascadia/TerminalControl/TermControl.cpp
@@ -2796,12 +2796,12 @@ namespace winrt::Microsoft::Terminal::Control::implementation
             {
                 // retrieve all of the necessary selection marker data
                 // from the TerminalCore layer under one lock to improve performance
-                const auto markerData{ _core.SelectionMarkerInfo() };
+                const auto markerData{ _core.SelectionInfo() };
 
                 // lambda helper function that can be used to display a selection marker
                 // - targetEnd: if true, target the "end" selection marker. Otherwise, target "start".
                 auto displayMarker = [&](bool targetEnd) {
-                    const auto flipMarker{ targetEnd ? markerData.FlipEndMarker : markerData.FlipStartMarker };
+                    const auto flipMarker{ targetEnd ? markerData.EndAtRightBoundary : markerData.StartAtLeftBoundary };
                     const auto& marker{ targetEnd ? SelectionEndMarker() : SelectionStartMarker() };
 
                     // Ensure the marker is oriented properly

From 326dadf2b8f6e1290b4e8e09482952fd5a875798 Mon Sep 17 00:00:00 2001
From: Carlos Zamora <cazamor@microsoft.com>
Date: Fri, 17 Jun 2022 12:24:06 -0700
Subject: [PATCH 10/10] change marker color to cursor color

---
 src/cascadia/TerminalControl/TermControl.cpp | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/cascadia/TerminalControl/TermControl.cpp b/src/cascadia/TerminalControl/TermControl.cpp
index be3c8ad0cab..fb44871fdd6 100644
--- a/src/cascadia/TerminalControl/TermControl.cpp
+++ b/src/cascadia/TerminalControl/TermControl.cpp
@@ -360,9 +360,9 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         _changeBackgroundColor(bg);
 
         // Update selection markers
-        Windows::UI::Xaml::Media::SolidColorBrush selectionBackgroundBrush{ til::color{ newAppearance.SelectionBackground() } };
-        SelectionStartMarker().Fill(selectionBackgroundBrush);
-        SelectionEndMarker().Fill(selectionBackgroundBrush);
+        Windows::UI::Xaml::Media::SolidColorBrush cursorColorBrush{ til::color{ newAppearance.CursorColor() } };
+        SelectionStartMarker().Fill(cursorColorBrush);
+        SelectionEndMarker().Fill(cursorColorBrush);
 
         // Set TSF Foreground
         Media::SolidColorBrush foregroundBrush{};