Horizontal snapping à la vim

microsoft · Aug 5, 2024 · 1ade14e · 1ade14e
1 parent 5174c96
commit 1ade14e
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Showing 5 changed files with 94 additions and 23 deletions.
diff --git a/src/host/_stream.cpp b/src/host/_stream.cpp
@@ -206,6 +206,7 @@ void WriteCharsLegacy(SCREEN_INFORMATION& screenInfo, const std::wstring_view& t
             writer.Submit();
         }
 
+        screenInfo.SnapOnOutput();
         return;
     }
 
@@ -328,6 +329,8 @@ void WriteCharsLegacy(SCREEN_INFORMATION& screenInfo, const std::wstring_view& t
     {
         writer.Submit();
     }
+
+    screenInfo.SnapOnOutput();
 }
 
 // This is the main entrypoint for conhost to write VT to the buffer.
@@ -375,6 +378,8 @@ void WriteCharsVT(SCREEN_INFORMATION& screenInfo, const std::wstring_view& str)
         write(offset, std::wstring_view::npos);
         writer.Submit();
     }
+
+    screenInfo.SnapOnOutput();
 }
 
 // Erases all contents of the given screenInfo, including the current screen and scrollback.

diff --git a/src/host/input.cpp b/src/host/input.cpp
@@ -108,7 +108,7 @@ bool ShouldTakeOverKeyboardShortcuts()
 void HandleGenericKeyEvent(INPUT_RECORD event, const bool generateBreak)
 {
     auto& keyEvent = event.Event.KeyEvent;
-    const auto& gci = ServiceLocator::LocateGlobals().getConsoleInformation();
+    auto& gci = ServiceLocator::LocateGlobals().getConsoleInformation();
     auto ContinueProcessing = true;
 
     if (WI_IsAnyFlagSet(keyEvent.dwControlKeyState, CTRL_PRESSED) &&
@@ -167,6 +167,11 @@ void HandleGenericKeyEvent(INPUT_RECORD event, const bool generateBreak)
             keyEvent.bKeyDown = false;
             gci.pInputBuffer->Write(event);
         }
+
+        if (gci.HasActiveOutputBuffer())
+        {
+            gci.GetActiveOutputBuffer().SnapOnInput(keyEvent.wVirtualKeyCode);
+        }
     }
 }
 

diff --git a/src/host/screenInfo.cpp b/src/host/screenInfo.cpp
@@ -1669,39 +1669,85 @@ void SCREEN_INFORMATION::SetCursorDBMode(const bool DoubleCursor)
     return STATUS_SUCCESS;
 }
 
-void SCREEN_INFORMATION::MakeCursorVisible(const til::point CursorPosition)
+static constexpr bool IsInputKey(WORD vkey)
 {
-    til::point WindowOrigin;
+    return vkey != VK_CONTROL &&
+           vkey != VK_LCONTROL &&
+           vkey != VK_RCONTROL &&
+           vkey != VK_MENU &&
+           vkey != VK_LMENU &&
+           vkey != VK_RMENU &&
+           vkey != VK_SHIFT &&
+           vkey != VK_LSHIFT &&
+           vkey != VK_RSHIFT &&
+           vkey != VK_LWIN &&
+           vkey != VK_RWIN &&
+           vkey != VK_SNAPSHOT;
+}
 
-    if (CursorPosition.x > _viewport.RightInclusive())
-    {
-        WindowOrigin.x = CursorPosition.x - _viewport.RightInclusive();
-    }
-    else if (CursorPosition.x < _viewport.Left())
-    {
-        WindowOrigin.x = CursorPosition.x - _viewport.Left();
-    }
-    else
+void SCREEN_INFORMATION::MakeCursorVisible(til::point position)
+{
+    _makeLocationVisible(position, ViewportMovementMask::Vertical | ViewportMovementMask::Horizontal);
+}
+
+void SCREEN_INFORMATION::SnapOnInput(const WORD vkey)
+{
+    if (IsInputKey(vkey))
     {
-        WindowOrigin.x = 0;
+        _makeLocationVisible(_textBuffer->GetCursor().GetPosition(), ViewportMovementMask::Vertical);
     }
+}
 
-    if (CursorPosition.y > _viewport.BottomInclusive())
+void SCREEN_INFORMATION::SnapOnOutput()
+{
+    _makeLocationVisible(_textBuffer->GetCursor().GetPosition(), ViewportMovementMask::HorizontalCenter);
+}
+
+void SCREEN_INFORMATION::_makeLocationVisible(til::point position, ViewportMovementMask movements)
+{
+    const auto viewportOrigin = _viewport.Origin();
+    const auto viewportSize = _viewport.Dimensions();
+    const auto bufferSize = _textBuffer->GetSize().Dimensions();
+    auto origin = viewportOrigin;
+
+    // Ensure the given position is in bounds.
+    position.x = std::clamp(position.x, 0, bufferSize.width - 1);
+    position.y = std::clamp(position.y, 0, bufferSize.height - 1);
+
+    if (WI_IsAnyFlagSet(movements, ViewportMovementMask::Vertical))
     {
-        WindowOrigin.y = CursorPosition.y - _viewport.BottomInclusive();
+        origin.y = std::min(origin.y, position.y); // shift up if above
+        origin.y = std::max(origin.y, position.y - (viewportSize.height - 1)); // shift down if below
     }
-    else if (CursorPosition.y < _viewport.Top())
+
+    if (WI_IsAnyFlagSet(movements, ViewportMovementMask::Horizontal))
     {
-        WindowOrigin.y = CursorPosition.y - _viewport.Top();
+        origin.x = std::min(origin.x, position.x); // shift left if left
+        origin.x = std::max(origin.x, position.x - (viewportSize.width - 1)); // shift right if right
     }
-    else
+
+    if (WI_IsAnyFlagSet(movements, ViewportMovementMask::HorizontalCenter))
     {
-        WindowOrigin.y = 0;
+        // If the position is horizontally outside the viewport, snap the
+        // viewport to the nearest multiple of half the viewport width.
+        if (position.x < origin.x || position.x >= (origin.x + viewportSize.width))
+        {
+            const auto div = viewportSize.width / 2;
+            // We want our viewport to be centered around the position (= "half-width" offset).
+            // Since the origin is the left edge, we must subtract a half-width from the position.
+            origin.x = position.x - div;
+            // Round down to the nearest multiple of the viewport width.
+            // This also works if origin.x is negative, because the "modulo operator"
+            // is not a modulo operator, it's a remainder operator. The remainder of a
+            // negative number is negative and so origin.x cannot end up being less than 0.
+            origin.x -= origin.x % div;
+            origin.x = std::min(origin.x, bufferSize.width - viewportSize.width);
+        }
     }
 
-    if (WindowOrigin.x != 0 || WindowOrigin.y != 0)
+    if (origin != viewportOrigin)
     {
-        LOG_IF_FAILED(SetViewportOrigin(false, WindowOrigin, false));
+        std::ignore = SetViewportOrigin(true, origin, false);
     }
 }
 

diff --git a/src/host/screenInfo.hpp b/src/host/screenInfo.hpp
@@ -47,6 +47,14 @@ Revision History:
 #include "../types/inc/Viewport.hpp"
 class ConversionAreaInfo; // forward decl window. circular reference
 
+enum class ViewportMovementMask
+{
+    Vertical = 0x1,
+    Horizontal = 0x2,
+    HorizontalCenter = 0x4,
+};
+DEFINE_ENUM_FLAG_OPERATORS(ViewportMovementMask);
+
 class SCREEN_INFORMATION : public ConsoleObjectHeader, public Microsoft::Console::IIoProvider
 {
 public:
@@ -71,6 +79,9 @@ class SCREEN_INFORMATION : public ConsoleObjectHeader, public Microsoft::Console
     void GetRequiredConsoleSizeInPixels(_Out_ til::size* const pRequiredSize) const;
 
     void MakeCurrentCursorVisible();
+    void MakeCursorVisible(til::point position);
+    void SnapOnInput(WORD vkey);
+    void SnapOnOutput();
 
     void ClipToScreenBuffer(_Inout_ til::inclusive_rect* const psrClip) const;
 
@@ -184,8 +195,6 @@ class SCREEN_INFORMATION : public ConsoleObjectHeader, public Microsoft::Console
     void SetCursorDBMode(const bool DoubleCursor);
     [[nodiscard]] NTSTATUS SetCursorPosition(const til::point Position, const bool TurnOn);
 
-    void MakeCursorVisible(const til::point CursorPosition);
-
     [[nodiscard]] NTSTATUS UseAlternateScreenBuffer(const TextAttribute& initAttributes);
     void UseMainScreenBuffer();
 
@@ -235,6 +244,7 @@ class SCREEN_INFORMATION : public ConsoleObjectHeader, public Microsoft::Console
     void _CalculateViewportSize(const til::rect* const prcClientArea, _Out_ til::size* const pcoordSize);
     void _AdjustViewportSize(const til::rect* const prcClientNew, const til::rect* const prcClientOld, const til::size* const pcoordSize);
     void _InternalSetViewportSize(const til::size* pcoordSize, const bool fResizeFromTop, const bool fResizeFromLeft);
+    void _makeLocationVisible(til::point position, ViewportMovementMask movements);
 
     static void s_CalculateScrollbarVisibility(const til::rect* const prcClientArea,
                                                const til::size* const pcoordBufferSize,

diff --git a/src/interactivity/win32/Clipboard.cpp b/src/interactivity/win32/Clipboard.cpp
@@ -162,6 +162,11 @@ void Clipboard::StringPaste(_In_reads_(cchData) const wchar_t* const pData,
         const auto bracketedPasteMode = gci.GetBracketedPasteMode();
         auto inEvents = TextToKeyEvents(pData, cchData, vtInputMode && bracketedPasteMode);
         gci.pInputBuffer->Write(inEvents);
+
+        if (gci.HasActiveOutputBuffer())
+        {
+            gci.GetActiveOutputBuffer().SnapOnInput(0);
+        }
     }
     catch (...)
     {