Render row-by-row instead of invalidating entire screen

src/cascadia/TerminalCore/Terminal.cpp

@@ -701,6 +701,7 @@ void Terminal::_AdjustCursorPosition(const COORD proposedPosition)
 
     if (notifyScroll)
     {
+        // TODO: don't do this, thanks migrie
         _buffer->GetRenderTarget().TriggerRedrawAll();
         _NotifyScrollEvent();
     }

src/inc/til.h

@@ -11,8 +11,8 @@
 #include "til/some.h"
 #include "til/size.h"
 #include "til/point.h"
-#include "til/rectangle.h"
 #include "til/operators.h"
+#include "til/rectangle.h"
 #include "til/bitmap.h"
 #include "til/u8u16convert.h"
 

src/inc/til/bitmap.h

@@ -273,7 +273,7 @@ namespace til // Terminal Implementation Library. Also: "Today I Learned"
             THROW_HR_IF(E_INVALIDARG, !_rc.contains(pt));
             _runs.reset(); // reset cached runs on any non-const method
 
-            til::at(_bits, _rc.index_of(pt)) = true;
+            _bits.set(_rc.index_of(pt));
 
             _dirty |= til::rectangle{ pt };
         }
@@ -283,9 +283,9 @@ namespace til // Terminal Implementation Library. Also: "Today I Learned"
             THROW_HR_IF(E_INVALIDARG, !_rc.contains(rc));
             _runs.reset(); // reset cached runs on any non-const method
 
-            for (const auto pt : rc)
+            for (auto row = rc.top(); row < rc.bottom(); ++row)
             {
-                til::at(_bits, _rc.index_of(pt)) = true;
+                _bits.set(_rc.index_of(til::point{ rc.left(), row }), rc.width(), true);
             }
 
             _dirty |= rc;
@@ -378,6 +378,11 @@ namespace til // Terminal Implementation Library. Also: "Today I Learned"
             return _dirty == _rc;
         }
 
+        constexpr til::size size() const noexcept
+        {
+            return _sz;
+        }
+
         std::wstring to_string() const
         {
             std::wstringstream wss;

src/inc/til/operators.h

@@ -3,10 +3,6 @@
 
 #pragma once
 
-#include "rectangle.h"
-#include "size.h"
-#include "bitmap.h"
-
 namespace til // Terminal Implementation Library. Also: "Today I Learned"
 {
     // Operators go here when they involve two headers that can't/don't include each other.

src/inc/til/rectangle.h

@@ -3,10 +3,6 @@
 
 #pragma once
 
-#include "point.h"
-#include "size.h"
-#include "some.h"
-
 #ifdef UNIT_TESTING
 class RectangleTests;
 #endif
@@ -636,6 +632,32 @@ namespace til // Terminal Implementation Library. Also: "Today I Learned"
             return *this;
         }
 
+        // MUL will scale the entire rectangle up by the size factor
+        rectangle operator*(const size& size)
+        {
+            auto topLeft = _topLeft;
+            auto bottomRight = _bottomRight;
+            topLeft = topLeft * size;
+            bottomRight = bottomRight * size;
+            return til::rectangle{ topLeft, bottomRight };
+        }
+
+        // DIV will scale the entire rectangle down by the size factor,
+        // but rounds the bottom-right corner out.
+        rectangle operator/(const size& size)
+        {
+            auto topLeft = _topLeft;
+            auto bottomRight = _bottomRight;
+            topLeft = topLeft / size;
+
+            // Move bottom right point into a size
+            // Use size specialization of divide_ceil to round up against the size given.
+            // Add leading addition to point to convert it back into a point.
+            bottomRight = til::point{} + til::size{ right(), bottom() }.divide_ceil(size);
+
+            return til::rectangle{ topLeft, bottomRight };
+        }
+
 #pragma endregion
 
         constexpr ptrdiff_t top() const noexcept