[plasma/kwin] src: Fix geometry confining when resizing window by bottom-left corner

Git commit ca4bd9d09f99e10093a87d4edc61110b155c0051 by Vlad Zahorodnii.
Committed on 20/07/2026 at 06:36.
Pushed by vladz into branch 'master'.

Fix geometry confining when resizing window by bottom-left corner

The confining algorithm picks an anchor either in the top-left or the
top-right corner. So, the geometry constraining code has to do the same.

    case Gravity::BottomLeft:
    case Gravity::Bottom:
    case Gravity::BottomRight:
        constrainedRect.setTop(std::max(constrainedRect.top(), geometry.top() + minFrameSize.height()));
        constrainedRect.setBottom(std::min(constrainedRect.bottom(), geometry.top() + maxFrameSize.height()));
        break;

is rather for the case where the anchor lies at the bottom edge of the
window. It is a copy paste error.

This should fix issues such as a window getting unexpectedly shrunk or
grown when resizing by dragging the bottom-left or the bottom-right
corner.

M  +3    -7    src/window.cpp

https://invent.kde.org/plasma/kwin/-/commit/ca4bd9d09f99e10093a87d4edc61110b155c0051

diff --git a/src/window.cpp b/src/window.cpp
index 6fa3db05d0d..c4fc876a672 100644
--- a/src/window.cpp
+++ b/src/window.cpp
@@ -1471,6 +1471,9 @@ std::optional<QPointF> Window::confineInteractiveResize(const RectF &geometry, G
         case Gravity::TopLeft:
         case Gravity::Top:
         case Gravity::TopRight:
+        case Gravity::BottomLeft:
+        case Gravity::Bottom:
+        case Gravity::BottomRight:
             constrainedRect.setBottom(std::min(constrainedRect.bottom(), geometry.bottom() - minFrameSize.height()));
             constrainedRect.setTop(std::max(constrainedRect.top(), geometry.bottom() - maxFrameSize.height()));
             break;
@@ -1479,13 +1482,6 @@ std::optional<QPointF> Window::confineInteractiveResize(const RectF &geometry, G
         case Gravity::Right:
             break;
 
-        case Gravity::BottomLeft:
-        case Gravity::Bottom:
-        case Gravity::BottomRight:
-            constrainedRect.setTop(std::max(constrainedRect.top(), geometry.top() + minFrameSize.height()));
-            constrainedRect.setBottom(std::min(constrainedRect.bottom(), geometry.top() + maxFrameSize.height()));
-            break;
-
         case Gravity::None:
             Q_UNREACHABLE();
         }