diff --git a/Plugins/ZShell/Blobs/blobgroup.cpp b/Plugins/ZShell/Blobs/blobgroup.cpp
index e77cf05..62eef10 100644
--- a/Plugins/ZShell/Blobs/blobgroup.cpp
+++ b/Plugins/ZShell/Blobs/blobgroup.cpp
@@ -85,6 +85,8 @@ void BlobGroup::markShapeDirty(BlobShape* source) {
 		const QRectF otherRect(static_cast<double>(shape->m_cachedPaddedX), static_cast<double>(shape->m_cachedPaddedY),
 		                       static_cast<double>(shape->m_cachedPaddedW), static_cast<double>(shape->m_cachedPaddedH));
 		if (srcRect.intersects(otherRect)) {
+			shape->setExpandedRect(srcRect);
+			shape->m_hasExpandedRect = true;
 			shape->polish();
 			shape->update();
 		}
diff --git a/Plugins/ZShell/Blobs/blobshape.cpp b/Plugins/ZShell/Blobs/blobshape.cpp
index d872714..69d9ea6 100644
--- a/Plugins/ZShell/Blobs/blobshape.cpp
+++ b/Plugins/ZShell/Blobs/blobshape.cpp
@@ -69,26 +69,6 @@ void BlobShape::geometryChange(const QRectF& newGeometry, const QRectF& oldGeome
 	QQuickItem::geometryChange(newGeometry, oldGeometry);
 	updateCenteredDeformMatrix();
 	if (m_group) {
-		// Update cached values so markShapeDirty uses current geometry
-		const QPointF scenePos = mapToScene(QPointF(0, 0));
-		if (isInvertedRect()) {
-			m_cachedPaddedX = static_cast<float>(scenePos.x());
-			m_cachedPaddedY = static_cast<float>(scenePos.y());
-			m_cachedPaddedW = static_cast<float>(width());
-			m_cachedPaddedH = static_cast<float>(height());
-			m_localPaddedRect = QRectF(0, 0, width(), height());
-		} else {
-			const float hw = static_cast<float>(width()) * 0.5f;
-			const float hh = static_cast<float>(height()) * 0.5f;
-			const float totalPad = static_cast<float>(m_group->smoothing()) + deformPadding(m_deformMatrix, hw, hh);
-			m_cachedPaddedX = static_cast<float>(scenePos.x()) - totalPad;
-			m_cachedPaddedY = static_cast<float>(scenePos.y()) - totalPad;
-			m_cachedPaddedW = static_cast<float>(width()) + 2.0f * totalPad;
-			m_cachedPaddedH = static_cast<float>(height()) + 2.0f * totalPad;
-			m_localPaddedRect = QRectF(static_cast<double>(-totalPad), static_cast<double>(-totalPad),
-			                           width() + 2.0 * static_cast<double>(totalPad), height() + 2.0 * static_cast<double>(totalPad));
-		}
-
 		// Accumulate sub-pixel drift so slow movements don't desync the shader
 		m_pendingDx += static_cast<float>(newGeometry.x() - oldGeometry.x());
 		m_pendingDy += static_cast<float>(newGeometry.y() - oldGeometry.y());
@@ -138,6 +118,8 @@ void BlobShape::updatePolish() {
 	if (!m_group)
 		return;
 
+	m_hasExpandedRect = false;
+
 	// Ensure all shapes have up-to-date physics (only once per frame)
 	m_group->ensurePhysicsUpdated();
 
@@ -186,18 +168,20 @@ void BlobShape::updatePolish() {
 
 		const QPointF otherScene = other->mapToScene(QPointF(0, 0));
 
-		bool include = false;
-		if (isInvertedRect()) {
-			include = true;
-		} else {
-			const float otherHW = static_cast<float>(other->width()) * 0.5f;
-			const float otherHH = static_cast<float>(other->height()) * 0.5f;
-			const float otherPad = pad + deformPadding(other->m_deformMatrix, otherHW, otherHH);
-			const QRectF otherPadded(otherScene.x() - static_cast<double>(otherPad),
-			                         otherScene.y() - static_cast<double>(otherPad), other->width() + 2.0 * static_cast<double>(otherPad),
-			                         other->height() + 2.0 * static_cast<double>(otherPad));
-			include = myPadded.intersects(otherPadded);
-		}
+bool include = false;
+ 		if (isInvertedRect()) {
+ 			include = true;
+ 		} else if (m_hasExpandedRect) {
+ 			include = m_expandedRect.intersects(otherPadded);
+ 		} else {
+ 			const float otherHW = static_cast<float>(other->width()) * 0.5f;
+ 			const float otherHH = static_cast<float>(other->height()) * 0.5f;
+ 			const float otherPad = pad + deformPadding(other->m_deformMatrix, otherHW, otherHH);
+ 			const QRectF otherPadded(otherScene.x() - static_cast<double>(otherPad),
+ 			                         otherScene.y() - static_cast<double>(otherPad), other->width() + 2.0 * static_cast<double>(otherPad),
+ 			                         other->height() + 2.0 * static_cast<double>(otherPad));
+ 			include = myPadded.intersects(otherPadded);
+ 		}
 
 		if (include) {
 			if (other == this)
diff --git a/Plugins/ZShell/Blobs/blobshape.hpp b/Plugins/ZShell/Blobs/blobshape.hpp
index aa1d018..02c18c7 100644
--- a/Plugins/ZShell/Blobs/blobshape.hpp
+++ b/Plugins/ZShell/Blobs/blobshape.hpp
@@ -67,10 +67,20 @@ virtual void updatePhysics() {
 }
 
 virtual void registerWithGroup();
-virtual void unregisterFromGroup();
-void updateCenteredDeformMatrix();
+ virtual void unregisterFromGroup();
+ void updateCenteredDeformMatrix();
 
-BlobGroup* m_group = nullptr;
+ void setExpandedRect(const QRectF& rect) {
+ 	m_expandedRect = rect;
+ }
+ const QRectF& expandedRect() const {
+ 	return m_expandedRect;
+ }
+ bool hasExpandedRect() const {
+ 	return m_hasExpandedRect;
+ }
+
+ BlobGroup* m_group = nullptr;
 qreal m_radius = 0;
 QMatrix4x4 m_deformMatrix;     // identity by default
 QMatrix4x4 m_centeredDeformMatrix;
@@ -88,5 +98,8 @@ float m_pendingDy = 0;
 bool m_cachedHasInverted = false;
 float m_cachedInvertedRadius = 0;
 float m_cachedInvertedOuter[4] = {};
-float m_cachedInvertedInner[4] = {};
+ float m_cachedInvertedInner[4] = {};
+
+ QRectF m_expandedRect;
+ bool m_hasExpandedRect = false;
 };