wayland/screencopy: use linear texture filtering over nearest

Fixes pixelated views at scaled resolutions.

changelog/next.md

@@ -64,6 +64,7 @@ set shell id.
 - Fixed partial socket reads in greetd and hyprland on slow machines.
 - Worked around Qt bug causing crashes when plugging and unplugging monitors.
 - Fixed HyprlandFocusGrab crashing if windows were destroyed after being passed to it.
+- Fixed ScreencopyView pixelation when scaled.
 
 ## Packaging Changes
 

src/wayland/buffer/manager.cpp

@@ -123,6 +123,10 @@ void WlBufferQSGDisplayNode::setRect(const QRectF& rect) {
 	this->setMatrix(matrix);
 }
 
+void WlBufferQSGDisplayNode::setFiltering(QSGTexture::Filtering filtering) {
+	this->imageNode->setFiltering(filtering);
+}
+
 void WlBufferQSGDisplayNode::syncSwapchain(const WlBufferSwapchain& swapchain) {
 	auto* buffer = swapchain.frontbuffer();
 	auto& texture = swapchain.presentSecondBuffer ? this->buffer2 : this->buffer1;

src/wayland/buffer/qsg.hpp

@@ -33,6 +33,7 @@ public:
 
 	void syncSwapchain(const WlBufferSwapchain& swapchain);
 	void setRect(const QRectF& rect);
+	void setFiltering(QSGTexture::Filtering filtering);
 
 private:
 	QQuickWindow* window;

src/wayland/screencopy/view.cpp

@@ -167,6 +167,7 @@ QSGNode* ScreencopyView::updatePaintNode(QSGNode* oldNode, UpdatePaintNodeData*
 	auto& swapchain = this->context->swapchain();
 	node->syncSwapchain(swapchain);
 	node->setRect(this->boundingRect());
+	node->setFiltering(QSGTexture::Linear); // NOLINT (misc-include-cleaner)
 
 	if (this->mLive) this->context->captureFrame();
 	return node;