From c153fc719a5fc69e14e3a18b03693b86dc63619c Mon Sep 17 00:00:00 2001
From: Vlad Zahorodnii <vlad.zahorodnii@kde.org>
Date: Sat, 9 Dec 2023 14:37:12 +0200
Subject: [PATCH] scene: Make top left corner of CursorItem match the hotspot

It's more convenient if one wants to paint cursor at the specified
location. For example, when drawing the cursor on your own.
---
 src/scene/cursoritem.cpp  | 12 ++++++++----
 src/scene/cursoritem.h    |  4 ++--
 src/scene/cursorscene.cpp |  2 +-
 3 files changed, 11 insertions(+), 7 deletions(-)

diff --git a/src/scene/cursoritem.cpp b/src/scene/cursoritem.cpp
index 014f5516a1..160d408208 100644
--- a/src/scene/cursoritem.cpp
+++ b/src/scene/cursoritem.cpp
@@ -31,13 +31,13 @@ void CursorItem::refresh()
 {
     const CursorSource *source = Cursors::self()->currentCursor()->source();
     if (auto surfaceSource = qobject_cast<const SurfaceCursorSource *>(source)) {
-        setSurface(surfaceSource->surface());
+        setSurface(surfaceSource->surface(), surfaceSource->hotspot());
     } else if (auto shapeSource = qobject_cast<const ShapeCursorSource *>(source)) {
-        setImage(shapeSource->image());
+        setImage(shapeSource->image(), shapeSource->hotspot());
     }
 }
 
-void CursorItem::setSurface(SurfaceInterface *surface)
+void CursorItem::setSurface(SurfaceInterface *surface, const QPointF &hotspot)
 {
     m_imageItem.reset();
 
@@ -48,9 +48,12 @@ void CursorItem::setSurface(SurfaceInterface *surface)
             m_surfaceItem.reset();
         }
     }
+    if (m_surfaceItem) {
+        m_surfaceItem->setPosition(-hotspot);
+    }
 }
 
-void CursorItem::setImage(const QImage &image)
+void CursorItem::setImage(const QImage &image, const QPointF &hotspot)
 {
     m_surfaceItem.reset();
 
@@ -58,6 +61,7 @@ void CursorItem::setImage(const QImage &image)
         m_imageItem = scene()->renderer()->createImageItem(scene(), this);
     }
     m_imageItem->setImage(image);
+    m_imageItem->setPosition(-hotspot);
     m_imageItem->setSize(image.size() / image.devicePixelRatio());
 }
 
diff --git a/src/scene/cursoritem.h b/src/scene/cursoritem.h
index ca934c1107..22650ceb5a 100644
--- a/src/scene/cursoritem.h
+++ b/src/scene/cursoritem.h
@@ -25,8 +25,8 @@ public:
 
 private:
     void refresh();
-    void setSurface(SurfaceInterface *surface);
-    void setImage(const QImage &image);
+    void setSurface(SurfaceInterface *surface, const QPointF &hotspot);
+    void setImage(const QImage &image, const QPointF &hotspot);
 
     std::unique_ptr<ImageItem> m_imageItem;
     std::unique_ptr<SurfaceItemWayland> m_surfaceItem;
diff --git a/src/scene/cursorscene.cpp b/src/scene/cursorscene.cpp
index 49a118e9f3..912e5caf1d 100644
--- a/src/scene/cursorscene.cpp
+++ b/src/scene/cursorscene.cpp
@@ -55,7 +55,7 @@ void CursorScene::postPaint()
 
 void CursorScene::paint(const RenderTarget &renderTarget, const QRegion &region)
 {
-    RenderViewport viewport(QRectF(QPointF(), QSizeF(renderTarget.size()) / m_paintedOutput->scale()), m_paintedOutput->scale(), renderTarget);
+    RenderViewport viewport(QRectF(geometry().topLeft(), QSizeF(renderTarget.size()) / m_paintedOutput->scale()), m_paintedOutput->scale(), renderTarget);
     m_renderer->beginFrame(renderTarget, viewport);
     m_renderer->renderBackground(renderTarget, viewport, region);
     m_renderer->renderItem(renderTarget, viewport, m_rootItem.get(), 0, region, WindowPaintData{});