scene: add the presentation hint to Item

With this, the RenderLoop can use the Item instead of having to directly
deal with Wayland surfaces

src/compositor.cpp

@@ -167,11 +167,10 @@ void Compositor::composite(RenderLoop *renderLoop)
         prePaintPass(superLayer, &surfaceDamage);
 
         SurfaceItem *scanoutCandidate = superLayer->delegate()->scanoutCandidate();
-        const SurfaceItemWayland *scanoutCandidateWayland = qobject_cast<SurfaceItemWayland *>(scanoutCandidate);
         renderLoop->setFullscreenSurface(scanoutCandidate);
         frame->setContentType(scanoutCandidate ? scanoutCandidate->contentType() : ContentType::None);
         const bool vrr = (output->capabilities() & Output::Capability::Vrr) && (output->vrrPolicy() == VrrPolicy::Always || (output->vrrPolicy() == VrrPolicy::Automatic && scanoutCandidate));
-        const bool tearing = (output->capabilities() & Output::Capability::Tearing) && options->allowTearing() && scanoutCandidateWayland && scanoutCandidateWayland->surface()->presentationHint() == PresentationHint::Async;
+        const bool tearing = (output->capabilities() & Output::Capability::Tearing) && options->allowTearing() && scanoutCandidate && scanoutCandidate->presentationHint() == PresentationModeHint::Async;
         if (vrr) {
             frame->setPresentationMode(tearing ? PresentationMode::AdaptiveAsync : PresentationMode::AdaptiveSync);
         } else {

src/core/renderloop_p.h

@@ -46,7 +46,6 @@ public:
     Item *fullscreenItem = nullptr;
 
     PresentationMode presentationMode = PresentationMode::VSync;
-    bool canDoTearing = false;
 };
 
 } // namespace KWin

src/effect/globals.h

@@ -296,6 +296,12 @@ enum class VrrPolicy {
 };
 Q_ENUM_NS(VrrPolicy);
 
+enum class PresentationModeHint {
+    VSync,
+    Async
+};
+Q_ENUM_NS(PresentationModeHint);
+
 } // namespace
 
 Q_DECLARE_METATYPE(std::chrono::nanoseconds)

src/scene/item.cpp

@@ -452,6 +452,16 @@ void Item::setColorDescription(const ColorDescription &description)
     m_colorDescription = description;
 }
 
+PresentationModeHint Item::presentationHint() const
+{
+    return m_presentationHint;
+}
+
+void Item::setPresentationHint(PresentationModeHint hint)
+{
+    m_presentationHint = hint;
+}
+
 } // namespace KWin
 
 #include "moc_item.cpp"

src/scene/item.h

@@ -7,6 +7,7 @@
 #pragma once
 
 #include "core/colorspace.h"
+#include "effect/globals.h"
 #include "scene/itemgeometry.h"
 
 #include <QList>
@@ -112,6 +113,7 @@ public:
     WindowQuadList quads() const;
     virtual void preprocess();
     const ColorDescription &colorDescription() const;
+    PresentationModeHint presentationHint() const;
 
 Q_SIGNALS:
     void childAdded(Item *item);
@@ -134,6 +136,7 @@ protected:
     virtual WindowQuadList buildQuads() const;
     void discardQuads();
     void setColorDescription(const ColorDescription &description);
+    void setPresentationHint(PresentationModeHint hint);
 
 private:
     void addChild(Item *item);
@@ -162,6 +165,7 @@ private:
     mutable std::optional<WindowQuadList> m_quads;
     mutable std::optional<QList<Item *>> m_sortedChildItems;
     ColorDescription m_colorDescription = ColorDescription::sRGB;
+    PresentationModeHint m_presentationHint = PresentationModeHint::VSync;
 };
 
 } // namespace KWin

src/scene/surfaceitem_wayland.cpp

@@ -42,6 +42,8 @@ SurfaceItemWayland::SurfaceItemWayland(SurfaceInterface *surface, Scene *scene,
             this, &SurfaceItemWayland::handleChildSubSurfaceRemoved);
     connect(surface, &SurfaceInterface::colorDescriptionChanged,
             this, &SurfaceItemWayland::handleColorDescriptionChanged);
+    connect(surface, &SurfaceInterface::presentationModeHintChanged,
+            this, &SurfaceItemWayland::handlePresentationModeHintChanged);
 
     SubSurfaceInterface *subsurface = surface->subSurface();
     if (subsurface) {
@@ -189,6 +191,11 @@ void SurfaceItemWayland::handleColorDescriptionChanged()
     setColorDescription(m_surface->colorDescription());
 }
 
+void SurfaceItemWayland::handlePresentationModeHintChanged()
+{
+    setPresentationHint(m_surface->presentationModeHint());
+}
+
 SurfacePixmapWayland::SurfacePixmapWayland(SurfaceItemWayland *item, QObject *parent)
     : SurfacePixmap(Compositor::self()->backend()->createSurfaceTextureWayland(this), parent)
     , m_item(item)

src/scene/surfaceitem_wayland.h

@@ -48,6 +48,7 @@ private Q_SLOTS:
     void handleSubSurfacePositionChanged();
     void handleSubSurfaceMappedChanged();
     void handleColorDescriptionChanged();
+    void handlePresentationModeHintChanged();
 
 protected:
     std::unique_ptr<SurfacePixmap> createPixmap() override;

src/wayland/surface.cpp

@@ -641,9 +641,9 @@ void SurfaceState::mergeInto(SurfaceState *target)
         target->contentType = contentType;
         target->contentTypeIsSet = true;
     }
-    if (tearingIsSet) {
+    if (presentationModeHintIsSet) {
         target->presentationHint = presentationHint;
-        target->tearingIsSet = true;
+        target->presentationModeHintIsSet = true;
     }
     if (colorDescriptionIsSet) {
         target->colorDescription = colorDescription;
@@ -671,6 +671,7 @@ void SurfaceInterfacePrivate::applyState(SurfaceState *next)
     const bool subsurfaceOrderChanged = next->subsurfaceOrderChanged;
     const bool visibilityChanged = bufferChanged && bool(current->buffer) != bool(next->buffer);
     const bool colorDescriptionChanged = next->colorDescriptionIsSet;
+    const bool presentationModeHintChanged = next->presentationModeHintIsSet;
 
     const QSizeF oldSurfaceSize = surfaceSize;
     const QSize oldBufferSize = bufferSize;
@@ -769,6 +770,9 @@ void SurfaceInterfacePrivate::applyState(SurfaceState *next)
     if (colorDescriptionChanged) {
         Q_EMIT q->colorDescriptionChanged();
     }
+    if (presentationModeHintChanged) {
+        Q_EMIT q->presentationModeHintChanged();
+    }
 
     if (bufferChanged) {
         if (current->buffer && (!current->damage.isEmpty() || !current->bufferDamage.isEmpty())) {
@@ -1154,7 +1158,7 @@ QPointF SurfaceInterface::toSurfaceLocal(const QPointF &point) const
     return QPointF(point.x() * d->scaleOverride, point.y() * d->scaleOverride);
 }
 
-PresentationHint SurfaceInterface::presentationHint() const
+PresentationModeHint SurfaceInterface::presentationModeHint() const
 {
     return d->current->presentationHint;
 }

src/wayland/surface.h

@@ -34,11 +34,6 @@ class SubSurfaceInterface;
 class SurfaceInterfacePrivate;
 class Transaction;
 
-enum class PresentationHint {
-    VSync,
-    Async
-};
-
 /**
  * The SurfaceRole class represents a role assigned to a wayland surface.
  */
@@ -347,7 +342,7 @@ public:
     /**
      * @returns if the client thinks the content of this surface is suitable for presentation with tearing
      */
-    PresentationHint presentationHint() const;
+    PresentationModeHint presentationModeHint() const;
 
     /**
      * Sets a preferred buffer scale that clients should provide buffers in
@@ -470,6 +465,7 @@ Q_SIGNALS:
     void inhibitsIdleChanged();
 
     void colorDescriptionChanged();
+    void presentationModeHintChanged();
 
     /**
      * Emitted when the Surface has been committed.

src/wayland/surface_p.h

@@ -55,7 +55,7 @@ struct SurfaceState
     bool bufferScaleIsSet = false;
     bool bufferTransformIsSet = false;
     bool contentTypeIsSet = false;
-    bool tearingIsSet = false;
+    bool presentationModeHintIsSet = false;
     bool colorDescriptionIsSet = false;
     qint32 bufferScale = 1;
     OutputTransform bufferTransform = OutputTransform::Normal;
@@ -67,7 +67,7 @@ struct SurfaceState
     QPointer<ContrastInterface> contrast;
     QPointer<SlideInterface> slide;
     ContentType contentType = ContentType::None;
-    PresentationHint presentationHint = PresentationHint::VSync;
+    PresentationModeHint presentationHint = PresentationModeHint::VSync;
     ColorDescription colorDescription = ColorDescription::sRGB;
     std::unique_ptr<PresentationTimeFeedback> presentationFeedback;
 

src/wayland/tearingcontrol_v1.cpp

@@ -74,8 +74,8 @@ TearingControlV1Interface::~TearingControlV1Interface()
 {
     if (m_surface) {
         SurfaceInterfacePrivate *surfacePrivate = SurfaceInterfacePrivate::get(m_surface);
-        surfacePrivate->pending->presentationHint = PresentationHint::VSync;
-        surfacePrivate->pending->tearingIsSet = true;
+        surfacePrivate->pending->presentationHint = PresentationModeHint::VSync;
+        surfacePrivate->pending->presentationModeHintIsSet = true;
         surfacePrivate->tearing = nullptr;
     }
 }
@@ -85,11 +85,11 @@ void TearingControlV1Interface::wp_tearing_control_v1_set_presentation_hint(Reso
     if (m_surface) {
         SurfaceInterfacePrivate *surfacePrivate = SurfaceInterfacePrivate::get(m_surface);
         if (hint == presentation_hint::presentation_hint_async) {
-            surfacePrivate->pending->presentationHint = PresentationHint::Async;
+            surfacePrivate->pending->presentationHint = PresentationModeHint::Async;
         } else {
-            surfacePrivate->pending->presentationHint = PresentationHint::VSync;
+            surfacePrivate->pending->presentationHint = PresentationModeHint::VSync;
         }
-        surfacePrivate->pending->tearingIsSet = true;
+        surfacePrivate->pending->presentationModeHintIsSet = true;
     }
 }