File indexing completed on 2024-05-19 16:35:28

 /*
     SPDX-FileCopyrightText: 2014 Martin Gräßlin <mgraesslin@kde.org>
     SPDX-FileCopyrightText: 2020 Vlad Zahorodnii <vlad.zahorodnii@kde.org>
 
     SPDX-License-Identifier: LGPL-2.1-only OR LGPL-3.0-only OR LicenseRef-KDE-Accepted-LGPL
 */
 #include "surface_interface.h"
 #include "clientbuffer.h"
 #include "clientconnection.h"
 #include "compositor_interface.h"
 #include "contenttype_v1_interface.h"
 #include "display.h"
 #include "fractionalscale_v1_interface_p.h"
 #include "idleinhibit_v1_interface_p.h"
 #include "linuxdmabufv1clientbuffer.h"
 #include "pointerconstraints_v1_interface_p.h"
 #include "region_interface_p.h"
 #include "subcompositor_interface.h"
 #include "subsurface_interface_p.h"
 #include "surface_interface_p.h"
 #include "surfacerole_p.h"
 #include "utils.h"
 
 #include <wayland-server.h>
 // std
 #include <algorithm>
 #include <cmath>
 
 namespace KWaylandServer
 {
 
 static QRegion map_helper(const QMatrix4x4 &matrix, const QRegion &region)
 {
     QRegion result;
     for (const QRect &rect : region) {
         result += matrix.mapRect(QRectF(rect)).toAlignedRect();
     }
     return result;
 }
 
 SurfaceInterfacePrivate::SurfaceInterfacePrivate(SurfaceInterface *q)
     : q(q)
 {
     wl_list_init(&current.frameCallbacks);
     wl_list_init(&pending.frameCallbacks);
     wl_list_init(&cached.frameCallbacks);
 }
 
 SurfaceInterfacePrivate::~SurfaceInterfacePrivate()
 {
     wl_resource *resource;
     wl_resource *tmp;
 
     wl_resource_for_each_safe (resource, tmp, &current.frameCallbacks) {
         wl_resource_destroy(resource);
     }
     wl_resource_for_each_safe (resource, tmp, &pending.frameCallbacks) {
         wl_resource_destroy(resource);
     }
     wl_resource_for_each_safe (resource, tmp, &cached.frameCallbacks) {
         wl_resource_destroy(resource);
     }
 
     if (current.buffer) {
         current.buffer->unref();
     }
 }
 
 void SurfaceInterfacePrivate::addChild(SubSurfaceInterface *child)
 {
     // protocol is not precise on how to handle the addition of new sub surfaces
     pending.above.append(child);
     cached.above.append(child);
     current.above.append(child);
     child->surface()->setOutputs(outputs);
     child->surface()->setPreferredScale(preferredScale);
 
     Q_EMIT q->childSubSurfaceAdded(child);
     Q_EMIT q->childSubSurfacesChanged();
 }
 
 void SurfaceInterfacePrivate::removeChild(SubSurfaceInterface *child)
 {
     // protocol is not precise on how to handle the addition of new sub surfaces
     pending.below.removeAll(child);
     pending.above.removeAll(child);
     cached.below.removeAll(child);
     cached.above.removeAll(child);
     current.below.removeAll(child);
     current.above.removeAll(child);
     Q_EMIT q->childSubSurfaceRemoved(child);
     Q_EMIT q->childSubSurfacesChanged();
 }
 
 bool SurfaceInterfacePrivate::raiseChild(SubSurfaceInterface *subsurface, SurfaceInterface *anchor)
 {
     Q_ASSERT(subsurface->parentSurface() == q);
 
     QList<SubSurfaceInterface *> *anchorList;
     int anchorIndex;
 
     pending.below.removeOne(subsurface);
     pending.above.removeOne(subsurface);
 
     if (anchor == q) {
         // Pretend as if the parent surface were before the first child in the above list.
         anchorList = &pending.above;
         anchorIndex = -1;
     } else if (anchorIndex = pending.above.indexOf(anchor->subSurface()); anchorIndex != -1) {
         anchorList = &pending.above;
     } else if (anchorIndex = pending.below.indexOf(anchor->subSurface()); anchorIndex != -1) {
         anchorList = &pending.below;
     } else {
         return false; // The anchor belongs to other sub-surface tree.
     }
 
     anchorList->insert(anchorIndex + 1, subsurface);
     pending.childrenChanged = true;
     return true;
 }
 
 bool SurfaceInterfacePrivate::lowerChild(SubSurfaceInterface *subsurface, SurfaceInterface *anchor)
 {
     Q_ASSERT(subsurface->parentSurface() == q);
 
     QList<SubSurfaceInterface *> *anchorList;
     int anchorIndex;
 
     pending.below.removeOne(subsurface);
     pending.above.removeOne(subsurface);
 
     if (anchor == q) {
         // Pretend as if the parent surface were after the last child in the below list.
         anchorList = &pending.below;
         anchorIndex = pending.below.count();
     } else if (anchorIndex = pending.above.indexOf(anchor->subSurface()); anchorIndex != -1) {
         anchorList = &pending.above;
     } else if (anchorIndex = pending.below.indexOf(anchor->subSurface()); anchorIndex != -1) {
         anchorList = &pending.below;
     } else {
         return false; // The anchor belongs to other sub-surface tree.
     }
 
     anchorList->insert(anchorIndex, subsurface);
     pending.childrenChanged = true;
     return true;
 }
 
 void SurfaceInterfacePrivate::setShadow(const QPointer<ShadowInterface> &shadow)
 {
     pending.shadow = shadow;
     pending.shadowIsSet = true;
 }
 
 void SurfaceInterfacePrivate::setBlur(const QPointer<BlurInterface> &blur)
 {
     pending.blur = blur;
     pending.blurIsSet = true;
 }
 
 void SurfaceInterfacePrivate::setSlide(const QPointer<SlideInterface> &slide)
 {
     pending.slide = slide;
     pending.slideIsSet = true;
 }
 
 void SurfaceInterfacePrivate::setContrast(const QPointer<ContrastInterface> &contrast)
 {
     pending.contrast = contrast;
     pending.contrastIsSet = true;
 }
 
 void SurfaceInterfacePrivate::installPointerConstraint(LockedPointerV1Interface *lock)
 {
     Q_ASSERT(!lockedPointer);
     Q_ASSERT(!confinedPointer);
 
     lockedPointer = lock;
 
     auto cleanUp = [this]() {
         lockedPointer = nullptr;
         QObject::disconnect(constrainsOneShotConnection);
         constrainsOneShotConnection = QMetaObject::Connection();
         QObject::disconnect(constrainsUnboundConnection);
         constrainsUnboundConnection = QMetaObject::Connection();
         Q_EMIT q->pointerConstraintsChanged();
     };
 
     if (lock->lifeTime() == LockedPointerV1Interface::LifeTime::OneShot) {
         constrainsOneShotConnection = QObject::connect(lock, &LockedPointerV1Interface::lockedChanged, q, [this, cleanUp] {
             if (lockedPointer->isLocked()) {
                 return;
             }
             cleanUp();
         });
     }
     constrainsUnboundConnection = QObject::connect(lock, &LockedPointerV1Interface::destroyed, q, cleanUp);
     Q_EMIT q->pointerConstraintsChanged();
 }
 
 void SurfaceInterfacePrivate::installPointerConstraint(ConfinedPointerV1Interface *confinement)
 {
     Q_ASSERT(!lockedPointer);
     Q_ASSERT(!confinedPointer);
 
     confinedPointer = confinement;
 
     auto cleanUp = [this]() {
         confinedPointer = nullptr;
         QObject::disconnect(constrainsOneShotConnection);
         constrainsOneShotConnection = QMetaObject::Connection();
         QObject::disconnect(constrainsUnboundConnection);
         constrainsUnboundConnection = QMetaObject::Connection();
         Q_EMIT q->pointerConstraintsChanged();
     };
 
     if (confinement->lifeTime() == ConfinedPointerV1Interface::LifeTime::OneShot) {
         constrainsOneShotConnection = QObject::connect(confinement, &ConfinedPointerV1Interface::confinedChanged, q, [this, cleanUp] {
             if (confinedPointer->isConfined()) {
                 return;
             }
             cleanUp();
         });
     }
     constrainsUnboundConnection = QObject::connect(confinement, &ConfinedPointerV1Interface::destroyed, q, cleanUp);
     Q_EMIT q->pointerConstraintsChanged();
 }
 
 void SurfaceInterfacePrivate::installIdleInhibitor(IdleInhibitorV1Interface *inhibitor)
 {
     idleInhibitors << inhibitor;
     QObject::connect(inhibitor, &IdleInhibitorV1Interface::destroyed, q, [this, inhibitor] {
         idleInhibitors.removeOne(inhibitor);
         if (idleInhibitors.isEmpty()) {
             Q_EMIT q->inhibitsIdleChanged();
         }
     });
     if (idleInhibitors.count() == 1) {
         Q_EMIT q->inhibitsIdleChanged();
     }
 }
 
 void SurfaceInterfacePrivate::surface_destroy_resource(Resource *)
 {
     Q_EMIT q->aboutToBeDestroyed();
     delete q;
 }
 
 void SurfaceInterfacePrivate::surface_destroy(Resource *resource)
 {
     wl_resource_destroy(resource->handle);
 }
 
 void SurfaceInterfacePrivate::surface_attach(Resource *resource, struct ::wl_resource *buffer, int32_t x, int32_t y)
 {
     if (wl_resource_get_version(resource->handle) >= WL_SURFACE_OFFSET_SINCE_VERSION) {
         if (x != 0 || y != 0) {
             wl_resource_post_error(resource->handle, error_invalid_offset, "wl_surface.attach offset must be 0");
             return;
         }
     } else {
         pending.offset = QPoint(x, y);
     }
 
     pending.bufferIsSet = true;
     if (!buffer) {
         // got a null buffer, deletes content in next frame
         pending.buffer = nullptr;
         pending.damage = QRegion();
         pending.bufferDamage = QRegion();
         return;
     }
     pending.buffer = compositor->display()->clientBufferForResource(buffer);
 }
 
 void SurfaceInterfacePrivate::surface_damage(Resource *, int32_t x, int32_t y, int32_t width, int32_t height)
 {
     pending.damage |= QRect(x, y, width, height);
 }
 
 void SurfaceInterfacePrivate::surface_frame(Resource *resource, uint32_t callback)
 {
     wl_resource *callbackResource = wl_resource_create(resource->client(),
                                                        &wl_callback_interface,
                                                        /* version */ 1,
                                                        callback);
     if (!callbackResource) {
         wl_resource_post_no_memory(resource->handle);
         return;
     }
 
     wl_resource_set_implementation(callbackResource, nullptr, nullptr, [](wl_resource *resource) {
         wl_list_remove(wl_resource_get_link(resource));
     });
 
     wl_list_insert(pending.frameCallbacks.prev, wl_resource_get_link(callbackResource));
 }
 
 void SurfaceInterfacePrivate::surface_set_opaque_region(Resource *resource, struct ::wl_resource *region)
 {
     RegionInterface *r = RegionInterface::get(region);
     pending.opaque = r ? r->region() : QRegion();
     pending.opaqueIsSet = true;
 }
 
 void SurfaceInterfacePrivate::surface_set_input_region(Resource *resource, struct ::wl_resource *region)
 {
     RegionInterface *r = RegionInterface::get(region);
     pending.input = r ? r->region() : infiniteRegion();
     pending.inputIsSet = true;
 }
 
 void SurfaceInterfacePrivate::surface_commit(Resource *resource)
 {
     if (subSurface) {
         commitSubSurface();
     } else {
         applyState(&pending);
     }
 }
 
 void SurfaceInterfacePrivate::surface_set_buffer_transform(Resource *resource, int32_t transform)
 {
     if (transform < 0 || transform > WL_OUTPUT_TRANSFORM_FLIPPED_270) {
         wl_resource_post_error(resource->handle, error_invalid_transform, "buffer transform must be a valid transform (%d specified)", transform);
         return;
     }
     pending.bufferTransform = KWin::Output::Transform(transform);
     pending.bufferTransformIsSet = true;
 }
 
 void SurfaceInterfacePrivate::surface_set_buffer_scale(Resource *resource, int32_t scale)
 {
     if (scale < 1) {
         wl_resource_post_error(resource->handle, error_invalid_scale, "buffer scale must be at least one (%d specified)", scale);
         return;
     }
     pending.bufferScale = scale;
     pending.bufferScaleIsSet = true;
 }
 
 void SurfaceInterfacePrivate::surface_damage_buffer(Resource *resource, int32_t x, int32_t y, int32_t width, int32_t height)
 {
     pending.bufferDamage |= QRect(x, y, width, height);
 }
 
 void SurfaceInterfacePrivate::surface_offset(Resource *resource, int32_t x, int32_t y)
 {
     pending.offset = QPoint(x, y);
 }
 
 SurfaceInterface::SurfaceInterface(CompositorInterface *compositor, wl_resource *resource)
     : QObject(compositor)
     , d(new SurfaceInterfacePrivate(this))
 {
     d->compositor = compositor;
     d->init(resource);
     d->client = compositor->display()->getConnection(d->resource()->client());
 
     d->pendingScaleOverride = d->client->scaleOverride();
     d->scaleOverride = d->pendingScaleOverride;
     connect(d->client, &ClientConnection::scaleOverrideChanged, this, [this]() {
         d->pendingScaleOverride = d->client->scaleOverride();
     });
 }
 
 SurfaceInterface::~SurfaceInterface()
 {
 }
 
 uint32_t SurfaceInterface::id() const
 {
     return wl_resource_get_id(resource());
 }
 
 ClientConnection *SurfaceInterface::client() const
 {
     return d->client;
 }
 
 wl_resource *SurfaceInterface::resource() const
 {
     return d->resource()->handle;
 }
 
 CompositorInterface *SurfaceInterface::compositor() const
 {
     return d->compositor;
 }
 
 void SurfaceInterface::frameRendered(quint32 msec)
 {
     // notify all callbacks
     wl_resource *resource;
     wl_resource *tmp;
 
     wl_resource_for_each_safe (resource, tmp, &d->current.frameCallbacks) {
         wl_callback_send_done(resource, msec);
         wl_resource_destroy(resource);
     }
 
     for (SubSurfaceInterface *subsurface : std::as_const(d->current.below)) {
         subsurface->surface()->frameRendered(msec);
     }
     for (SubSurfaceInterface *subsurface : std::as_const(d->current.above)) {
         subsurface->surface()->frameRendered(msec);
     }
 }
 
 bool SurfaceInterface::hasFrameCallbacks() const
 {
     return !wl_list_empty(&d->current.frameCallbacks);
 }
 
 QMatrix4x4 SurfaceInterfacePrivate::buildSurfaceToBufferMatrix()
 {
     // The order of transforms is reversed, i.e. the viewport transform is the first one.
 
     QMatrix4x4 surfaceToBufferMatrix;
 
     if (!current.buffer) {
         return surfaceToBufferMatrix;
     }
 
     surfaceToBufferMatrix.scale(current.bufferScale, current.bufferScale);
     surfaceToBufferMatrix.scale(scaleOverride, scaleOverride);
 
     switch (current.bufferTransform) {
     case KWin::Output::Transform::Normal:
     case KWin::Output::Transform::Flipped:
         break;
     case KWin::Output::Transform::Rotated90:
     case KWin::Output::Transform::Flipped90:
         surfaceToBufferMatrix.translate(0, bufferSize.height() / current.bufferScale);
         surfaceToBufferMatrix.rotate(-90, 0, 0, 1);
         break;
     case KWin::Output::Transform::Rotated180:
     case KWin::Output::Transform::Flipped180:
         surfaceToBufferMatrix.translate(bufferSize.width() / current.bufferScale, bufferSize.height() / current.bufferScale);
         surfaceToBufferMatrix.rotate(-180, 0, 0, 1);
         break;
     case KWin::Output::Transform::Rotated270:
     case KWin::Output::Transform::Flipped270:
         surfaceToBufferMatrix.translate(bufferSize.width() / current.bufferScale, 0);
         surfaceToBufferMatrix.rotate(-270, 0, 0, 1);
         break;
     }
 
     switch (current.bufferTransform) {
     case KWin::Output::Transform::Flipped:
     case KWin::Output::Transform::Flipped180:
         surfaceToBufferMatrix.translate(bufferSize.width() / current.bufferScale, 0);
         surfaceToBufferMatrix.scale(-1, 1);
         break;
     case KWin::Output::Transform::Flipped90:
     case KWin::Output::Transform::Flipped270:
         surfaceToBufferMatrix.translate(bufferSize.height() / current.bufferScale, 0);
         surfaceToBufferMatrix.scale(-1, 1);
         break;
     default:
         break;
     }
 
     if (current.viewport.sourceGeometry.isValid()) {
         surfaceToBufferMatrix.translate(current.viewport.sourceGeometry.x(), current.viewport.sourceGeometry.y());
     }
 
     QSizeF sourceSize;
     if (current.viewport.sourceGeometry.isValid()) {
         sourceSize = current.viewport.sourceGeometry.size();
     } else {
         sourceSize = implicitSurfaceSize;
     }
 
     if (sourceSize != surfaceSize) {
         surfaceToBufferMatrix.scale(sourceSize.width() / surfaceSize.width(), sourceSize.height() / surfaceSize.height());
     }
 
     return surfaceToBufferMatrix;
 }
 
 void SurfaceState::mergeInto(SurfaceState *target)
 {
     if (bufferIsSet) {
         target->buffer = buffer;
         target->offset = offset;
         target->damage = damage;
         target->bufferDamage = bufferDamage;
         target->bufferIsSet = bufferIsSet;
     }
     if (viewport.sourceGeometryIsSet) {
         target->viewport.sourceGeometry = viewport.sourceGeometry;
         target->viewport.sourceGeometryIsSet = true;
     }
     if (viewport.destinationSizeIsSet) {
         target->viewport.destinationSize = viewport.destinationSize;
         target->viewport.destinationSizeIsSet = true;
     }
     if (childrenChanged) {
         target->below = below;
         target->above = above;
         target->childrenChanged = true;
     }
     wl_list_insert_list(&target->frameCallbacks, &frameCallbacks);
 
     if (shadowIsSet) {
         target->shadow = shadow;
         target->shadowIsSet = true;
     }
     if (blurIsSet) {
         target->blur = blur;
         target->blurIsSet = true;
     }
     if (contrastIsSet) {
         target->contrast = contrast;
         target->contrastIsSet = true;
     }
     if (slideIsSet) {
         target->slide = slide;
         target->slideIsSet = true;
     }
     if (inputIsSet) {
         target->input = input;
         target->inputIsSet = true;
     }
     if (opaqueIsSet) {
         target->opaque = opaque;
         target->opaqueIsSet = true;
     }
     if (bufferScaleIsSet) {
         target->bufferScale = bufferScale;
         target->bufferScaleIsSet = true;
     }
     if (bufferTransformIsSet) {
         target->bufferTransform = bufferTransform;
         target->bufferTransformIsSet = true;
     }
     if (contentTypeIsSet) {
         target->contentType = contentType;
         target->contentTypeIsSet = true;
     }
     if (tearingIsSet) {
         target->presentationHint = presentationHint;
         target->tearingIsSet = true;
     }
 
     *this = SurfaceState{};
     below = target->below;
     above = target->above;
     wl_list_init(&frameCallbacks);
 }
 
 void SurfaceInterfacePrivate::applyState(SurfaceState *next)
 {
     const bool bufferChanged = next->bufferIsSet;
     const bool opaqueRegionChanged = next->opaqueIsSet;
     const bool scaleFactorChanged = next->bufferScaleIsSet && (current.bufferScale != next->bufferScale);
     const bool transformChanged = next->bufferTransformIsSet && (current.bufferTransform != next->bufferTransform);
     const bool shadowChanged = next->shadowIsSet;
     const bool blurChanged = next->blurIsSet;
     const bool contrastChanged = next->contrastIsSet;
     const bool slideChanged = next->slideIsSet;
     const bool childrenChanged = next->childrenChanged;
     const bool visibilityChanged = bufferChanged && bool(current.buffer) != bool(next->buffer);
 
     const QSizeF oldSurfaceSize = surfaceSize;
     const QSize oldBufferSize = bufferSize;
     const QMatrix4x4 oldSurfaceToBufferMatrix = surfaceToBufferMatrix;
     const QRegion oldInputRegion = inputRegion;
 
     next->mergeInto(&current);
     scaleOverride = pendingScaleOverride;
 
     if (lockedPointer) {
         auto lockedPointerPrivate = LockedPointerV1InterfacePrivate::get(lockedPointer);
         lockedPointerPrivate->commit();
     }
     if (confinedPointer) {
         auto confinedPointerPrivate = ConfinedPointerV1InterfacePrivate::get(confinedPointer);
         confinedPointerPrivate->commit();
     }
 
     if (bufferRef != current.buffer) {
         if (bufferRef) {
             bufferRef->unref();
         }
         bufferRef = current.buffer;
         if (bufferRef) {
             bufferRef->ref();
         }
     }
 
     // TODO: Refactor the state management code because it gets more clumsy.
     if (current.buffer) {
         bufferSize = current.buffer->size();
 
         implicitSurfaceSize = current.buffer->size() / current.bufferScale;
         switch (current.bufferTransform) {
         case KWin::Output::Transform::Rotated90:
         case KWin::Output::Transform::Rotated270:
         case KWin::Output::Transform::Flipped90:
         case KWin::Output::Transform::Flipped270:
             implicitSurfaceSize.transpose();
             break;
         case KWin::Output::Transform::Normal:
         case KWin::Output::Transform::Rotated180:
         case KWin::Output::Transform::Flipped:
         case KWin::Output::Transform::Flipped180:
             break;
         }
 
         if (current.viewport.destinationSize.isValid()) {
             surfaceSize = current.viewport.destinationSize;
         } else if (current.viewport.sourceGeometry.isValid()) {
             surfaceSize = current.viewport.sourceGeometry.size().toSize();
         } else {
             surfaceSize = implicitSurfaceSize;
         }
 
         const QRectF surfaceRect(QPoint(0, 0), surfaceSize);
         inputRegion = current.input & surfaceRect.toAlignedRect();
 
         if (!current.buffer->hasAlphaChannel()) {
             opaqueRegion = surfaceRect.toAlignedRect();
         } else {
             opaqueRegion = current.opaque & surfaceRect.toAlignedRect();
         }
 
         QMatrix4x4 scaleOverrideMatrix;
         if (scaleOverride != 1.) {
             scaleOverrideMatrix.scale(1. / scaleOverride, 1. / scaleOverride);
         }
 
         opaqueRegion = map_helper(scaleOverrideMatrix, opaqueRegion);
         inputRegion = map_helper(scaleOverrideMatrix, inputRegion);
         surfaceSize = surfaceSize / scaleOverride;
         implicitSurfaceSize = implicitSurfaceSize / scaleOverride;
     } else {
         surfaceSize = QSizeF(0, 0);
         implicitSurfaceSize = QSizeF(0, 0);
         bufferSize = QSize(0, 0);
         inputRegion = QRegion();
         opaqueRegion = QRegion();
     }
 
     surfaceToBufferMatrix = buildSurfaceToBufferMatrix();
     bufferToSurfaceMatrix = surfaceToBufferMatrix.inverted();
     if (opaqueRegionChanged) {
         Q_EMIT q->opaqueChanged(opaqueRegion);
     }
     if (oldInputRegion != inputRegion) {
         Q_EMIT q->inputChanged(inputRegion);
     }
     if (scaleFactorChanged) {
         Q_EMIT q->bufferScaleChanged(current.bufferScale);
     }
     if (transformChanged) {
         Q_EMIT q->bufferTransformChanged(current.bufferTransform);
     }
     if (visibilityChanged) {
         updateEffectiveMapped();
     }
     if (bufferChanged) {
         if (current.buffer && (!current.damage.isEmpty() || !current.bufferDamage.isEmpty())) {
             const QRegion windowRegion = QRegion(0, 0, q->size().width(), q->size().height());
             const QRegion bufferDamage = q->mapFromBuffer(current.bufferDamage);
             current.damage = windowRegion.intersected(current.damage.united(bufferDamage));
             Q_EMIT q->damaged(current.damage);
         }
     }
     if (surfaceToBufferMatrix != oldSurfaceToBufferMatrix) {
         Q_EMIT q->surfaceToBufferMatrixChanged();
     }
     if (bufferSize != oldBufferSize) {
         Q_EMIT q->bufferSizeChanged();
     }
     if (surfaceSize != oldSurfaceSize) {
         Q_EMIT q->sizeChanged();
     }
     if (shadowChanged) {
         Q_EMIT q->shadowChanged();
     }
     if (blurChanged) {
         Q_EMIT q->blurChanged();
     }
     if (contrastChanged) {
         Q_EMIT q->contrastChanged();
     }
     if (slideChanged) {
         Q_EMIT q->slideOnShowHideChanged();
     }
     if (childrenChanged) {
         Q_EMIT q->childSubSurfacesChanged();
     }
     // The position of a sub-surface is applied when its parent is committed.
     for (SubSurfaceInterface *subsurface : std::as_const(current.below)) {
         auto subsurfacePrivate = SubSurfaceInterfacePrivate::get(subsurface);
         subsurfacePrivate->parentCommit();
     }
     for (SubSurfaceInterface *subsurface : std::as_const(current.above)) {
         auto subsurfacePrivate = SubSurfaceInterfacePrivate::get(subsurface);
         subsurfacePrivate->parentCommit();
     }
     if (role) {
         role->commit();
     }
     Q_EMIT q->committed();
 }
 
 void SurfaceInterfacePrivate::commitSubSurface()
 {
     if (subSurface->isSynchronized()) {
         commitToCache();
     } else {
         if (hasCacheState) {
             commitToCache();
             commitFromCache();
         } else {
             applyState(&pending);
         }
     }
 }
 
 void SurfaceInterfacePrivate::commitToCache()
 {
     pending.mergeInto(&cached);
     hasCacheState = true;
 }
 
 void SurfaceInterfacePrivate::commitFromCache()
 {
     applyState(&cached);
     hasCacheState = false;
 }
 
 bool SurfaceInterfacePrivate::computeEffectiveMapped() const
 {
     if (!bufferRef) {
         return false;
     }
     if (subSurface) {
         return subSurface->parentSurface() && subSurface->parentSurface()->isMapped();
     }
     return true;
 }
 
 void SurfaceInterfacePrivate::updateEffectiveMapped()
 {
     const bool effectiveMapped = computeEffectiveMapped();
     if (mapped == effectiveMapped) {
         return;
     }
 
     mapped = effectiveMapped;
 
     if (mapped) {
         Q_EMIT q->mapped();
     } else {
         Q_EMIT q->unmapped();
     }
 
     for (SubSurfaceInterface *subsurface : std::as_const(current.below)) {
         auto surfacePrivate = SurfaceInterfacePrivate::get(subsurface->surface());
         surfacePrivate->updateEffectiveMapped();
     }
     for (SubSurfaceInterface *subsurface : std::as_const(current.above)) {
         auto surfacePrivate = SurfaceInterfacePrivate::get(subsurface->surface());
         surfacePrivate->updateEffectiveMapped();
     }
 }
 
 bool SurfaceInterfacePrivate::contains(const QPointF &position) const
 {
     // avoid QRectF::contains as that includes all edges
     const qreal x = position.x();
     const qreal y = position.y();
 
     return mapped && x >= 0 && y >= 0 && x < surfaceSize.width() && y < surfaceSize.height();
 }
 
 bool SurfaceInterfacePrivate::inputContains(const QPointF &position) const
 {
     return contains(position) && inputRegion.contains(QPoint(std::floor(position.x()), std::floor(position.y())));
 }
 
 QRegion SurfaceInterface::damage() const
 {
     return d->current.damage;
 }
 
 QRegion SurfaceInterface::opaque() const
 {
     return d->opaqueRegion;
 }
 
 QRegion SurfaceInterface::input() const
 {
     return d->inputRegion;
 }
 
 qint32 SurfaceInterface::bufferScale() const
 {
     return d->current.bufferScale;
 }
 
 KWin::Output::Transform SurfaceInterface::bufferTransform() const
 {
     return d->current.bufferTransform;
 }
 
 ClientBuffer *SurfaceInterface::buffer() const
 {
     return d->bufferRef;
 }
 
 QPoint SurfaceInterface::offset() const
 {
     return d->current.offset / d->scaleOverride;
 }
 
 SurfaceInterface *SurfaceInterface::get(wl_resource *native)
 {
     if (auto surfacePrivate = resource_cast<SurfaceInterfacePrivate *>(native)) {
         return surfacePrivate->q;
     }
     return nullptr;
 }
 
 SurfaceInterface *SurfaceInterface::get(quint32 id, const ClientConnection *client)
 {
     if (client) {
         return get(client->getResource(id));
     }
     return nullptr;
 }
 
 QList<SubSurfaceInterface *> SurfaceInterface::below() const
 {
     return d->current.below;
 }
 
 QList<SubSurfaceInterface *> SurfaceInterface::above() const
 {
     return d->current.above;
 }
 
 SubSurfaceInterface *SurfaceInterface::subSurface() const
 {
     return d->subSurface;
 }
 
 QSizeF SurfaceInterface::size() const
 {
     return d->surfaceSize;
 }
 
 QRectF SurfaceInterface::boundingRect() const
 {
     QRectF rect(QPoint(0, 0), size());
 
     for (const SubSurfaceInterface *subSurface : std::as_const(d->current.below)) {
         const SurfaceInterface *childSurface = subSurface->surface();
         rect |= childSurface->boundingRect().translated(subSurface->position());
     }
     for (const SubSurfaceInterface *subSurface : std::as_const(d->current.above)) {
         const SurfaceInterface *childSurface = subSurface->surface();
         rect |= childSurface->boundingRect().translated(subSurface->position());
     }
 
     return rect;
 }
 
 QPointer<ShadowInterface> SurfaceInterface::shadow() const
 {
     return d->current.shadow;
 }
 
 QPointer<BlurInterface> SurfaceInterface::blur() const
 {
     return d->current.blur;
 }
 
 QPointer<ContrastInterface> SurfaceInterface::contrast() const
 {
     return d->current.contrast;
 }
 
 QPointer<SlideInterface> SurfaceInterface::slideOnShowHide() const
 {
     return d->current.slide;
 }
 
 bool SurfaceInterface::isMapped() const
 {
     return d->mapped;
 }
 
 QVector<OutputInterface *> SurfaceInterface::outputs() const
 {
     return d->outputs;
 }
 
 void SurfaceInterface::setOutputs(const QVector<OutputInterface *> &outputs)
 {
     QVector<OutputInterface *> removedOutputs = d->outputs;
     for (auto it = outputs.constBegin(), end = outputs.constEnd(); it != end; ++it) {
         const auto o = *it;
         removedOutputs.removeOne(o);
     }
     for (auto it = removedOutputs.constBegin(), end = removedOutputs.constEnd(); it != end; ++it) {
         const auto resources = (*it)->clientResources(client());
         for (wl_resource *outputResource : resources) {
             d->send_leave(outputResource);
         }
         disconnect(d->outputDestroyedConnections.take(*it));
         disconnect(d->outputBoundConnections.take(*it));
     }
     QVector<OutputInterface *> addedOutputsOutputs = outputs;
     for (auto it = d->outputs.constBegin(), end = d->outputs.constEnd(); it != end; ++it) {
         const auto o = *it;
         addedOutputsOutputs.removeOne(o);
     }
     for (auto it = addedOutputsOutputs.constBegin(), end = addedOutputsOutputs.constEnd(); it != end; ++it) {
         const auto o = *it;
         const auto resources = o->clientResources(client());
         for (wl_resource *outputResource : resources) {
             d->send_enter(outputResource);
         }
         d->outputDestroyedConnections[o] = connect(o, &OutputInterface::removed, this, [this, o] {
             auto outputs = d->outputs;
             if (outputs.removeOne(o)) {
                 setOutputs(outputs);
             }
         });
 
         Q_ASSERT(!d->outputBoundConnections.contains(o));
         d->outputBoundConnections[o] = connect(o, &OutputInterface::bound, this, [this](ClientConnection *c, wl_resource *outputResource) {
             if (c != client()) {
                 return;
             }
             d->send_enter(outputResource);
         });
     }
 
     d->outputs = outputs;
     for (auto child : std::as_const(d->current.below)) {
         child->surface()->setOutputs(outputs);
     }
     for (auto child : std::as_const(d->current.above)) {
         child->surface()->setOutputs(outputs);
     }
 }
 
 SurfaceInterface *SurfaceInterface::surfaceAt(const QPointF &position)
 {
     if (!isMapped()) {
         return nullptr;
     }
 
     for (auto it = d->current.above.crbegin(); it != d->current.above.crend(); ++it) {
         const SubSurfaceInterface *current = *it;
         SurfaceInterface *surface = current->surface();
         if (auto s = surface->surfaceAt(position - current->position())) {
             return s;
         }
     }
 
     // check whether the geometry contains the pos
     if (d->contains(position)) {
         return this;
     }
 
     for (auto it = d->current.below.crbegin(); it != d->current.below.crend(); ++it) {
         const SubSurfaceInterface *current = *it;
         SurfaceInterface *surface = current->surface();
         if (auto s = surface->surfaceAt(position - current->position())) {
             return s;
         }
     }
     return nullptr;
 }
 
 SurfaceInterface *SurfaceInterface::inputSurfaceAt(const QPointF &position)
 {
     // TODO: Most of this is very similar to SurfaceInterface::surfaceAt
     //       Is there a way to reduce the code duplication?
     if (!isMapped()) {
         return nullptr;
     }
 
     for (auto it = d->current.above.crbegin(); it != d->current.above.crend(); ++it) {
         const SubSurfaceInterface *current = *it;
         auto surface = current->surface();
         if (auto s = surface->inputSurfaceAt(position - current->position())) {
             return s;
         }
     }
 
     // check whether the geometry and input region contain the pos
     if (d->inputContains(position)) {
         return this;
     }
 
     for (auto it = d->current.below.crbegin(); it != d->current.below.crend(); ++it) {
         const SubSurfaceInterface *current = *it;
         auto surface = current->surface();
         if (auto s = surface->inputSurfaceAt(position - current->position())) {
             return s;
         }
     }
 
     return nullptr;
 }
 
 LockedPointerV1Interface *SurfaceInterface::lockedPointer() const
 {
     return d->lockedPointer;
 }
 
 ConfinedPointerV1Interface *SurfaceInterface::confinedPointer() const
 {
     return d->confinedPointer;
 }
 
 bool SurfaceInterface::inhibitsIdle() const
 {
     return !d->idleInhibitors.isEmpty();
 }
 
 LinuxDmaBufV1Feedback *SurfaceInterface::dmabufFeedbackV1() const
 {
     return d->dmabufFeedbackV1.get();
 }
 
 KWin::ContentType SurfaceInterface::contentType() const
 {
     return d->current.contentType;
 }
 
 QPointF SurfaceInterface::mapToBuffer(const QPointF &point) const
 {
     return d->surfaceToBufferMatrix.map(point);
 }
 
 QPointF SurfaceInterface::mapFromBuffer(const QPointF &point) const
 {
     return d->bufferToSurfaceMatrix.map(point);
 }
 
 QRegion SurfaceInterface::mapToBuffer(const QRegion &region) const
 {
     return map_helper(d->surfaceToBufferMatrix, region);
 }
 
 QRegion SurfaceInterface::mapFromBuffer(const QRegion &region) const
 {
     return map_helper(d->bufferToSurfaceMatrix, region);
 }
 
 QMatrix4x4 SurfaceInterface::surfaceToBufferMatrix() const
 {
     return d->surfaceToBufferMatrix;
 }
 
 QPointF SurfaceInterface::mapToChild(SurfaceInterface *child, const QPointF &point) const
 {
     QPointF local = point;
     SurfaceInterface *surface = child;
 
     while (true) {
         if (surface == this) {
             return local;
         }
 
         SubSurfaceInterface *subsurface = surface->subSurface();
         if (Q_UNLIKELY(!subsurface)) {
             return QPointF();
         }
 
         local -= subsurface->position();
         surface = subsurface->parentSurface();
     }
 
     return QPointF();
 }
 
 QSize SurfaceInterface::bufferSize() const
 {
     return d->bufferSize;
 }
 
 qreal SurfaceInterface::scaleOverride() const
 {
     return d->scaleOverride;
 }
 
 QPoint SurfaceInterface::toSurfaceLocal(const QPoint &point) const
 {
     return QPoint(point.x() * d->scaleOverride, point.y() * d->scaleOverride);
 }
 
 QPointF SurfaceInterface::toSurfaceLocal(const QPointF &point) const
 {
     return QPointF(point.x() * d->scaleOverride, point.y() * d->scaleOverride);
 }
 
 PresentationHint SurfaceInterface::presentationHint() const
 {
     return d->current.presentationHint;
 }
 
 void SurfaceInterface::setPreferredScale(qreal scale)
 {
     if (scale == d->preferredScale) {
         return;
     }
     d->preferredScale = scale;
 
     if (d->fractionalScaleExtension) {
         d->fractionalScaleExtension->setPreferredScale(scale);
     }
     for (auto child : qAsConst(d->current.below)) {
         child->surface()->setPreferredScale(scale);
     }
     for (auto child : qAsConst(d->current.above)) {
         child->surface()->setPreferredScale(scale);
     }
 }
 
 } // namespace KWaylandServer