Revision control
+ // Copyright (C) 2026 The Qt Company Ltd.
+ // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only
+
+ // Takes the scene away from the world from inside a trigger report, while the
+ // batch of reports that carries it is still on the stack. Moving the world
+ // deregisters every body at once, which is what deleting one does to the
+ // trigger callback's end of things, and it lands while the callback is still
+ // running rather than whenever the object a delete was asked for is deferred
+ // to. Deregistering from there took the lock the callback held, on the thread
+ // that already held it, so the application hung. Reaching the next frame is
+ // the assertion.
+ //
+ // Three bodies cross the boundary together, so the report the world is moved
+ // from is one of a batch and the pairs behind it are about bodies the move has
+ // taken out. Only the first is reported: the rest are asked about one at a
+ // time and skipped.
+ //
+ // No rendering is needed for any of this, so scene is a plain Node rather than
+ // a View3D.
+
+ import QtQuick
+ import QtTest
+ import QtQuick3D
+ import QtQuick3D.Physics
+ import QtQuick3D.Physics.TestUtils
+
+ Item {
+ id: root
+ width: 64
+ height: 64
+
+ // The frame the world was moved on, set by the first report to arrive.
+ property int frameAtMove: -1
+ property int reports: 0
+
+ PhysicsWorld {
+ id: world
+ gravity: Qt.vector3d(0, -981, 0)
+ running: true
+ typicalLength: 100
+ typicalSpeed: 1000
+ minimumTimestep: 15
+ maximumTimestep: 15
+ scene: fallingScene
+
+ property int frameCount: 0
+ onFrameDone: world.frameCount++
+ }
+
+ Node {
+ id: fallingScene
+
+ TriggerBody {
+ id: gate
+ collisionShapes: BoxShape {
+ extents: Qt.vector3d(400, 100, 100)
+ }
+
+ onBodyEntered: (body) => {
+ root.reports++;
+ if (root.frameAtMove < 0) {
+ root.frameAtMove = world.frameCount;
+ world.scene = elsewhere;
+ }
+ }
+ }
+
+ // Side by side and let go of from the same height, so they reach the
+ // trigger on the same step and the pairs that say so arrive together.
+ Repeater3D {
+ model: 3
+ DynamicRigidBody {
+ required property int index
+ position: Qt.vector3d(index * 120 - 120, 200, 0)
+ sendTriggerReports: true
+ collisionShapes: BoxShape {
+ extents: Qt.vector3d(50, 50, 50)
+ }
+ }
+ }
+ }
+
+ // What the world is moved to. It holds no bodies, so the move leaves every
+ // body without a world rather than handing it to a new one.
+ Node {
+ id: elsewhere
+ }
+
+ PhysicsTestCase {
+ name: "moving the world from a trigger report reaches the next frame"
+ timeoutSecs: 10
+ goalReached: root.frameAtMove >= 0 && world.frameCount > root.frameAtMove + 1
+ }
+
+ PhysicsTestCase {
+ name: "a body the move took out is not reported"
+ timeoutSecs: 10
+ goalReached: root.frameAtMove >= 0 && world.frameCount > root.frameAtMove + 1
+ && root.reports === 1
+ }
+ }