QmlDesigner: Fix selection box size calculations

Selection box for zero size items ended up being infinite, which broke
some functionality like fit to camera. Now boxes should be correctly
zero sized for non-model items. This also fixes issues with parent
box size if it has zero size children.

Change-Id: I3c8fae3ee971fbb0cf9e0de2615c107ce97a76f8
Fixes: QDS-1287
Reviewed-by: Mahmoud Badri <mahmoud.badri@qt.io>
Reviewed-by: Thomas Hartmann <thomas.hartmann@qt.io>

2 files changed, 21 insertions, 5 deletions

diff --git a/share/qtcreator/qml/qmlpuppet/qml2puppet/editor3d/generalhelper.cpp b/share/qtcreator/qml/qmlpuppet/qml2puppet/editor3d/generalhelper.cpp
index 150b8e9ab1..84e28ac4ec 100644
--- a/share/qtcreator/qml/qmlpuppet/qml2puppet/editor3d/generalhelper.cpp
+++ b/share/qtcreator/qml/qmlpuppet/qml2puppet/editor3d/generalhelper.cpp
@@ -149,7 +149,8 @@ QVector4D GeneralHelper::focusObjectToCamera(QQuick3DCamera *camera, float defau
     QVector3D lookAt = targetObject ? targetObject->scenePosition() : QVector3D();
 
     // Get object bounds
-    qreal maxExtent = 200.;
+    const qreal defaultExtent = 200.;
+    qreal maxExtent = defaultExtent;
     if (auto modelNode = qobject_cast<QQuick3DModel *>(targetObject)) {
         auto targetPriv = QQuick3DObjectPrivate::get(targetObject);
         if (auto renderModel = static_cast<QSSGRenderModel *>(targetPriv->spatialNode)) {
@@ -173,6 +174,9 @@ QVector4D GeneralHelper::focusObjectToCamera(QQuick3DCamera *camera, float defau
                     maxExtent = qSqrt(qreal(e.x() * e.x() + e.y() * e.y() + e.z() * e.z()));
                     maxExtent *= maxScale;
 
+                    if (maxExtent < 0.0001)
+                        maxExtent = defaultExtent;
+
                     // Adjust lookAt to look directly at the center of the object bounds
                     lookAt = renderModel->globalTransform.map(center);
                     lookAt.setZ(-lookAt.z()); // Render node transforms have inverted z
diff --git a/share/qtcreator/qml/qmlpuppet/qml2puppet/editor3d/selectionboxgeometry.cpp b/share/qtcreator/qml/qmlpuppet/qml2puppet/editor3d/selectionboxgeometry.cpp
index 1fb4f445a6..17b101326e 100644
--- a/share/qtcreator/qml/qmlpuppet/qml2puppet/editor3d/selectionboxgeometry.cpp
+++ b/share/qtcreator/qml/qmlpuppet/qml2puppet/editor3d/selectionboxgeometry.cpp
@@ -43,6 +43,8 @@ namespace Internal {
 
 static const float floatMin = std::numeric_limits<float>::lowest();
 static const float floatMax = std::numeric_limits<float>::max();
+static const QVector3D maxVec = QVector3D(floatMax, floatMax, floatMax);
+static const QVector3D minVec = QVector3D(floatMin, floatMin, floatMin);
 
 SelectionBoxGeometry::SelectionBoxGeometry()
     : QQuick3DGeometry()
@@ -136,8 +138,8 @@ QSSGRenderGraphObject *SelectionBoxGeometry::updateSpatialNode(QSSGRenderGraphOb
     QByteArray vertexData;
     QByteArray indexData;
 
-    QVector3D minBounds = QVector3D(floatMax, floatMax, floatMax);
-    QVector3D maxBounds = QVector3D(floatMin, floatMin, floatMin);
+    QVector3D minBounds = maxVec;
+    QVector3D maxBounds = minVec;
 
     if (m_targetNode) {
         auto rootPriv = QQuick3DObjectPrivate::get(m_rootNode);
@@ -165,6 +167,8 @@ QSSGRenderGraphObject *SelectionBoxGeometry::updateSpatialNode(QSSGRenderGraphOb
         }
     } else {
         // Fill some dummy data so geometry won't get rejected
+        minBounds = {};
+        maxBounds = {};
         appendVertexData(QMatrix4x4(), vertexData, indexData, minBounds, maxBounds);
     }
 
@@ -207,8 +211,8 @@ void SelectionBoxGeometry::getBounds(
         trackNodeChanges(node);
     }
 
-    QVector3D localMinBounds = QVector3D(floatMax, floatMax, floatMax);
-    QVector3D localMaxBounds = QVector3D(floatMin, floatMin, floatMin);
+    QVector3D localMinBounds = maxVec;
+    QVector3D localMaxBounds = minVec;
 
     // Find bounds for children
     QVector<QVector3D> minBoundsVec;
@@ -277,6 +281,14 @@ void SelectionBoxGeometry::getBounds(
                 }
             }
         }
+    } else {
+        combineMinBounds(localMinBounds, {});
+        combineMaxBounds(localMaxBounds, {});
+    }
+
+    if (localMaxBounds == minVec) {
+        localMinBounds = {};
+        localMaxBounds = {};
     }
 
     // Transform local space bounding box to parent space