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// Copyright (C) 2022 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only
// Qt-Security score:significant reason:default
#include "instancerepeater_p.h"
#include <math.h>
#include <QMatrix4x4>
QT_BEGIN_NAMESPACE
/*!
\qmltype InstanceModel
\inherits Object3D
\inqmlmodule QtQuick3D.Helpers
\since 6.4
\brief Defines a data model based on an instance table.
The InstanceModel QML type is a data model that provides access to the elements of an \l Instancing table.
The following roles are available:
\table
\header
\li Role name
\li Description
\row
\li \c modelPosition
\li The position of the instance as a \l vector3d
\row
\li \c modelRotation
\li The rotation of the instance as a \l quaternion
\row
\li \c modelScale
\li The scale of the instance as a \l vector3d
\row
\li \c modelColor
\li The \l color of the instance
\row
\li \c modelData
\li The custom data of the instance as a \l vector4d
\endtable
\sa InstanceRepeater
*/
/*!
\qmlproperty Instancing InstanceModel::instancingTable
This property specifies the underlying instance table of the model.
*/
InstanceModel::InstanceModel(QObject *parent)
: QAbstractListModel(parent)
{
}
QVariant InstanceModel::data(const QModelIndex &index, int role) const
{
if (!index.isValid())
return QVariant();
ensureTable();
int idx = index.row();
if (idx >= m_count) {
qWarning("InstanceModel: index out of range");
return QVariant();
}
auto *instanceData = reinterpret_cast<const QQuick3DInstancing::InstanceTableEntry*>(m_instanceData.data()) + idx;
switch (role) {
case ColorRole:
return instanceData->getColor();
case PositionRole:
return instanceData->getPosition();
case RotationRole:
return instanceData->getRotation();
case ScaleRole:
return instanceData->getScale();
case CustomDataRole:
return instanceData->instanceData;
}
return QVariant();
}
int InstanceModel::rowCount(const QModelIndex &) const
{
ensureTable();
return m_count;
}
void InstanceModel::setInstancing(QQuick3DInstancing *instancing)
{
if (m_instancing == instancing)
return;
QObject::disconnect(m_tableConnection);
m_instancing = instancing;
m_tableConnection = QObject::connect(instancing, &QQuick3DInstancing::instanceTableChanged, this, &InstanceModel::reset);
emit instancingChanged();
}
const QQuick3DInstancing::InstanceTableEntry *InstanceModel::instanceData(int index) const
{
if (index >= m_count)
return nullptr;
return reinterpret_cast<const QQuick3DInstancing::InstanceTableEntry*>(m_instanceData.constData()) + index;
}
void InstanceModel::ensureTable() const
{
auto *that = const_cast<InstanceModel*>(this);
that->m_instanceData = m_instancing->instanceBuffer(&that->m_count);
}
void InstanceModel::reset()
{
beginResetModel();
m_instanceData.clear();
endResetModel();
}
/*!
\qmltype InstanceRepeater
\inherits Repeater3D
\inqmlmodule QtQuick3D.Helpers
\since 6.4
\brief Instantiates components based on an instance table.
The InstanceRepeater type is used to create a number of objects based on an
\l Instancing table. It is a \l Repeater3D subtype that takes an Instancing table instead
of a data model, and automatically applies \c position, \c scale, and \c rotation.
One use case is to implement \l {View3D::pick}{picking} by creating invisible dummy objects
that match the rendered instances. To improve performance, the dummy objects can be created with a
simpler geometry than the instanced models.
For example:
\qml
InstanceRepeater {
instancingTable: myInstanceTable
Model {
source: "#Cube"
pickable: true
property int instanceIndex: index // expose the index, so we can identify the instance
opacity: 0
}
}
\endqml
\sa InstanceModel
*/
/*!
\qmlproperty Instancing InstanceRepeater::instancingTable
This property specifies the instance table used by the repeater.
*/
InstanceRepeater::InstanceRepeater(QQuick3DNode *parent)
: QQuick3DRepeater(parent)
{
}
QQuick3DInstancing *InstanceRepeater::instancing() const
{
return m_model ? m_model->instancing() : nullptr;
}
void InstanceRepeater::setInstancing(QQuick3DInstancing *instancing)
{
if (m_model && m_model->instancing() == instancing)
return;
if (!m_model)
m_model = new InstanceModel(this);
m_model->setInstancing(instancing);
setModel(QVariant::fromValue(m_model));
emit instancingChanged();
}
void InstanceRepeater::initDelegate(int index, QQuick3DNode *node)
{
Q_ASSERT(m_model);
auto *entry = m_model->instanceData(index);
Q_ASSERT(entry);
node->setPosition(entry->getPosition());
node->setScale(entry->getScale());
node->setRotation(entry->getRotation());
}
QT_END_NAMESPACE