Qt 5.8 | Qt Data Visualization | Custom Items Example

Qt 5.8.0 Reference Documentation

# Custom Items Example

The custom items example shows how to add your own custom meshes as items to a graph, and how to remove them.

## Running the Example

To run the example from Qt Creator, open the Welcome mode and select the example from Examples. For more information, visit Building and Running an Example.

## Adding Custom Meshes to the Application

We'll add the meshes in a resource file:

      <RCC>
      ...
      <qresource prefix="/items">
          <file>refinery.obj</file>
          <file>oilrig.obj</file>
      </qresource>
      </RCC>

## Adding Custom Item to a Graph

In this example we do not have specific textures for our meshes, so we'll just create a small QImage and fill it with a single color:

      QImage color = QImage(2, 2, QImage::Format_RGB32);
      color.fill(Qt::red);

Then we'll specify the position for the item in a variable. This way we'll be able to use it later for removing the correct item:

      QVector3D positionOne = QVector3D(39.0f, 77.0f, 19.2f);

Then we'll create a new QCustom3DItem with all the parameters:

      QCustom3DItem *item = new QCustom3DItem(":/items/oilrig.obj", positionOne,
                                              QVector3D(0.025f, 0.025f, 0.025f),
                                              QQuaternion::fromAxisAndAngle(0.0f, 1.0f, 0.0f, 45.0f),
                                              color);

And finally we'll just add the item:

      m_graph->addCustomItem(item);

## Removing Custom Item from a Graph

We'll just call `removeCustomItemAt()` with the position of the item:

      m_graph->removeCustomItemAt(positionOne);

Note: Removing a custom item from the graph also deletes it. If you want to preserve the item, you need to use `releaseCustomItem()` method instead.

## Example Contents

Files:

- customitems/customitemgraph.cpp
- customitems/customitemgraph.h
- customitems/main.cpp
- customitems/customitems.pro
- customitems/customitems.qrc