Use the Scroll View nodes to create an input plane to enable user input from swiping gestures. For example, you can use the scroll message with its parameters generated by a Scroll View node to move a map plane or rotate a mesh.
When you create a Scroll View node it does not have a visual shape and does not necessarily need visible content, but can instead work as an interactive surface. When a user interacts with a Scroll View node, the action generates a message that travels to the Scroll View node where you can define the behavior for that message. See Tutorial: Rotate a 3D model.
The Scroll View: Scrolled message. You can add actions to react to these messages to, for example, set the position of an object according to the scrolling.
reports changes of its scroll position through theNote that Scroll View 3D node has location, position, and size in 3D space. It registers user input in 3D coordinates within the area defined by the size of the Scroll View 3D node. Take this into account when designing interaction with the Scroll View 3D. For example, if you rotate the Scroll View 3D node, the scroll input gets distorted.
To create a scroll view:
Click Save.
In the Preview when you click and drag along the x axis within the Scroll View node, the object you set as the Target Item of the Set Property Value action of the Scroll View: Scrolled message moves according to the settings defined by the Scroll View node.
To test whether the scroll view is working properly, add to the scroll view trigger you are using a Write Log action. Every time you use the scroll view, Kanzi Studio writes a message to the Log window.
Use brushes to set the background of 2D nodes. In Kanzi all 2D nodes by default have transparent background.
To set the background:
This example shows the use of a scroll view as a controller for moving the map plane in a scene. The simplest usage, translating the scroll position coordinates to an object nodes translation attributes is implemented already in the studio project, while more advanced features are created in the program code.
A key aspect in using the scroll view is the controlling of input sensitivity based on the distance of the scroll view plane from the camera. This example uses a one-to-one mapping with the background plane by positioning them at the same distance and orientation from the camera. Scroll view and the background plane, however, are not tied together under the same translation because that way the input coordinate space would move along with the background plane during the user's panning gesture. By positioning the scroll view plane further from the camera, the sensitivity of scroll view gestures increases.
This example demonstrates the use of a raw InterpolatedValue
instance in the program code for afflicting a z-offset (zoom) based on the velocity of the movement.
The scroll view as well as the trajectory list box components manipulate input to output coordinates through a value interpolator, effectively allowing for smoother gesture mappings that are often most suitable for touchscreen based interactions.
You can find the example in <KanziWorkspace>/Examples/Scroll_view.