View overview
The View provides a render area to enable visualization of the
current model data and overlay items.
Each view observes one or more Model and is associated with a Camera
and a Viewer. The Camera represents how the
model is viewed while the Viewer class represents the connection with a computer windowing system.
Models
A view can contain one or more models to be visualized. A model is the visual setup of your data being either
an UnstructGridModel, a MarkupModel or
a GeometryModel
See the Model topic for a description of the different model types.
Camera
The camera provides support for camera manipulation in the view. You can use a built-in input handler or create your own customized input handler by sub classing cee::vis::CameraInputHandler. The camera enables both perspective (field of view and clipping planes) and parallel projection. It offers useful features such as support for rubberband zooming and extracting a ray from windows coordinates to be used for, for example, picking.
Each view has its own camera object.
Overlay items
The view can have any number of overlay items. These are items drawn on top of the model in the view, for instance a color legend for scalar results.
Available overlay item types are:
Overlay items are added to a corner of your choosing using Overlay::addItem(). Or, if you want
full control over the overlay layout, you can add the overlay item using LayoutDirection::ABSOLUTE_POSITION
and use OverlayItem::setAbsolutePosition().
Clipping
Clipping planes are used to clip parts of the geometry in the scene to be able to look inside. Anything behind (on the opposite side of the plane normal) the given planes is hidden.
CEETRON Envision supports bounded clipping planes. This allows for cutting out parts of
the model in many different ways. Normal clipping planes will clip an object/fragment if
it is on the wrong side of any of the active clipping planes.
By default an object/fragment will be clipped if it is behind (on the opposite side of the plane normal)
at least one of the specified planes. Setting setMustBeBehindAllPlanesToClip()
to true will require that an object/fragment be behind all the specified planes in order to be clipped.
Background
The view’s background settings. The background can either be single colored or a gradient between a top and a bottom color.
Image rendering
The current view can be exported to an image as a cee::Image object. The cee::Image is a simple structure containing raw RGBA image data and can be easily read from any image exporter tool. CEETRON Envision offer the helper classes cee::ImageIoPng and cee::ImageIoJpeg to convert cee::Image into PNG and JPEG files.
Bounding box
The bounding box of all currently visible models can be found using boundingBox().
