[vtk-developers] New feature: improved hover support

Jeff Baumes jeff.baumes at kitware.com
Wed Sep 9 11:04:31 EDT 2009

I've just checked in a change that allows improved hover support in
vtkRenderView subclasses.
After each render (except during interaction), the view automatically takes
a "snapshot" of what is currently rendered in a special render mode that
maps pixel locations particular actors and cells. When the user's mouse
stops over a cell, the render view looks up the hovered cell in the map and
sends it to its representations to possibly produce a hover label.
Representations manage the pipleline/mappers/actors for displaying a
particular type of data in a view. They implement support for hover queries
by overriding GetHoverTextInternal().

This is currently implemented in vtkRenderedGraphRepresentation, where the
user may select the vertex and edge hover arrays.

The view also allows the hover labels not to be rendered with OpenGL, but
invokes a HoverEvent when the hover label changes. This would allow an
application to capture these events and use real native tooltips (e.g. with
Qt) to show the hover labels.

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://public.kitware.com/pipermail/vtk-developers/attachments/20090909/2630ae85/attachment.html>

More information about the vtk-developers mailing list