The Visualisation Manager

Introduction

The visualisation manager is responsible for managing graphical plugins and handling the 3D context (currently based on Ogre3D).

In the Designer tool, graphical plugins may be arranged in space in a very flexible way. In a given scenario, each plugin may be displayed in its own window, or several plugins may be fitted in a single window using tabs and horizontal/vertical splits. This arrangement is stored in visualisation trees made up of visualisation widgets. The visualisation manager owns a list of these visualisation trees.

3D rendering is an important feature of the platform. It is handled by the visualisation manager, which initializes a 3d context at startup and then creates 3D widgets as required by scenarios when they are run. Resource management is also taken care of by this manager, allowing for dynamic creation and destruction of groups of resources by applications and plugins.

Layout management

The arrangement in space of graphical plugins is handled by CVisualisationTree objects.

3D API

One of the key features of the platform is its range of visualisation paradigms, from simple 2D signal displays to 3D topographic mapping and more. The use of 3D may facilitate brain activity visualisation, and can also make BCI experiments more attractive to users. However, OpenViBE doesn't aim at handling very complex 3D scenes. Anyone wanting to test a BCI to e.g. navigate through a large 3D world should rather consider using OpenViBE as a peripheral to interact with an external 3D application dedicated to handling the 3d world.

A simplified 3D API is available to plugins for

visualisation_manager_3D_objects

Frame : Y up, looking down Z axis

Objects : should be exported to Ogre's .mesh format. For objects which vertex colors will be modified, the vertex buffer should have the "dynamic" property (the index buffer may be left with the default "static" property since it will probably only be read once).