Voreen 2.5 utilizing OpenGL and GLSL adds support for OpenCL

[Stefan]

The new release of the Voreen 2.5 volume rendering engine contains several new features. It is now possible to create and edit animations, which can be exported as videos. Furthermore, Voreen now contains a GPU-based multi-volume renderer, allows aggregation of subnetworks and supports iterative processing by exploiting loops in the network graph, and contains support for OpenCL used for some processors.

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