Described is a system, method and computer program product for rendering volumetric multivalued primary data. The system includes a rendering engine having an input coupled to a source of multivalued primary data and an output coupled to a display. The rendering engine includes a data processor for calculating additional data values from the primary data, deriving at least one visual representation from the primary data and the additional data values, and mapping the derived visual representation through transfer functions to hardware primitives for volumetrically rendering the derived visual representation to provide a visualization. The system further includes a user interface for interacting with the visualization. The source of primary data can be a magnetic resonance imaging system, and the primary data may be a multivalued combination obtained from T1 weighted data, T2 weighted data, diffusion data, velocity data, magnetization transfer data, perfusion data, data derived from other imaging modalities (e.g., PET), and simulation data. The primary data can be diffusion tensor data generated by the MRI system from tissue, and the data processor operates to identify directed diffusion paths and to render the directed diffusion paths as thread-like structures. Indications of at least flowing blood velocity and vorticity can also be rendered from MRI data or from simulations.