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Ray Tracing Visualization of Sphere Constrained Flow

Simulation: flow constrained to the surface of a sphere modeled using Galerkin-Boltzmann equations (Tölke et al '00) discretized with a tenth order discontinuous Galerkin spectral elements in space and adaptive semi-analytic Runge-Kutta time stepping. See this arXiv preprint for background on the flow simulation techniques. All computations performed on a single NVIDIA V100 GPU. Post-processing: magnitude of vorticity rendered with Whitted style ray-tracing also performed on the GPU using the simpleRayTracer developed by the Paranumal group at Virginia Tech. At the moment the scene is rendered using CUDA. We plan to port the implementation to OCCA and eventually to exploit the ray tracing

3D ellipsoids: rendering and collision detection

Added ellipsoids to the set of objects supported by the simple Whitted style ray tracer [1] we developed for the CMDA 3634 course @Virginia Tech for Fall 2018. To detect collisions between sphere and ellipsoids we use a Newton based algorithm for finding the nearest point on an ellipsoid to another point from Robert Nümberg using his notes. Remarkably it appears to have worked perfectly first time! [1] Whitted, T., 1979, August. An improved illumination model for shaded display. In ACM SIGGRAPH Computer Graphics (Vol. 13, No. 2, p. 14). ACM.

Adding Object Motion to the Paranumal Accelerated Ray Tracer

Capabilities of the Paranumal Accelerated Ray Tracer: Whitted based ray transport (link). Stack based multiple scattering. GPU acceleration. Primitives: spheres, cylinders, cones, planes, triangles, disks. Field of view emulated using Monte Carlo ray casting through thin lens. Reflective or refractive objects. Demoed here with simple collision dynamics. Tutorial: link. Reference: Whitted, T., 2005, July. An improved illumination model for shaded display. In ACM Siggraph 2005 Courses (p. 4). ACM.


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