phdvrphdvr by peter houska directvolumerendererdirectvolumerenderer
Post on 22-Dec-2015
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PHDVR
by Peter Houska
direct
volume
renderer
CUBERILLE
sample at grid-locations only
scan each voxel along ray exactly once
"3D-DDA" instead of actually performing an explicit intersection-calculation with each "voxel-cube"/cell
nearest-neighbor interpolation (rounding by truncation) yields "cube-look"
CUTTING PLANES / -SPHERES
Intuitive 3D-Interface for placing the cutting-plane and cutting-sphere, respectively.
PRECOMPUTED "3D - SHADOWMAPS"
Preprocessed occlusion-data32-bit per voxel with bits 31-16 for "occlusion-factor" so no big performance hit through additional mem-accesses to a 2nd bufferJust one additional lookup (+2 mutiplies) during rendering for each voxel that needs to be drawn along each rayShadow-map gets invalidated, when lightsource moves or transfer-function is altered considerably
BINARY CLASSIFIED (CRISP)"MULTI"-ISOSURFACES
Perform usual scan-steps as long as "sampled density" < "desired isovalue"Employ binary search in the area of interest to increase accuracy
TOONSHADING / EDGE DETECTIONZ-Buffer is generated at no additional cost during ray-castingProcess z-buffer as if it was a 2D-image (with horizontal and vertical edge-detector filters)Blend edges that were found with ray-casted color-informations
PENCIL SKETCH SHADING
RBS / ICS