Mixing translucent polygons with volumes

Abstract

Figure 1: Min’ng polygons with mukiple volumes: A scalpel (containing 368 polygons) cutting into a human head (from MRI) while visualizing blood vessels (from an angiogram): (a) translucentpolygons reveal the blood vessels behind the scalpel, (b) opaque rendering obscures potentially dangerous movements (also in color plate). We present an algorithm which renders opaque andor translucent polygons embedded within volumetric data The processing occurs such thai all objects are composited in the correct ordet by ren-dering thin slabs of the translucent polygons between volume slices using slice-order volume rendering. We implemented our algorithm with OpenGL on current general-purpose graphics systems. We dis-cuss our system implementation, speed and image quality, as well as the renderings of several mixed scenes.