24 research outputs found
Hybrid visibility compositing and masking for illustrative rendering
In this paper, we introduce a novel framework for the compositing of interactively rendered 3D layers tailored to the needs of scientific illustration. Currently, traditional scientific illustrations are produced in a series of composition stages, combining different pictorial elements using 2D digital layering. Our approach extends the layer metaphor into 3D without giving up the advantages of 2D methods. The new compositing approach allows for effects such as selective transparency, occlusion overrides, and soft depth buffering. Furthermore, we show how common manipulation techniques such as masking can be integrated into this concept. These tools behave just like in 2D, but their influence extends beyond a single viewpoint. Since the presented approach makes no assumptions about the underlying rendering algorithms, layers can be generated based on polygonal geometry, volumetric data, point-based representations, or others. Our implementation exploits current graphics hardware and permits real-time interaction and rendering.publishedVersio
Visual Parameter Exploration in GPU Shader Space
The wide availability of high-performance GPUs has made the use of shader programs in visualization ubiquitous.
Understanding shaders is a challenging task. Frequently it is difficult to mentally reconstruct the nature and types
of transformations applied to the underlying data during the visualization process. We propose a method for the
visual analysis of GPU shaders, which allows the flexible exploration and investigation of algorithms, parameters,
and their effects. We introduce a method for extracting feature vectors composed of several attributes of the shader,
as well as a direct manipulation interface for assigning semantics to them. The user interactively classifies pixels of
images which are rendered with the investigated shader. The two resulting classes, a positive class and a negative
one, are employed to steer the visualization. Based on this information, we can extract a wide variety of additional
attributes and visualize their relation to this classification. Our system allows an interactive exploration of shader
space and we demonstrate its utility for several different applications