We present an interactive graphical approach for the explicit specification of semantics for volume visualization. This explicit and graphical specification of semantics for volumetric features allows us to visually assign meaning to both input and output parameters of the visualization mapping. This is in contrast to the implicit way of specifying semantics using transfer functions. In particular, we demonstrate how to realize a dynamic specification of semantics which allows to flexibly explore a wide range of mappings. Our approach is based on three concepts. First, we use semantic shader augmentation to automatically add rule-based rendering functionality to static visualization mappings in a shader program, while preserving the visual abstraction that the initial shader encodes. With this technique we extend recent developments that define a mapping between data attributes and visual attributes with rules, which are evaluated using fuzzy logic. Second, we let users define the semantics by analogy through brushing on renderings of the data attributes of interest. Third, the rules are specified graphically in an interface that provides visual clues for potential modifications. Together, the presented methods offer a high degree of freedom in the specification and exploration of rule-based mappings and avoid the limitations of a linguistic rule formulation.

中文翻译：

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用于说明性体积可视化的类比语义

我们提出了一种交互式图形方法，用于显式规范体积可视化的语义。这种体积特征语义的显式和图形化规范使我们能够直观地为可视化映射的输入和输出参数分配含义。这与使用传递函数指定语义的隐式方式形成对比。特别是，我们演示了如何实现语义的动态规范，允许灵活地探索广泛的映射。我们的方法基于三个概念。首先，我们使用语义着色器增强将基于规则的渲染功能自动添加到着色器程序中的静态可视化映射，同时保留初始着色器编码的视觉抽象。通过这种技术，我们扩展了最近的发展，这些发展定义了数据属性和具有规则的视觉属性之间的映射，这些映射使用模糊逻辑进行评估。其次，我们让用户通过刷上感兴趣的数据属性的渲染来类比定义语义。第三，规则在界面中以图形方式指定，为潜在的修改提供视觉线索。总之，所提出的方法在基于规则的映射的规范和探索方面提供了高度的自由度，并避免了语言规则表述的局限性。这些规则在一个界面中以图形方式指定，为潜在的修改提供视觉线索。总之，所提出的方法在基于规则的映射的规范和探索方面提供了高度的自由，并避免了语言规则公式的局限性。这些规则在一个界面中以图形方式指定，为潜在的修改提供视觉线索。总之，所提出的方法在基于规则的映射的规范和探索方面提供了高度的自由度，并避免了语言规则表述的局限性。