In this paper, we propose a triangle-based view interpolation algorithm which can correctly resolve the visibility problem without depth-buffering. The algorithm is especially useful when depth information is not available, such as in the case of real-world photographs. By subdividing the reference image into variable-sized triangles, view interpolation can be done efficiently using existing gr...

The present R graphics system was originally written as a placeholder, which could be replaced when a better alternative became available. This temporary solution has now become so entrenched that it is probably no longer possible to remove it. In this paper we will look at some of what is possible in the R graphics system, how it could be improved, and what might not be fixable. We will also l...

Pen and ink rendering techniques provide artistic, illustrative, and informative representations of objects. With recent advances in hardware graphics technology, several researchers have developed interactive non-photorealistic rendering techniques, including hatching, toon rendering, and silhouettes. However, the stippling method of drawing and shading using dots has not received as much focu...

The first assignment of the Fachpraktikum Graphics-Programming of the institute Visualisierung und Interaktive Systeme (short: FaPra) will teach you how to program a 3D graphics application. The X11 window system is used for the presentation of the graphical user interface. The application features common elements like a menu bar, a tool bar, a drawing area, and a status line. In the drawing ar...

The computation of good viewpoints is important in several fields: computer graphics, removal of degeneracies in computational geometry, robotics, graph drawing, etc. However, in areas such as computer graphics there is no consensus on what a good viewpoint means and, consequently, each author uses his or her own definition according to the requirements of the application. In this paper we pres...

The increasing complexity of models for prediction of the native spatial structure of RNA molecules requires visualization methods that help to analyze and understand the models and their predictions. This paper improves the visualization method for sequences of barrier trees previously published by the authors. The barrier trees of these sequences are rough topological simplifications of chang...

In this paper a process visualisation development system and its associated development methodology are presented. This methodology is optimised to systems that have complex structure and are built of large number of components belonging to relatively small number of types. In order to handle the complexity, the input requirements of the method is as close to the ”native language” of the applic...

A semi-fragile watermarking algorithm for authenticating 2D engineering graphics based on log-polar coordinates mapping is proposed. Firstly, the coordinates of vertices of entities are mapped to the log-polar coordinate system to obtain the invariance of translation, scaling and rotation. Then the watermark is embedded in the mantissa of the real-valued log-polar coordinates via bit substituti...

GXL provides an international standard to exchange graphs and their according schemas, but without offering means to visualize these structures. This paper presents a declarative approach to specify a graph layout by referring to the graphs schema. Using GReQL graph querying technology, the resulting display of graph elements can be influenced by various graph properties. The graph visualizer G...