Glyph-based 2D flow visualization

Abstract

Flow visualization is an important topic in scientific visualization. The focus of this work is to visualize 2-dimensional vector fields with existing Flow Radar Glyphs and field lines, mainly with pathlines. The idea of Flow Radar Glyphs is to visualize time-dependent data into a compact glyph. Flow Radar Glyphs show the Flow, and can be applied to other vector field properties. Tangents along pathlines are implemented as Flow Radar Glyphs (further referred to as 'tangential glyphs') in this work. More than one Pathlines in a data domain depicted in original size can intersect many times, therefore it is hard to keep them visually separated. In this work, the idea to solve this problem is to implement downscaled pathlines. Downscaled pathlines will be demonstrated and their gains will be examined. Another attempt to demonstrate the characteristics of pathlines are the tangential glyphs. Downscaled pathlines and tangential glyphs are the 2 focuses of this work. The visualization is implemented in C++, using OpenGL and GLSL compute shader. In the first place, the data sets are loaded into texture memory, in order to be accessed from the shader that can compute interpolations between seeding points using texture coordinates. The regular grid, on which the data is defined, makes the implementation in threads comfortable. For user interaction and instantaneous variable change and apply, AntTweakBar is used.