Shiver Development: Event Density + Time Charting

For the past few days, I decided to develop a type of visualization which attempts to better communicate the areas that have a high density of earthquakes over time. I decided to do this by having the program create a texture on the fly which is fed into the primary globe fragment shader, where areas of high seismic event activity would get higher amounts of red. Since the texture being created is simply a collection red blobs on a black background, it is simple process to add the red areas on top of the globe through the shader. Additionally, the seismic events themselves are visualized through simple lines aligned to the normals of the sphere - with the length of the line determined by its Richter scale value.



Fig 1.1: Globe with event density visualization

After wrapping up event density mapping, I wanted to start trying to visualize events as they occurred over time. The visualization itself doesn't communicate time as much as it displays the erratic nature of seismic activity happening around the world over an extended period (currently, over seven days). To create lines that seemingly wrap themselves around the curvature of the globe - I decided to write a small bezier curve generator which had end points at the 3D coordinates of selected events. The distance of those events is calculated using the Euclidean distance formula of:

Where the distance value is used to apply weight (w) to midpoints in rational bezier curves, such that:

Fig 1.2: Bezier curves mapped across globe based on time of occurrence