English: A movie showing spot scattering. Collision of two travelling spots as shown in snapshots in Figure 11. Panels A-C in the animation correspond to rows A-C of that figure, and displayed content and parameters are discussed in its caption. Note that time t=0 in the figure corresponds to t=36.95 in the animation. To initially create the traveling spots, two spot solutions in u with radius 2.8 are used, with two co-located discs in a of the same radius. The discs have a linear gradient along the abscissa from zero to 0.5g, while having uniform values along the ordinate. The mean position of the u≥h regions of the pulses is kept track of during time evolution and used to estimate the current velocities. The 34×34 domain was discretized by a 1,024×1,024 grid. (AVI 17.0 MB)