Motion of animated streamlets appears to surpass their graphical alterations in human visual detection of vector field maxima

Animations have become a frequently utilized illustration technique on maps but changes in their graphical loading remain understudied in empirical geovisualization and cartographic research. Animated streamlets have gained attention as an illustrative animation technique and have become popular on widely viewed maps. We conducted an experiment to investigate how altering four major animation parameters of animated streamlets affects people’s reading performance of field maxima on vector fields. The study involved 73 participants who performed reaction-time tasks on pointing maxima on vector field stimuli. Reaction times and correctness of answers changed surprisingly little between visually different animations, with only a few occasional statistical significances. The results suggest that motion of animated streamlets is such a strong visual cue that altering graphical parameters makes only little difference when searching for the maxima. This leads to the conclusion that, for this kind of a task, animated streamlets on maps can be designed relatively freely in graphical terms and their style fitted to other contents of the map. In the broader visual and geovisual analytics context, the results can lead to more generally hypothesizing that graphical loading of animations with continuous motion flux could be altered without severely affecting their communicative power.动画已成为地图领域常用的图示表达手段，但其图形负载（graphical loading）的相关变化在实证地理可视化与地图学研究中仍未得到充分探讨。动态流线（animated streamlets）作为一种动画可视化手法已受到学界关注，并在广受浏览的各类地图中得到广泛应用。本研究开展了一项控制实验，探究动态流线的四项核心动画参数调整，如何影响受试者对矢量场（vector fields）中场极大值（field maxima）的读取表现。本次实验共招募73名受试者，要求其完成指向矢量场刺激物中极大值的反应时任务。结果显示，视觉呈现效果存在差异的动画之间，受试者的反应时与答题正确率仅存在极细微的差异，仅存在少量偶发的统计学显著性差异。研究结果表明，动态流线的运动本身属于极强的视觉线索，因此在搜索极大值时，调整图形参数对任务表现的影响微乎其微。由此可得出结论：针对此类任务，地图上的动态流线可在图形层面进行较为自由的设计，其风格可与地图其他内容相适配。在更广泛的视觉与地理可视化分析语境下，本研究结果可进一步引申出一般性研究假设：带有连续运动流的动画，其图形负载可在不对其信息传播效力造成严重影响的前提下进行调整。