Zoom–pan order changes path length and total time

What it is

In multi-scale navigation, zooming before panning is not equivalent to panning before zooming. Zoom changes screen-coordinate distance and visible extent, while pan changes target position in the viewport; different zoom–pan paths produce different gesture counts, screen travel, reorientation, and total time.

Why it happens

Zooming first can push a distant target outside the view and require long panning. Panning first retains global context at lower scale but may misalign focus after zoom. The useful order depends on initial offset, scale gap, zoom anchor, and landmark visibility. Path cost is not a simple sum of two fixed operation times.

Studying it

Have people use or be assigned different orders for matched start and target conditions, logging scale, viewport centre, gesture time, reversals, and lost targets. Compare end-to-end time and path length by distance and density. Do not measure only one gesture; reorientation often occurs between them.

Where it stops holding

Automatic target anchoring, direct jumps, and target-centering reduce order differences. Inertia, discrete levels, and touch gestures change paths too. In exploratory work, a longer route may yield information value and should not be judged only by time.

Related

• Same group: B1.15.1 In an infinitely zoomable space, time grows with relative index difference, not absolute scale · B1.15.3 Losing peripheral context during zoom forces reorientation · B1.15.4 Automatic zoom saves time only when target prediction is correct
• Nearby: B1.10 Multi-scale pointing · B1.05 Steering law
• Search terms: zoom pan path · path planning · multi-scale navigation