Animations for scroll and zoom

摘要

Smooth animation effects during zooming are provided by retaining content displayed at a previous zoom level. If the zoom operation is a zoom out operation, new content is stretched to a current zoom level, aligned with the retained content, and placed underneath it. If the zoom operation is a zoom in operation, new content is scaled down to the current zoom level, aligned with the retained content, and displayed on top of the retained content. The new content is then zoomed with the retained content. The retained content is then deleted. When zooming out, the retained content fades out. When zooming in, the new content fades in. Smooth scrolling animation is also provided by pre-rendering a portion of content and teleporting to a final viewport position and thereby skipping over blank content.

主权项

1. A method comprising:
receiving first indication to initiate a zoom operation to an intermediate selected zoom level; receiving intermediate content corresponding to the intermediate selected zoom level; rendering the intermediate content at the intermediate selected zoom level; retaining old content rendered at an initial zoom level to provide retained content; receiving, within a predetermined amount of time, a second indication to initiate a zoom operation to a final selected zoom level; based on receiving the second indication within the predetermined amount of time, receiving final content corresponding to the final selected zoom level, discarding the intermediate content, and continuing to retain the old content; displaying the final content at a current zoom level at its current fidelity and aligned with the retained content; rendering the final content at the final selected zoom level to provide rendered final content; animating a zooming of the final content with the retained content from the initial zoom level to the final selected zoom level; and displaying the rendered final content.