7ef8676a_Photo_Editing_with_Aperture__Multi_Touch_trackpad_gestures
[Feature] Viewer and Full Screen view (Viewer mode) [Multi-Touch trackpad gestures] 
Use the pinch gesture to zoom in to and out of the image. Use the rotate gesture to rotate the image beneath the pointer. Use the swipe gesture to select a different image when “Scroll to navigate photos in the Viewer” is selected in the General pane of the Preferences window. For more information about the General pane of the Preferences window, see General Preferences. For more information about the swipe gesture, see Mac Help.
Photo Editing with Aperture
Multi-Touch trackpad gestures