{"schemaVersion":1,"record":{"key":"mechanic/trackpad--family-05","type":"mechanic","id":"trackpad--family-05","lang":"en","title":"Scrolling and timelines","summary":"Two-finger scrolling moves through a document without changing its scale. Preview uses this to navigate PDF pages and thumbnails.","updatedAt":"2026-10-22","status":"active","url":"https://gamemechanics.pro/en/knowledge/mechanic/trackpad--family-05/","jsonUrl":"https://gamemechanics.pro/api/v1/knowledge/en/mechanic/trackpad--family-05.json","markdownUrl":"https://gamemechanics.pro/content/knowledge/en/mechanic/trackpad--family-05.md","aliases":[],"tags":["Trackpad interactions","Mechanics catalog"],"sourceIds":["source-0d7ed8efcd920b62","source-7641af4e83c63a96","source-80fb36760a664f26","source-27c6b989daeb79c9","source-8303b0f3aad42806","source-3b576ce1cd2451ef","source-2aa43929eb995c4c"],"sources":[{"id":"source-0d7ed8efcd920b62","title":"macOS Gestures","url":"https://support.apple.com/en-us/102482","verifiedAt":null},{"id":"source-7641af4e83c63a96","title":"Windows Gestures","url":"https://support.microsoft.com/en-us/windows/hardware/input-devices/touch-gestures-for-windows","verifiedAt":null},{"id":"source-80fb36760a664f26","title":"AppKit: contacts and system gestures","url":"https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/EventOverview/HandlingTouchEvents/HandlingTouchEvents.html","verifiedAt":null},{"id":"source-27c6b989daeb79c9","title":"libinput: swipe, pinch, hold","url":"https://wayland.freedesktop.org/libinput/doc/latest/gestures.html","verifiedAt":null},{"id":"source-8303b0f3aad42806","title":"W3C: Pointer Events","url":"https://www.w3.org/TR/pointerevents/","verifiedAt":null},{"id":"source-3b576ce1cd2451ef","title":"Steam Input: Surface Modes","url":"https://partner.steamgames.com/doc/features/steam_controller/input_source_modes?language=english","verifiedAt":null},{"id":"source-2aa43929eb995c4c","title":"Preview (macOS)","url":"https://support.apple.com/guide/preview/view-pdfs-and-images-prvw11470/11.0/mac/26","verifiedAt":null}],"sections":[{"id":"principle","title":"How it works","body":"Scrolling is converted into movement across space, a scale of values ​​or time with an explicitly specified sensitivity."},{"id":"variants","title":"Variants","body":"### Variants and applications\n\n<a id=\"family-05-variants\"></a>\n\n- Vertical scrolling. Gesture: Move two fingers up or down. In the interface: Documents, lists, change a parameter. In the game: Selecting an item, sight height, camera zoom. Access level: Ready gesture; You need a gesture transmitted by the OS or framework: scroll, zoom, rotate, swipe or hold. The set varies. Conditions: The OS can issue wheel deltas. The direction depends on the natural scrolling setting. <a id=\"variant-41\"></a>\n- Horizontal scrolling. Gesture: Move two fingers left or right. In the interface: Wide canvas, paths, table. In the game: Horizontal camera, change lane or position. Access level: Ready gesture; You need a gesture transmitted by the OS or framework: scroll, zoom, rotate, swipe or hold. The set varies. Conditions: The browser or OS can use this move to navigate back and forth. <a id=\"variant-42\"></a>\n- Free panning. Gesture: Use both scrolling components at the same time. In the interface: Map, large diagram, 2D canvas. In game: Review of the strategy or tactical map field. Access level: Ready gesture; You need a gesture transmitted by the OS or framework: scroll, zoom, rotate, swipe or hold. The set varies. Conditions: Not every stack transmits equally accurate continuous deltas. <a id=\"variant-43\"></a>\n- Inertial scrolling. Gesture: After a push, continue moving with deceleration. In the interface: Long tapes, catalogs, panoramas. In the game: Scrolling the wheel of objects, inertial view. Access level: Ready gesture; You need a gesture transmitted by the OS or framework: scroll, zoom, rotate, swipe or hold. The set varies. Conditions: Inertia can be created by the OS or application; You can't use it twice. <a id=\"variant-44\"></a>\n- Touch to stop momentum. Gesture: Place your fingers on the panel to stop movement. In the interface: Quickly stop kinetic scrolling. In game: Slow down the spinning wheel or view. Access level: Ready gesture; You need a gesture transmitted by the OS or framework: scroll, zoom, rotate, swipe or hold. The set varies. Conditions: An explicit hold/touch signal is required. libinput describes hold; The regular wheel API does not guarantee this. <a id=\"variant-45\"></a>\n- Edge scrolling. Gesture: Move one finger along the edge of the surface. In the interface: Continuous navigation, one-finger scrolling. In the game: Inventory ribbon or vertical camera movement. Access level: Individual contacts; You need access to coordinates, phases and contact IDs. The presence of multitouch on the device does not guarantee this. Conditions: Driver mode or access to the panel area is required; This is not a universal app gesture. <a id=\"variant-46\"></a>\n- Circular scrolling. Gesture: Rotate your finger in a circle, accumulating an angle. In the interface: Long list, virtual wheel, change the number. In the game: Setting up a safe, reel, flywheel. Access level: Individual contacts; You need access to coordinates, phases and contact IDs. The presence of multitouch on the device does not guarantee this. Conditions: Possible through a special surface display; alternative in the application: circular drag cursor. <a id=\"variant-47\"></a>\n- Scroll by steps. Gesture: Convert accumulated deltas into discrete switches. In the interface: Select a line, frame, division or tool. In the game: Enumerate weapons, change the bet step. Access level: Ready gesture; You need a gesture transmitted by the OS or framework: scroll, zoom, rotate, swipe or hold. The set varies. Conditions: Do not consider each wheel event as a separate stage: their frequency depends on the device. <a id=\"variant-48\"></a>\n- Scrubbing. Gesture: Scroll to continuously change position on the time axis. In the interface: Video, sound, animation, history of changes. In the game: View replay, control time rewind. Access level: Ready gesture; You need a gesture transmitted by the OS or framework: scroll, zoom, rotate, swipe or hold. The set varies. Conditions: The position value and playback speed are different displays of the same input. <a id=\"variant-49\"></a>\n- Rough and fine scrubbing. Gesture: Change the scale of time adjustment using a modifier. In the interface: Search for a scene with a transition to frame-by-frame precision. In the game: Exact stop of a repeat or time puzzle. Access level: Ready gesture; You need a gesture transmitted by the OS or framework: scroll, zoom, rotate, swipe or hold. Set varies. Conditions: A second physical axis outside of normal scrolling may require T; the modifier key is simpler. <a id=\"variant-50\"></a>"},{"id":"context","title":"Context and limits","body":"Author's working classification for designing games and interactions. Options can overlap and combine; the list is not a generally accepted standard or proven exhaustive list. Application examples are conditional unless a specific verifiable observation is indicated nearby. Sources support individual techniques and technical limitations."}],"relations":[],"placements":[{"catalogId":"trackpad","id":"family-05","title":"Trackpad interactions","url":"https://gamemechanics.pro/en/mechanics/trackpad/#family-05","categoryIds":["section-1"]}],"supersededBy":[],"attributes":{"preview":{"updatedAt":"2026-10-22","title":"Scrolling and timelines","description":"Two-finger scrolling moves through a document without changing its scale. Preview uses this to navigate PDF pages and thumbnails.","image":{"src":"images/mechanics/control-macos-preview.webp","width":788,"height":750,"game":"Preview (macOS)","sourceUrl":"https://support.apple.com/guide/preview/view-pdfs-and-images-prvw11470/11.0/mac/26","originalUrl":"https://help.apple.com/assets/67DB77BFAE89A3DDC700A869/67DB77C0E2208881620C3D38/en_US/918f957676bf215f21f57328147e8435.png","credit":"Apple","rights":"© Apple. Official support screenshot; all rights reserved. Excluded from MIT and CC BY 4.0.","caption":"Preview: a document page and a scrollable thumbnail sidebar","alt":"Preview: a document page and a scrollable thumbnail sidebar","markers":[{"x":13,"y":67,"label":"Thumbnails relate scrolling to the position in the document"}]},"tips":["Distinguish scrolling from pinching and respect OS direction and inertia."],"examples":[{"title":"Preview (macOS)","url":"https://support.apple.com/guide/preview/view-pdfs-and-images-prvw11470/11.0/mac/26"}]}},"endsAt":null,"provenance":"Original editorial design catalog consolidated from project discussions on 2026-10-20. Complete discussion item lists and contextual limitations are preserved; linked primary sources support specific techniques, not the entire classification. English translation was prepared with machine assistance and editorial review.","license":"CC-BY-4.0","codeLicense":"MIT","attribution":"gamemechanics.pro contributors","catalogKey":"catalog/trackpad"}}