{"schemaVersion":1,"record":{"key":"mechanic/phone-camera--family-motion-2d","type":"mechanic","id":"phone-camera--family-motion-2d","lang":"en","title":"Motion in the image plane","summary":"Frames become movement directions and paths. Active Arcade reads player motion through the camera; the phone needs a stable position and a clear body view.","updatedAt":"2026-10-22","status":"active","url":"https://gamemechanics.pro/en/knowledge/mechanic/phone-camera--family-motion-2d/","jsonUrl":"https://gamemechanics.pro/api/v1/knowledge/en/mechanic/phone-camera--family-motion-2d.json","markdownUrl":"https://gamemechanics.pro/content/knowledge/en/mechanic/phone-camera--family-motion-2d.md","aliases":[],"tags":["Phone camera interactions","Mechanics catalog"],"sourceIds":["source-c121374ae20b1406","source-c571f972753e630a","source-186323c99307fc90"],"sources":[{"id":"source-c121374ae20b1406","title":"Apple AVFoundation: Camera Capture and Control","url":"https://developer.apple.com/documentation/avfoundation/capture-setup","verifiedAt":null},{"id":"source-c571f972753e630a","title":"MediaPipe Object Detector","url":"https://developers.google.com/edge/mediapipe/solutions/vision/object_detector","verifiedAt":null},{"id":"source-186323c99307fc90","title":"Active Arcade","url":"https://apps.apple.com/us/app/active-arcade/id1553158383?uo=4","verifiedAt":null}],"sections":[{"id":"principle","title":"How it works","body":"The flow of frames turns into directions, speeds and trajectories. Without additional cues, camera movement and object movement are easy to confuse. Need a fixed phone, markers or motion compensation."},{"id":"variants","title":"Variants","body":"### Variants and applications\n\n<a id=\"family-motion-2d-variants\"></a>\n\n- Entrance to the area. Action: Bring a hand or object into the marked area to press a virtual button. Application: Non-contact interface, children's game, reaction. Technologies: Image analysis. <a id=\"variant-cam-041\"></a>\n- Crossing the line. Action: Move an object through the virtual boundary in the desired direction. Application: Goal, pass counter, conveyor sorting. Technologies: Image analysis. <a id=\"variant-cam-042\"></a>\n- Movement speed. Action: Move the target faster or slower, changing the force of the action. Application: Impact, character acceleration, visual musical instrument. Technologies: Image analysis. <a id=\"variant-cam-043\"></a>\n- Flow direction. Action: Move the scene or controller left, right, up or down. Application: Steering, swiping, touchless navigation. Technologies: Image analysis. <a id=\"variant-cam-044\"></a>\n- Trajectory as a symbol. Action: Draw a circle, zigzag or other shape with the target's movement. Application: Runes, gesture passwords, flight drawing. Technologies: Image analysis. <a id=\"variant-cam-045\"></a>\n- Fading. Action: Keep the image or selected object still. Application: “Freeze”, sight stabilization, virtual neutralization. Technologies: Image analysis. <a id=\"variant-cam-046\"></a>\n- Repeat route. Action: Draw the tracked point along the pattern with an acceptable deviation. Application: Coordination training, labyrinth, copying a picture. Technologies: Image analysis. <a id=\"variant-cam-047\"></a>\n- Area of ​​change. Action: Move so as to fill the required portion of the frame with changes. Application: Acceleration of the elements, collective activity, abstract dance. Technologies: Image analysis. <a id=\"variant-cam-048\"></a>"},{"id":"context","title":"Context and limits","body":"Games, learning, creativity and interactive applications. Author's systematization of game rules based on proven technical capabilities. Examples are application ideas and not statements of released products."}],"relations":[],"placements":[{"catalogId":"phone-camera","id":"family-motion-2d","title":"Phone camera interactions","url":"https://gamemechanics.pro/en/mechanics/phone-camera/#family-motion-2d","categoryIds":["section-1"]}],"supersededBy":[],"attributes":{"preview":{"updatedAt":"2026-10-22","title":"Motion in the image plane","description":"Frames become movement directions and paths. Active Arcade reads player motion through the camera; the phone needs a stable position and a clear body view.","image":{"src":"images/mechanics/input-active-arcade-1.webp","width":720,"height":405,"crop":{"x":225,"y":60,"width":495,"height":285},"game":"Active Arcade","sourceUrl":"https://apps.apple.com/us/app/active-arcade/id1553158383?uo=4","originalUrl":"https://is1-ssl.mzstatic.com/image/thumb/PurpleSource115/v4/a6/f6/47/a6f64733-077d-715b-80b4-dfef3fecf396/8e690756-92fb-4664-952a-0adc89822d2d_body-motion-gameplay-.jpg/720x1560bb.jpg","credit":"Nex","rights":"Imagery © Nex. Developer-distributed screenshot or frame; all rights reserved. Excluded from MIT and CC BY 4.0.","caption":"Active Arcade: a person’s movement participates in gameplay","alt":"Active Arcade: a person’s movement participates in gameplay","markers":[{"x":65,"y":43,"label":"The camera sees the player while the game adds scores and effects"}]},"tips":["Separate player motion from camera shake and show the usable tracking area."],"examples":[{"title":"Active Arcade","url":"https://apps.apple.com/us/app/active-arcade/id1553158383?uo=4"}]}},"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/phone-camera"}}