--- key: mechanic/phone-flashlight--family-movement type: mechanic id: phone-flashlight--family-movement lang: en title: Direction and movement of the phone summary: >- Moving the phone changes object lighting. The WildLight research prototype uses images with a moving LED to recover shape and reflectance. updatedAt: '2026-10-22' status: active url: >- https://gamemechanics.pro/en/knowledge/mechanic/phone-flashlight--family-movement/ jsonUrl: >- https://gamemechanics.pro/api/v1/knowledge/en/mechanic/phone-flashlight--family-movement.json markdownUrl: >- https://gamemechanics.pro/content/knowledge/en/mechanic/phone-flashlight--family-movement.md aliases: [] tags: - Phone flashlight interactions - Mechanics catalog sourceIds: - source-486438ca6bfacdc6 sources: - id: source-486438ca6bfacdc6 title: WildLight (research prototype) url: 'https://junxuan-li.github.io/wildlight-website/' verifiedAt: null relations: [] placements: - catalogId: phone-flashlight id: family-movement title: Phone flashlight interactions url: 'https://gamemechanics.pro/en/mechanics/phone-flashlight/#family-movement' categoryIds: - section-1 supersededBy: [] attributes: preview: updatedAt: '2026-10-22' title: Direction and movement of the phone description: >- Moving the phone changes object lighting. The WildLight research prototype uses images with a moving LED to recover shape and reflectance. image: src: images/mechanics/flash-wildlight.webp width: 1440 height: 387 crop: x: 285 'y': 0 width: 283 height: 132 game: WildLight (research prototype) sourceUrl: 'https://junxuan-li.github.io/wildlight-website/' originalUrl: 'https://junxuan-li.github.io/wildlight-website/static/images/teaser.jpg' credit: 'Ziang Cheng, Junxuan Li, Hongdong Li' rights: >- © Ziang Cheng, Junxuan Li, Hongdong Li. Author-distributed research figure; respective rights retained. Excluded from portal MIT and CC BY 4.0. caption: 'WildLight: an object photographed using the phone flashlight' alt: 'WildLight: an object photographed using the phone flashlight' markers: - x: 29 'y': 24 label: The flashlight image shows changed lighting on the model car tips: - >- Distinguish device orientation, light position and the camera-visible light patch. examples: - title: WildLight (research prototype) url: 'https://junxuan-li.github.io/wildlight-website/' 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-flashlight --- # Direction and movement of the phone id: phone-flashlight--family-movement type: mechanic key: mechanic/phone-flashlight--family-movement lang: en status: active url: https://gamemechanics.pro/en/knowledge/mechanic/phone-flashlight--family-movement/ Moving the phone changes object lighting. The WildLight research prototype uses images with a moving LED to recover shape and reflectance. ## At a glance ![WildLight: an object photographed using the phone flashlight](https://gamemechanics.pro/images/mechanics/flash-wildlight.webp) [WildLight (research prototype)](https://junxuan-li.github.io/wildlight-website/) · © Ziang Cheng, Junxuan Li, Hongdong Li. Author-distributed research figure; respective rights retained. Excluded from portal MIT and CC BY 4.0. 1. The flashlight image shows changed lighting on the model car - Distinguish device orientation, light position and the camera-visible light patch. - [WildLight (research prototype)](https://junxuan-li.github.io/wildlight-website/) ## How it works Posture, speed and trajectory turn the phone into a handheld tool. ## Variants ### Variants and applications - Targeting. Action: Align the direction of the phone with the target. Application: AR pointer, exhibit selection, virtual spotlight. Requirements: Rear LED and app control; Motion sensors and calibration; Camera and spatial tracking; Software game rule. Conditions: Sensors provide orientation; binding to a specific real goal requires tracking or a tag. - Direction hold. Action: Do not move the phone out of the permissible angle for a specified time. Application: Stabilize the signal, study a virtual object, play for accuracy. Requirements: Rear LED and control from the application; Motion sensors and calibration; Software game rule. Conditions: It is possible to evaluate stability relative to the initial pose without recognizing the room. - Tracking a moving target. Action: Rotate the phone after the object. Application: Accompanying a virtual creature, guarding a moving load. Requirements: Rear LED and control from the application; Motion sensors and calibration; Camera and proprietary image analysis; Software game rule. Conditions: The real target requires video tracking; the game itself knows the virtual target... - Search by sector. Action: Consistently illuminate the directions around the initial pose. Application: In-game room scanner, overview of hidden virtual threats. Requirements: Rear LED and control from the application; Motion sensors and calibration; Software game rule. Conditions: Gyroscope needs calibration; it does not confirm that actual surfaces have been inspected. - Outline outline. Action: Swipe the phone along a given line. Application: Drawing a symbol, setting up an antenna, restoring a picture. Requirements: Rear LED and control from the application; Motion sensors and calibration; Software game rule. Conditions: Without a camera, a corner path is recognized, not a line on the wall. - Passage speed control. Action: Pass the light slowly or quickly without leaving the range. Application: Virtual scanning, image “developing”, musical glissando. Requirements: Rear LED and control from the application; Motion sensors and calibration; Software game rule. Conditions: Angular velocity can be estimated by sensors; the speed of the light spot requires the geometry of the scene. - Order of directions. Action: Shine up, down, left and right in the desired order. Application: Spatial password, dance team, ritual. Requirements: Rear LED and app control; Motion sensors and calibration; Software game rule. Conditions: Fix the frame of reference and tolerances before the start of the round. - Rotation around an axis. Action: Rotate the phone like a dial, maintaining the direction. Application: Select a conditional filter, scanner frequency or instrument mode. Requirements: Rear LED and control from the application; Motion sensors and calibration; Software game rule. Conditions: Program mode changes; the actual LED spectrum does not change depending on rotation. - Approaching the surface. Action: Change the distance to the object and the size of the illuminated area. Application: Selecting the scale of the shadow, examining the texture, AR task at a distance. Requirements: Rear LED and control from the application; Prepared props or external sensor; Camera and proprietary image analysis. Conditions: Automatic distance estimation requires a known marker, tracking or depth sensor. - Moving the source to a new point. Action: Move the phone relative to the object, and not just turn it. Application: Study the relief from the other side, get the desired shadow, explore the scene. Requirements: Rear LED and control from the application; Prepared props or external sensor; Camera and spatial tracking. Conditions: The actual displacement can be seen by a person; Coordinates for the game require positional tracking. ## Context and limits 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. ## Connected materials ## Sources and 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. - [WildLight (research prototype)](https://junxuan-li.github.io/wildlight-website/) (id: source-486438ca6bfacdc6) CC-BY-4.0 · gamemechanics.pro contributors