--- key: mechanic/phone-flashlight--family-shadows type: mechanic id: phone-flashlight--family-shadows lang: en title: Occlusion and shadows summary: >- Occluding light changes shadows and visible form. WildLight reconstructs scenes from lit images; a hand-shadow game needs its own recognition rules. updatedAt: '2026-10-22' status: active url: >- https://gamemechanics.pro/en/knowledge/mechanic/phone-flashlight--family-shadows/ jsonUrl: >- https://gamemechanics.pro/api/v1/knowledge/en/mechanic/phone-flashlight--family-shadows.json markdownUrl: >- https://gamemechanics.pro/content/knowledge/en/mechanic/phone-flashlight--family-shadows.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-shadows title: Phone flashlight interactions url: 'https://gamemechanics.pro/en/mechanics/phone-flashlight/#family-shadows' categoryIds: - section-1 supersededBy: [] attributes: preview: updatedAt: '2026-10-22' title: Occlusion and shadows description: >- Occluding light changes shadows and visible form. WildLight reconstructs scenes from lit images; a hand-shadow game needs its own recognition rules. 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: a lit object and the dark region beneath it' alt: 'WildLight: a lit object and the dark region beneath it' markers: - x: 32 'y': 30 label: The shadow depends on scene geometry and light position tips: - >- Prepare a high-contrast scene and do not treat every dark patch as a player gesture. 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 --- # Occlusion and shadows id: phone-flashlight--family-shadows type: mechanic key: mechanic/phone-flashlight--family-shadows lang: en status: active url: https://gamemechanics.pro/en/knowledge/mechanic/phone-flashlight--family-shadows/ Occluding light changes shadows and visible form. WildLight reconstructs scenes from lit images; a hand-shadow game needs its own recognition rules. ## At a glance ![WildLight: a lit object and the dark region beneath it](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 shadow depends on scene geometry and light position - Prepare a high-contrast scene and do not treat every dark patch as a player gesture. - [WildLight (research prototype)](https://junxuan-li.github.io/wildlight-website/) ## How it works The hand, object and screen become part of the optical interaction. ## Variants ### Variants and applications - Light curtain. Action: Block the light with your palm or a separate card. Application: Manual telegraph, hiding the signal from an opponent, theatrical effect. Requirements: Rear LED and control from the application; Prepared props or external sensor. Conditions: LED does not notice the damper; automatic entry requires separate monitoring. - Adjustment by hole. Action: Change the size of the gap between cards or fingers. Application: Physical light controller, experiment with the shape of the spot. Requirements: Rear LED and control from the application; Prepared props or external sensor. Conditions: Do not consider this to be the measured position of the "slider" without a camera or other sensor. - Closing the camera and LED together. Action: Change the “closed/open” state, blocking the camera area. Application: Tactile switch, conditional gesture of a hidden flashlight. Requirements: Rear LED and control from the application; Camera and proprietary image analysis. Conditions: Camera dimming analysis is only indirectly related to LED occlusion; The geometry of the phones is different. - Shadow silhouettes. Action: Create a recognizable outline with your hand or a figurine. Application: Shadow theatre, guessing an animal, retelling a story. Requirements: Rear LED and control from the application; Prepared props or external sensor. Conditions: Players can evaluate the result themselves; automatic recognition requires a surveillance camera. - Combining the shadow with the sample. Action: Move the object and source so that the shadow matches the outline. Application: Spatial puzzle, silhouette assembly, physics puzzle. Requirements: Rear LED and app control; Prepared props or external sensor; Camera and proprietary image analysis. Conditions: Camera or person evaluates shadow; one gyroscope is not enough... - Shadow scaling. Action: Change the distance between the source, object and surface. Application: Adjust the key to size, show the character's height, study the projection. Requirements: Rear LED and control from the application; Prepared props or external sensor. Conditions: Clarity depends on source size and distance; the beam does not become laser... - Rotate the shadow. Action: Rotate a volumetric object to the desired projection. Application: Recognize an object by silhouette, find a hidden letter, spatial puzzle. Requirements: Rear LED and control from the application; Prepared props or external sensor. Conditions: Prepare objects with truly distinguishable projections. - Assembling a general shade. Action: Combine the shadows of several objects into one sign. Application: Cooperative coat of arms, a puzzle made from scattered parts. Requirements: Rear LED and control from the application; Prepared props or external sensor. Conditions: The geometry must be verified with a physical mockup; the match does not occur automatically. - Shadow corridor. Action: Move the figurine so that its shadow remains within the acceptable area. Application: Board game of dexterity, sheet maze, cooperative challenge. Requirements: Rear LED and app control; Prepared props or external sensor; Camera and proprietary image analysis. Conditions: To calculate the result, you need a camera with a view of the field or a hand-held judge. - Recognition by shadow movement. Action: Identify an object or event by changes in silhouette. Application: Detective scene, guess the action, theatrical riddle. Requirements: Rear LED and control from the application; Prepared props or external sensor. Conditions: This is the player's interpretation; the application may not recognize the real silhouette. ## 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