{"schemaVersion":1,"record":{"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}],"sections":[{"id":"principle","title":"How it works","body":"The hand, object and screen become part of the optical interaction."},{"id":"variants","title":"Variants","body":"### Variants and applications\n\n<a id=\"family-shadows-variants\"></a>\n\n- 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. <a id=\"variant-31\"></a>\n- 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. <a id=\"variant-32\"></a>\n- 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. <a id=\"variant-33\"></a>\n- 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. <a id=\"variant-34\"></a>\n- 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... <a id=\"variant-35\"></a>\n- 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... <a id=\"variant-36\"></a>\n- 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. <a id=\"variant-37\"></a>\n- 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. <a id=\"variant-38\"></a>\n- 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. <a id=\"variant-39\"></a>\n- 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. <a id=\"variant-40\"></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":"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"}}