Shadow Smart Lab

Every shadow in this app is computed, not painted. Most science apps show you a picture of a shadow. Shadow Smart Lab gives you the light source and gets out of the way. Drag the lamp across the sky and the shadow stretches. Turn the object and the outline changes. Widen the source and the edge goes soft. The maths runs live, sixty times a second, on the actual geometry of the solid in front of you. A REAL LIGHTING ENGINE, NOT A SPRITE Eight procedural solids: cube, sphere, pyramid, cylinder, cone, torus, prism and arch Every vertex ray-projected from the lamp onto the ground plane, so rings keep their holes and arches keep their gap Penumbra width driven by real source size and distance, exactly like a physical soft box Add a second lamp and get a second shadow, with the overlap resolved correctly Four materials, including translucent glass that thins its own shadow SIX TOPICS, TAUGHT BY EXPERIMENT ● Shadow length: why noon shortens you and evening stretches you, and where 1 / tan comes from ● Shadow direction: reading a bearing off the ground and turning any stick into a compass Eclipses: a full simulator with angular radii, so you can drive the Moon out to apogee and watch a total eclipse turn annular Silhouettes: why a backlit subject loses everything except its outline Reflection: a law-of-reflection bench where roughness morphs one clean ray into a diffuse spray Perspective: vanishing points, and why a shadow grows as the object approaches the lamp LEARN, THEN PROVE IT 30 lessons, each with its own live animated diagram rather than a static illustration 30 quiz questions with explanations, five per topic 21 challenges across three difficulties: hit a target shadow length, bearing, orientation or softness Difficulty changes the tolerance and hides the live numbers, so Advanced makes you estimate A new seeded daily experiment every morning FIVE PLACES TO WORK Laboratory, Desert, Forest, Space and City at Night Each has its own sky, ground, ambient fill, source softness and reflectivity, so the same object behaves differently in each BUILT TO FEEL GOOD Full dark and light themes, plus system Glassmorphic panels, animated backgrounds and a cinematic-motion switch for anyone who wants it calmer Subtle haptics on every control, switchable Progress, streaks, levels, 16 achievements and charts of where your mastery actually sits No account. No subscription. No network. Everything runs on device.