In certain conditions, the white walls at home take on the character of a light box. In traditional Japanese architecture the intensity of atmosphere has a lot to do with the way natural light is filtered through the shoji paper panels, suffusing the interior spaces with subdued light, calming the spirit and sharpening the senses.
In optics, a caustic is the envelope of light rays reflected or refracted by a curved surface or object, or the projection of that envelope of rays on another surface. The caustic is a curve or surface to which each of the light rays is tangent, defining a boundary of an envelope of rays as a curve of concentrated light.
A piece of milled plexiglass acting as a projecting lens; via the Computer Graphics and Geometry Lab at the École Polytechnique Fédérale de Lausanne
New milling techniques applied to glass and plexiglass panels could be used to “create windows that are also cryptic projectors, summoning ghostly images from sunlight.”
[Pauly and Bompas] hope that the technique will be used in architectural design, to create windows that mould sunlight and throw images or patterns onto walls or floors,” which, if timed, milled, and manipulated just right, could produce a slowly animated sequence of images being projected by an otherwise empty window during different times of day.
To control the shape of a caustic pattern generated by a specular or refractive surface, we need to solve the inverse problem: how can we change the surface geometry, such that incident light is redirected to produce a desired caustic image?
Reaching 95%-ile isn't very impressive because it's not that hard to do. I think this is one of my most ridiculable ideas. It doesn't help that, when stated nakedly, that sounds elitist. But I think it's just the opposite: most people can become (relatively) good at most things.
Note that when I say 95%-ile, I mean 95%-ile among people who participate, not all people (for many activities, just doing it at all makes you 99%-ile or above across all people). I'm also not referring to 95%-ile among people who practice regularly. The "one weird trick" is that, for a lot of activities, being something like 10%-ile among people who practice can make you something like 90%-ile or 99%-ile among people who participate.
Personally, in every activity I've participated in where it's possible to get a rough percentile ranking, people who are 95%-ile constantly make mistakes that seem like they should be easy to observe and correct. "Real world" activities typically can't be reduced to a percentile rating, but achieving what appears to be a similar level of proficiency seems similarly easy.