28 Critical Reflections: random 1 t0 7
This can be explained by the existence of microfacets. We assume that surfaces that are not perfectly smooth are composed of many very tiny facets, each of which is a perfect specular reflector. These microfacets have normals that are distributed about the normal of the approximating smooth surface. The degree to which microfacet normals differ from the smooth surface normal is determined by the roughness of the surface. At points on the object where the smooth normal is close to the half-angle direction, many of the microfacets point in the half-angle direction and so the specular highlight is bright. As one moves away from the center of the highlight, the smooth normal and the half-angle direction get farther apart; the number of microfacets oriented in the half-angle direction falls, and so the intensity of the highlight falls off to zero.[6]
So, anyway, the people. Their clothes were shiny too, but lots of different colours. Skin-tight. They wore helmets with stubby aerials, and goggles. But the goggles had lines of information flickering across them.[2]
Even admitting that what happens in a camera obscura is something 'similar' to the phenomenon of the specular reflection (which is not questionable), what changes is the fact that an image remains traced somewhere, and any successive discussion about its iconic properties deals with the imprinted image and not with the process itself.[3]
"Shut up", I told the breakfast table. "I asked for coffee and waffles, not your dream from last night."
I finished my breakfast in a silence that was, I suspect, sulky on one side. "Reflective surfaces, huh? Sometimes they can get above themselves."[2]
Even admitting that what happens in a camera obscura is something 'similar' to the phenomenon of the specular reflection (which is not questionable), what changes is the fact that an image remains traced somewhere, and any successive discussion about its iconic properties deals with the imprinted image and not with the process itself.[3]
Oh yes, there were birds, but not like the birds you see today. Big as eagles and coloured like kingfishers. They roosted on the ledges of the towers, and under the ramps. Long curving ribbon ramps, with... Obviously these were too heavy to fly, so they had to go on the roads. Very fast. Automated, of course.[2]
The inside of River Form is not reminiscent of something formed by the flow of water. There are angles and worked surfaces that suggest deliberate, mindful workings; there are circles …[4]
28 Critical Reflections random 8 to 14
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Sources
[1] http://www.neworleanspast.com/art/id62.html
[2] Ken MacLeod, Reflective Surfaces, New Scientist, 2009.
[3] Umberto Eco, A Theory of Semiotics, Indiana University Press, 1979.
[4] Clive Fencott, Reflections on seeing River Form in Barbra Hepworth's garden in St. Ives.
[5] http://www.flickr.com/photos/nigelhomer/316548379/
[6] http://en.wikipedia.org/wiki/Specular_highlight