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]
The singularity of specular reflections is demanded by the fact that if one tries to apply to them the schema of communicational process many puzzling questions arise: source and addressee coincide (at least in cases where a human looks at him or herself in the mirror); receiver and transmitter coincide; expression and content coincide since the content of the reflected image is just the image of a body, not the body itself; as a matter of fact the referent of a mirror image is pure visual matter.[3]
Reflection can be used for observing and/or modifying program execution at runtime. A reflection-oriented program component can monitor the execution of an enclosure of code and can modify itself according to a desired goal related to that enclosure.[6]
What alien/other peoples from other-worldly, past or future cultures would have made such a grouping of monolithic structures out of aluminium, brushed or stainless steel? The alien, the natural, the primitive, the advanced coincide in Hepworth's works and garden.[4]
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]
The image in a mirror is not a sign for it and cannot be used in order to lie (if not by producing a false object to be reflected, but in this case what stands for the supposed object is the false body, not its reflection).[3]
The term specular means that light is perfectly reflected in a mirror-like way from the light source to the viewer. Specular reflection is visible only where the surface normal is oriented precisely halfway between the direction of incoming light and the direction of the viewer; this is called the half-angle direction because it bisects (divides into halves) the angle between the incoming light and the viewer. Thus, a specularly reflecting surface would show a specular highlight as the perfectly sharp reflected image of a light source. However, many shiny objects show blurred specular highlights.[6]
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