28 Critical Reflections: random 22 to 28
But the first thing to make clear is that a specular reflection cannot be taken as a sign if one follows the definition given in this book. Not only can it not be properly called an image (since it is a virtual image, and therefore not a material expression) but even granted the existence of the image it must be admitted that it does not stand for something else:on the contrary it stands in front of something else, it exists not instead of but because of the presence of that something: when that something disappears the pseudo-image in the mirror disappears too.[3]
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 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]
'Abstract' is a word which is now most frequently used to express only the type of the outer form of a work of art; this makes it difficult to use it in relation to the spiritual vitality or inner life which is the real sculpture. Abstract sculptural qualities are found in good sculpture of all time, but it is significant that contemporary sculpture and painting have become abstract in thought and concept. As the sculptural idea is in itself unfettered and unlimited and can choose its own forms, the vital concept selects the form and substance of its expression quite unconsciously.[7]
And I know this sounds odd, but most of the flying people were carrying briefcases. Maybe it was their lunch, or maybe... I don't know, it could have been they needed paper, for some purpose I didn't understand.[2]
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]
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]
28 Critical Reflections: random 1 to 7
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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.
[5] http://www.flickr.com/photos/nigelhomer/316548379/
[6] http://en.wikipedia.org/wiki/Specular_highlight