Conic map projections, in the normal and almost universal polar aspect, have as distinctive features:meridians are straight equidistant lines, converging at a point which may or not be a pole. Compared with the sphere, the angular distance between meridians is always reduced by a fixed factor, the cone constantparallels are arcs of circle, concentric in the point of convergence of meridians. As a consequence, parallels cross all meridians at right angles and the pattern of distortion is constant along each parallel. Given the same constant, different cone projections are distinguished only by parallel spacingFor illustration purposes, the resulting shape can be wrapped on a cone set atop the mapped sphere, although all important conic projections are not based on true geometric perspective — in other words, the conic surface is always the projection's result, but seldom directly participates in its construction.
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