Graphical projection Perspective projection is a linear projection where three dimensional objects are projected on a "picture plane". This has the effect that distant objects appear smaller than nearer objects. It also means that lines which are parallel in nature (that is, meet at the point at infinity) appear to intersect in the projected image, for example if railways are pictured with perspective projection, they appear to converge towards a single point, called vanishing point. Photographic lenses and the human eye work in the same way, therefore perspective projection looks most realistic. Perspective projection is usually categorized into "one-point", "two-point" and "three-point
Microsoft Point-to-Point Compression Microsoft Point-to-Point Compression Microsoft Point-to-Point Compression (MPPC; described in RFC 2118) is a streaming data compression algorithm based on an implementation of Lempel–Ziv using a sliding window buffer. According to Hifn's IP statement, MPPC was patent-encumbered (last US patent granted on 1996-07-02). Where V.44 or V.42bis operate at layer 1 on the OSI model, MPPC operates on layer 2, giving it a significant advantage in terms of computing resources available to it. The dialup modem's in-built compression (V.44 or V.42bis) can only occur after the data has been serially transmitted to the modem, typically at a maximum rate of 115,200