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.RotationThe call glRotate*(a, x, y, z) generatesR as follows.Let v = (x, y, z)T, and u = v/||v|| = (x',y', z').Also letThenThe R matrix is always defined.If x=y=z=0, then Ris the identity matrix.You can obtain the inverse of R, R-1,by substituting -a for a, or by transposition.The glRotate*() command generates a matrix for rotation aboutan arbitrary axis.Often, you're rotating about one of the coordinate axes;the corresponding matrices are as follows.As before, the inverses are obtained by transposition.Perspective ProjectionThe call glFrustum(l, r, b, t, n,f ) generates R, where:R is defined as long as l not equal to r, tnot equal to b, and n not equal to f.Orthographic ProjectionThe call glOrtho*(l, r, b, t, u, f ) generates R, where:R is defined as long as l not equal to r, tnot equal to b, and n not equal to f.[Previous chapter] [Nextchapter]See the About page for copyright, authoringand distribution information
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