vcylmap − maps 3D image file to cylindrical model polygon file

vcylmap [if=<image file in short format>] [sf=<cylindrical model polygon file>] [of=<mapped polygon file>] [x=<polynomial coefficients for ’x(t)’>] [y=<polynomial coefficients for ’y(t)’>] [z=<polynomial coefficients for ’z(t)’>] [si=<sampling interval in voxels>] [sd=<sampling distance>] [tf=<temporary (debugging) vector file>]

vcylmap

Maps image intensity information to model cylinder polygon file. Intensity information is sampled given the curve defined by the parametric polynomial in 3D space. Parameters x, y, z are used to specify the coefficients of polynomials. If, the equation of the curve is defined as: x(t) = 50*t^3 + 50*t - 25; y(t) = 50*t^2 - 25; z(t) = 60*t^2 + 60*t - 60, parameters should be set up as: x=50,0,50,-25 y=0,50,0,-25 z=0,60,60,-60. The part of the curve used for sampling is bounded in the interval of parameter t = (0...1).

For each triangle of the cylindrical model polygon file, parameter ’t’ is equal to ’z’ coordinate of the polygon’s center point. Direction of the polygon is computed as the angle between direction of ’x’ axis and the vector connecting axis and the center of the polygon.

For each value of ’t’, corresponding cross-sectional plane is sampled. This plane is perpendicular to the tangent vector of the curve and intersects it at the tangent point x(t), y(t), z(t). Then rays lying on this plane are casted from the tangent point in the precomputed directions of polygons. The values of image intensity are sampled in the interval ’si’ and recorded to the floating point vector format. Last sampling point is located at distance ’sd’ from the tangent point. After sampling procedure is done, the vector of sampled values is anchored to the corresponding polygon of the model.

if=

image file in short format

sf=

cylindrical model polygon file

of=

mapped polygon file

x=

polynomial coefficients for ’x(t)’

y=

polynomial coefficients for ’y(t)’

z=

polynomial coefficients for ’z(t)’

si=

sampling interval in voxels

sd=

sampling distance

tf=

temporary (debugging) vector file

-p

inhibit packing of result

Only cubic polynomials are supported

vvec2(1), vadjtopol(1), vadjtover(1), vpoltoadj(1), vpoltover(1), vvertoadj(1), vvertopol(1), vcylmodel(1), vdmap(1), vpolcolor(1), vpoldiv(1), vpolmap(1), vpolimap(1), vpoltosph(1), vsphtopln(1), vvertoang(1)

Sergei Fotin, November 2006