gleLathe(3GLE)								GLE							    gleLathe(3GLE)

NAME

       gleLathe - Sweep using a Z-axis shear to create an arbitrary contour along a helical path.

SYNTAX

       void gleLathe (int ncp,
		       gleDouble contour[][2],
		       gleDouble cont_normal[][2],
		       gleDouble up[3],
		       gleDouble startRadius,	  /* spiral starts in x-y plane */
		       gleDouble drdTheta,	  /* change in radius per revolution */
		       gleDouble startZ,	  /* starting z value */
		       gleDouble dzdTheta,	  /* change in Z per revolution */
		       gleDouble startXform[2][3], /* starting contour affine xform */
		       gleDouble dXformdTheta[2][3], /* tangent change xform per revoln */
		       gleDouble startTheta,	  /* start angle in x-y plane */
		       gleDouble sweepTheta);	  /* degrees to spiral around */

ARGUMENTS

       ncp	 number of contour points

       contour	 2D contour

       cont_normal
		 2D contour normals

       up	 up vector for contour

       startRadius
		 spiral starts in x-y plane

       drdTheta  change in radius per revolution

       startZ	 starting z value

       dzdTheta  change in Z per revolution

       startXform
		 starting contour affine transformation

       dXformdTheta
		 tangent change xform per revolution

       startTheta
		 start angle in x-y plane

       sweepTheta
		 degrees to spiral around

DESCRIPTION

       Sweep  an  arbitrary  contour along a helical path. The sweep will be performed as a shear along the z-axis, so that the orientation of the
       contour is displaced, rather than translated, as the contour is swept.

       The axis of the helix lies along the modeling coordinate z-axis.

       An affine transform can be applied as the contour is swept. For most ordinary usage, the affines should be given as NULL.

SEE ALSO

       gleSpiral

AUTHOR

       Linas Vepstas (linas@linas.org)

GLE
									3.0							    gleLathe(3GLE)