Engraving onto REVSURFs, RULESURFs and EDGESURFs
	The Engraving linear objects (Lines, LWPolylines, circular or elliptical arcs or 2D-Splines onto REVSURFs, RULESURFs or EDGESURFs can be done using the routines GRAV-ROT, GRAV-REG or GRAV-EDG. 1. Engraving onto REVSURFs The routine consists of 2 parts: GRAV-RO1 and GRAV-RO2. After loading and strarting the GRAV-ROT.vlx you get on opening screenwith informations how to use the routine. After starting the routine GRAV-RO1 the user is asked to pick the contour line to create the RULESURF by rotating this contourline around the Z-axis. The rectangular area - starting at 0,0 - for linework projection will be shown. Now it is time to creale or fill in the linework for projection into the rectangle. After starting the routine GRAV-RO2 the 2D linework will be projected onto the rotated 3D- surface area. You can control the accuracy of the projection. The projected elements are 3D-Polylines.