== Surface Generator ==
Besides ICON: [[EMFile:surf_gen_tool_tn.Cubepng]] MENU: '''Object → Surface → Surface Generator''' TO DRAW A PARAMETRIC SURFACE: # Activate the '''Surface Generator Tool'''s standard planar objects, i.e# Left-click to establish the location of the new parametric surface. rectangle stripA default 2D sinusoidal surface appears in the project workspace.# The surface generator dialog opens up on the lower left corner of the screen. You have three options for '''Orientation''': XY, circle stripYZ or ZX planes. With the XY plane orientation, radial stripthe parametric surface is expressed as z = f(x, ellipse stripy). With the YZ plane orientation, triangle stripthe parametric surface is expressed as x = f(y, taper stripz). With the ZX plane orientation, regular polygonthe parametric surface is expressed as y = f(z, spiral stripx). # Enter start, polystrip stop and NURBS strip, you can use '''Surface Generator''' [[File:surf_gen_tool_tnstep values for the ranges of both coordinate variables in the selected orientation plane.png]] to create # Enter a large variety mathematical expression in terms of other the coordinate variables in the selected orientation plane for the definition of the parametric surface objects. Practically, any imaginable planar or non-planar # Make sure to click the OK button of the dialog to complete the surface construction. NOTES, SPECIAL CASES OR EXCEPTIONS: The property dialog of a NURBS strip object lists the individual nodes and their coordinates ordered by the node ID. You can be synthesized in [[EMselect and highlight each node and change its coordinates using the {{key|Edit}} button of the dialog.Cube]]You can also delete each node using the {{key|Delete}} key or insert a new node between the selected node and its next node using the {{key|Insert}} key. These includeThe new node is placed at the midpoint between the selected node and the node having the next ID number. PYTHON COMMAND:param_surface(label,x0,y0,z0,orientation,start_1,stop_1,step_1,start_2,stop_2,step_2,function)
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<td>[[Image:surf2a_tn_newCad surf11 new.png|thumb|left|640px480px|The curve surface generatordialog.]]
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A mathematical surface defined by z = sin(2*x)*exp(-y/2): (left) polymesh version, (right) smooth generic surface version.
# Click the '''Surface Generator'''[[File:surf_gen_tool_tn.png]] button of the '''Object Toolbar''' to open the Curve Generator Dialog.
# From the '''Model''' dropdown list, select the '''Custom Function''', which is the default option. Also specify the '''Orientation''' of the surface, which is the XY principal plane by default.
# Specify the range of the surface including '''Start''', '''Stop''' and '''Step''' values along the two specified dimensions.
# In the "Parameters" section, define the function representing the surface. This has the form z = f(x,y) in XY Plane, x = f(y,z) in YZ Plane or y = f(z,x) in ZX Plane.
# As in the previous case, you can choose between the two '''Polymesh''' or '''Generic Surface''' options. You can also preview the curve before finalizing its creation.
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<td>[[Image:cad_surf11Cad surf12 new.png|thumb|left|480px550px|The default 2D sinusoidal surface created by the surface generator dialog.]]
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