Basic Display Features of 3D Graphs

Managing the Display of Cube Lines

You can control whether the additional nine lines representing the intersection of all axis planes are displayed with the CUBE= option in the LAYOUT OVERLAY3D statement. The default is CUBE=TRUE.
layout overlay3d / cube=false ;
  surfaceplotparm x=height y=weight
                  z=density;
endlayout;
3D Layout with CUBE=FALSE

Displaying a Fill in the Graph Walls

By default, only the outlines of the walls bounding the XY, XZ, and YZ axis planes are shown. You can display filled walls by including the WALLDISPLAY=(FILL) or WALLDISPLAY=(FILL OUTLINE) settings in the LAYOUT OVERLAY3D statement. You can change the wall color (when filled) with the WALLCOLOR=option. When filled, the wall lighting is adjusted to give a 3D effect, based on the graph viewpoint.
layout overlay3d / cube=false
    walldisplay=(fill) ;
  surfaceplotparm x=height y=weight
                  z=density;
endlayout;
3D Layout with WALLDISPLAY=(FILL)

Defining a Viewpoint

Representing a 3D graph statically in two dimensions often obscures details that are better viewed from a different viewpoint. Three options on the LAYOUT OVERLAY3D statement can be independently set to obtain a different viewpoint.
Option
Value Range
Default
Description
ROTATE=
-360 to 360
54
Specifies the angle of rotation. Rotation is measured in a clockwise direction about a virtual axis, parallel to the Z axis (vertical) and passing through the center of the bounding cube. A counterclockwise rotation can be specified with a negative value.
TILT=
-360 to 360
20
Specifies the angle of tilt in degrees. Tilt is measured in a clockwise direction about a virtual axis parallel to the X axis (vertical) and passing through the center of the bounding cube. A counterclockwise tilt can be specified with a negative value.
ZOOM=
> 0
1
Specifies a zoom factor. Factors greater than 1 move closer to the bounding cube (zoom in), less than 1 move farther away (zoom out).
These options can be used in combination with each other to obtain a desired perspective. The following figures show some examples. To generate the figures, a LATTICE layout was used to "grid" a series of OVERLAY3D layouts of the same plot with different viewpoints. The arrows on the X and Y axes indicate increasing X and Y values.
Viewpoints with Different Rotation Angles
Viewpoints with Different Tilt Angles
Viewpoints with Different Zoom Factors

Defining Axes

Axes for the OVERLAY3D layout are similar to axes for the OVERLAY layout, although the following exceptions apply to OVERLAY3D layouts:
  • An additional ZAXISOPTS=( ) option is available for managing the Z axis.
  • All three axis types can be either LINEAR, LOG, or TIME. A DISCRETE axis is not supported on OVERLAY3D layouts.
  • No secondary (X2, Y2, Z2) axes are available on OVERLAY3D layouts.
  • Axis tick values are automatically thinned. No other fitting policy for OVERLAY3D layout is available.
  • For any axis, the location of the displayed axis features (line, ticks, tick values, and label) might shift, based on the specified viewpoint.
The following layout specification displays grid lines and a label for the Z axis:
layout overlay3d / cube=false
    zaxisopts=(griddisplay=on
    label="Kernel Density") ;
  surfaceplotparm x=height y=weight
                  z=density;
endlayout;
3D Layout with Z Axis Options