SCALE3

The SCALE3 procedure sets up transformation and scaling parameters for basic 3D viewing. This procedure is similar to SURFR and SCALE3D, except that the data ranges must be specified and the scaling does not vary with rotation. Results are stored in the system variables !P.T, !X.S, !Y.S, and !Z.S.

This routine is written in the IDL language. Its source code can be found in the file


scale3.pro

in the

lib

subdirectory of the IDL distribution.

Keywords

XRANGE

A two-element vector containing the minimum and maximum X values. If omitted, the X-axis scaling remains unchanged.

YRANGE

A two-element vector containing the minimum and maximum Y values. If omitted, the Y-axis scaling remains unchanged.

ZRANGE

A two-element vector containing the minimum and maximum Z values. If omitted, the Z-axis scaling remains unchanged.

AX

Angle of rotation about the X axis. The default is 30 degrees.

AZ

Angle of rotation about the Z axis. The default is 30 degrees.

Example

Set up a 3D transformation where the data range is 0 to 20 for each of the 3 axes and the viewing area is rotated 20 degrees about the X axis and 55 degrees about the Z axis:

SCALE3, XRANGE=[0, 20], YRANGE=[0, 20], ZRANGE=[0, 20], AX=20, AZ=55