 WALK                                                        Menu:VIEW / SOLID
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 Modifies the eye position by a relative displacement.
 (A nested command in the geometric module only.)

  1.If in geometric module:
        1.  (Y/N) option: on sphere? (y), around axis? (n) <y>
    if reply is `y', if in perspective mode:
        2.  (CHAR) (persp.) walking direction (b,f,u,d,l,r)
    if reply is `y', if in parallel mode:
        2.  (CHAR) (paral.) walking direction (u-up, d-down, l-left, r-right)
    for options `b' and `f', if in perspective mode:
        3.  (NUM) walking distance
    for options `u' and `d':
        3.  (NUM) angle (in degrees)
    for options `l' and `r':
        3.  (NUM) angle (+/- 0-360 deg.)
    if reply to prompt 1 is `n':
        2.  (CHAR) axis (x,y or z)
        3.  (NUM) rotation angle (+/- 0-360 deg.)


  2.If in solid module:
    if in perspective mode:
        1.  (CHAR) (persp.) walking direction (b,f,u,d,l,r)
    if reply is `y', if in parallel mode:
        1.  (CHAR) (paral.) walking direction (u-up, d-down, l-left, r-right)
    for options `b' and `f', if in perspective mode:
        2.  (NUM) walking distance
    for options `u' and `d':
        2.  (NUM) angle (in degrees)
    for options `l' and `r':
        2.  (NUM) angle (+/- 0-360 deg.)

  3.If in the solid module and current display mode is `o'(off).
        1.* (CHAR) (persp.) walking direction (b,f,u,d,l,r)
    if reply is `y', if in parallel mode:
        1.* (CHAR) (paral.) walking direction (u-up, d-down, l-left, r-right)
    for options `b' and `f', if in perspective mode:
        2.* (NUM) walking distance
    for options `u' and `d':
        2.* (NUM) angle (in degrees)
    for options `l' and `r':
        2.* (NUM) angle (+/- 0-360 deg.)

 Description:

 This command modifies the eye position by a relative displacement.
 Its behavior is determined by the current module.

 In the geometric module only you are asked whether you wish to move
 the eye position around a sphere or about an axis. If you select the
 former or if you are in the solid module, you state the walking direction
 (u=up, d=down, b=back, f=forward, l=left, r=right) and specify
 the displacement or angle.

 Back and forward displacements are given in units of length (according
 to the current unit), relative to the original eye position. (These
 options are only applicable in perspective mode).

 Left, right, up and down displacements are given in degrees. These
 displacements are performed on an imaginary sphere whose center is
 the target and whose surface represents the eye location. While left
 and right movement may be specified by any positive or negative value
 between 0 and 360, the up and down movement is limited to 89
 (the poles) from the XY plane.


 If you select to rotate the eye about an axis while in the geometric
 module, state the axis and give a rotation angle.

 If you are currently in the geometric module or in any of the display
 modes set by the \dsmod command in the solid module, the screen
 will be redrawn in the appropriate display mode. If you are in
 the solid module and the display mode is currently "off",
 the new view will not be displayed until a new display mode is specified,
 enabling you to execute a series of manipulations before the screen
 is redrawn.

