; TVDIST
;---------------------------------------------------------------
;! determines spherical distance between two pixels on TV screen
;# Verb Analysis Catalog TV
;-----------------------------------------------------------------------
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;;
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;-----------------------------------------------------------------------
TVDIST    LLLLLLLLLLLLUUUUUUUUUUUU CCCCCCCCCCCCCCCCCCCCCCCCCCCCC
TVDIST:  Determines spherical distance between 2 pixels on TV
         @      output adverbs
INNAME   @                         Image name(name).
INCLASS  @                         Image name(class).
INSEQ    @      0.0      9999.0    Image name(seq. #). 0=>high
INDISK   @      0.0         9.0    Disk drive #.       0=>any
PIXXY    @      0.0     16384.0    (X,Y,...) pixel in image
IN2NAME  @                         Second image name(name).
IN2CLASS @                         Second image name(class).
IN2SEQ   @      0.0      9999.0    Second image seq #.
IN2DISK  @      0.0         9.0    Second Disk drive #.
PIX2XY   @      0.0     16384.0    (X,Y,...) pixel in image
DIST     @                         Separation in degrees
----------------------------------------------------------------
TVDIST
Type: Procedure
Use: TVDIST asks the user to point out the end of the line between to
     points on the TV and then the beginning.  It then invokes IMDIST
     to determine the spherical angular distance between the points.
     Note that the TV can display more than one image ata time so that
     the two points may be from two disfferent images.
Adverbs (input):
     none
Output adverbs:
      First image pixel
  INNAME......Image name(name).        Standard defaults.
  INCLASS.....Image name(class).       Standard defaults.
  INSEQ.......Image name(seq. #).      0 => highest.
  INDISK......Disk drive # of image.   0 => any.
  PIXXY.......(X,Y,...) pixel location in image.  NOT zero
              on the X and Y axes anyway.
      Second image pixel
  IN2NAME.....Image name(name).        ' ' -> use 1st image
  IN2CLASS....Image name(class).       ' ' -> use 1st image
  IN2SEQ......Image name(seq. #).      0 -> use 1st image
  IN2DISK.....Disk drive # of image.   0 -> use 1st image
  PIX2XY......(X,Y,...) pixel location in image.  NOT zero
              on the X and Y axes anyway.
  DIST........Distance between pixels in degrees.
----------------------------------------------------------------
