Browse Prior Art Database

Portraying a Three Dimensional Cursor

IP.com Disclosure Number: IPCOM000108995D
Original Publication Date: 1992-Jul-01
Included in the Prior Art Database: 2005-Mar-23
Document File: 3 page(s) / 117K

Publishing Venue

IBM

Related People

Rabenhorst, DA: AUTHOR

Abstract

Disclosed is a two-dimensional representation of a three-dimensional cursor to indicate a readily discernible three-dimensional position, section, or slice of a solid on a computer screen. It is comprised of several simultaneous and unique two-dimensional cursors.

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This is the abbreviated version, containing approximately 52% of the total text.

Portraying a Three Dimensional Cursor

       Disclosed is a two-dimensional representation of a
three-dimensional cursor to indicate a readily discernible
three-dimensional position, section, or slice of a solid on a
computer screen.  It is comprised of several simultaneous and unique
two-dimensional cursors.

      The technique is to use a conventional engineering-type line
drawing of a solid in axonometric rectangular block form.  The line
drawing may be in either isometric, dimetric, trimetric, perspective,
or hybrid projection.  For clarity of perception and speed of
representation, the hidden lines are not shown.  Such a line drawing
shows three visible faces of a rectangular solid, which may be
described as:
      1.  the front x-y face at z=0
      2.  the right y-z face at x=X
      3.  the top  x-z face at y=Y

      An example in cavalier projection is shown in the top right
portion of the figure.  The origin is in the lower left corner of the
visible front face.  X increases from 0 to X from left to right, y
increases from 0 to Y from bottom to top, and z increases from 0 to
Z from front to back.  Alternative choices for axes, orientation, and
projection may of course be chosen.

      For output display purposes, a three-dimensional focal position
within the rectangular block is indicated by simultaneously
indicating its position on each of the three visible faces of the
solid.  A good choice is to use a cross-hair pointer covering each of
the three faces from edge to edge.

      For input purposes, a two-dimensional pointing device (such as
conventional mouse) effectively selects any pair of two of the three
dimensions by selecting a visible face on the line drawing.  When the
pointer is placed within any one of the faces in the line drawing, it
effectively specifies two of the three dimensions.

      Input and output are coupled so that when the pointer selects a
point within one of the faces (as by clicking on it), the
corresponding position indicators on each of the three faces change
simultaneously as appropriate.  For example, if a new point is
selected for x,y in the front face, both cross-hair lines on the
front face and their extensions wrapping around the other two faces
get re-displayed at their new point of intersection on the front
face.

      If, instead, only x and y had changed by an update on the front
face, only the x and y cross-hairs and their extensions would change,
but on all three faces.  In this case, the only cross-hair lines
which would not change are the two indicating z, which wrap from
horizontal on the top face to vertical on the right face.

      The changes on the computer screen are made rapidly and
dynamically so that when the pointe...