


                                  - 1 -



       COMMAND

       ddddiiiissssppppllllaaaayyyy,,,, eeeeddddiiiitttt ---- iiiimmmmaaaaggggeeee ddddiiiissssppppllllaaaayyyy aaaannnndddd eeeeddddiiiittttiiiinnnngggg ffffuuuunnnnccccttttiiiioooonnnnssss

       USAGE

       ddddiiiissssppppllllaaaayyyy

       eeeeddddiiiitttt

       DESCRIPTION FOR THE _I_R_I_S WORKSTATION

       The _I_r_i_s color graphics workstations from Silicon Graphics
       can create a variety of displays from the image data.  The
       display command has been reduced to just the eeeeddddiiiitttt or ddddiiiissssppppllllaaaayyyy
       command without arguments.  Both commands are identical, two
       names for the same thing.  All of the options are selected
       with the mouse and _p_o_p-_u_p _m_e_n_u_s.

       The selections made available on the menus vary greatly from
       release to release and depend on the software version
       obtained.  This description will assume the current full
       featured release.

       The _I_r_i_s _4_d version of the program is somewhat different
       from the _I_r_i_s _3_1_3_0 version.  The most significant difference
       is the fact that windows must be _a_t_t_a_c_h_e_d prior to using
       them.

       When the ddddiiiissssppppllllaaaayyyy or eeeeddddiiiitttt command is given, three windows
       will be created.

       _H_e_l_p            This small HHHHeeeellllpppp window will indicate what
                       the _E_c_h_o program is expecting you to do.
                       Its menu has only one selection, which is
                       EEEExxxxiiiitttt EEEEddddiiiitttt, to return you to the prompt.

       _W_i_r_e_f_r_a_m_e       This window displays the image as a
                       wireframe.  The wireframe defaults to being
                       drawn at a medium resolution which gives
                       speedy interaction.  The default of DDDDeeeepppptttthhhhccccuuuueeee
                       causes lines to be drawn darker as they get
                       further away.

       _R_e_n_d_e_r          This window presents rendered, or shaded,
                       views of the image.  It is usually used to
                       show the shaded version of the view
                       currently positioned in the _W_i_r_e_f_r_a_m_e
                       window.  The menus of this window are
                       extensive.












                                  - 2 -



       You should already know how to operate the _I_r_i_s windows.
       Generally, windows are selected whenever the mouse pointer
       is in the window.  The RRRRiiiigggghhhhtttt mouse button is used to select
       from menus.  The LLLLeeeefffftttt mouse button usually stops whatever
       action the menu selection started.  The MMMMiiiiddddddddlllleeee mouse button
       is used for picking and editing.

       Many selections expect you to move the mouse to control the
       viewpoint or other transformation.  If the mouse pointer
       moves out of the window, the window is de-selected and no
       longer receives the mouse movements.  The official _I_r_i_s
       method is to hold the SSSShhhhiiiifffftttt or CCCCoooonnnnttttrrrroooollll key down whenever the
       mouse pointer is outside the window.  This maintains the
       selection of the window.

       Many of the menu selections toggle a mode either on or off.
       The current mode may not be indicated on the menu.  The
       resulting display usually gives enough clues to determine
       the current mode.  Most mode changes will be reflected in
       the menu.

       The menu selections for the WWWWiiiirrrreeeeffffrrrraaaammmmeeee menu are:

       RRRRoooottttaaaatttteeee          Moving the mouse adjusts the azimuth and
                       inclination of your viewpoint (eye).

       ZZZZoooooooommmm            Moving the mouse up and down zooms your
                       viewpoint in and out.

       PPPPaaaannnn             Moving the mouse up, down, left and right
                       moves your viewpoint respectively.

       PPPPeeeerrrrssssppppeeeecccc         Moving the mouse up and down changes the
                       perspective.  This is the distance from the
                       viewpoint to the object.

       TTTTwwwwiiiisssstttt           Rarely useful, this twists your viewpoint,
                       like tilting your head.

       OOOOsssscccciiiillllllllaaaatttteeee       Used in demonstration situations, the
                       rotation will be constantly varied.

       RRRReeeessssoooolllluuuuttttiiiioooonnnn      A sub-menu which allows the wireframe
                       resolution to be adjusted.  Slower
                       workstations will need a lower resolution to
                       provide suitable response time.  The value
                       selected here does not affect the _R_e_n_d_e_r
                       window.  A pointer indicates the current
                       selection.













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       OOOOppppttttiiiioooonnnnssss         When the mouse is moved in the direction of
                       the arrow on this item a _s_u_b-_m_e_n_u will be
                       displayed.  Its contents are described
                       below.

       EEEExxxxiiiitttt            Terminates the eeeeddddiiiitttt or ddddiiiissssppppllllaaaayyyy command,
                       erases the windows and returns to the _E_c_h_o
                       prompt.

       The following selections are found on the _W_i_r_e_f_r_a_m_e _O_p_t_i_o_n_s
       sub-menu.  These are selected by moving the mouse pointer
       left or right on one of the main menu selections which
       indicates it has a sub-menu by the presence of an arrow next
       to the selections name.

       SSSShhhhoooowwww aaaannnndddd HHHHiiiiddddeeee     The wireframe may be drawn using lines of
                         constant longitude, lines of constant
                         latitude, or both.  Interaction will be
                         slowed as the number of lines drawn is
                         increased.  Both types of lines cannot be
                         _h_i_d_d_e_n because _E_c_h_o will always draw at
                         least one type.  An arrow indicates the
                         current type.

       PPPPeeeerrrrssssppppeeeeccccttttiiiivvvveeee       The wireframe is normally projected with
                         perspective.  To remove all perspective,
                         which is not possible with the mouse, you
                         may select the OOOOrrrrtttthhhhooooggggrrrraaaapppphhhhiiiicccc projection.

       DDDDrrrraaaawwwwiiiinnnngggg VVVVooooiiiidddd DDDDaaaattttaaaa Data values which are _V_o_i_d can be treated
                         two different ways.  Usually they are not
                         drawn and will cause a discontinuity in
                         the latitude or longitude.  The void
                         values may also be defaulted to a value of
                         0 if necessary.

       DDDDeeeepppptttthhhhccccuuuueeee          Because hidden line removal is not
                         performed, the far lines can cause
                         confusion in the displayed image.
                         Depthcue mode makes distant lines dimmer
                         than closer lines, making the display
                         clearer.

       BBBBuuuuffffffffeeeerrrriiiinnnngggg         To display the images while it is being
                         drawn you may select SSSSiiiinnnngggglllleeee BBBBuuuuffffffffeeeerrrr mode.
                         DDDDoooouuuubbbblllleeee BBBBuuuuffffffffeeeerrrriiiinnnngggg can give flicker-free
                         movement during transformations.  Not all
                         workstations support double buffering.

       The RRRReeeennnnddddeeeerrrr WWWWiiiinnnnddddoooowwww also has menus.  Many of these menu item
       are the same as those already described for the Wireframe











                                  - 4 -



       Window.

       RRRReeeeddddrrrraaaawwww            Causes the window to be redrawn.  Since
                         this may take a few seconds, the window is
                         usually not redrawn until you request it.
                         The image will be redrawn using the same
                         viewpoint selected for the WWWWiiiirrrreeeeffffrrrraaaammmmeeee
                         window unless the UUUUsssseeee LLLLooooccccaaaallll TTTTrrrraaaannnnssssffffoooorrrrmmmm
                         selection has been selected.

       TTTTrrrraaaannnnssssffffoooorrrrmmmm         The items on this sub-menu allow this
                         window's viewpoint to be moved independent
                         of the WWWWiiiirrrreeeeffffrrrraaaammmmeeee window's viewpoint.  This
                         is often too slow for interaction unless
                         the resolution has been reduced
                         significantly or the image cccclllliiiipppped to a
                         smaller size.  To access the tranformation
                         items, first select the UUUUsssseeee LLLLooooccccaaaallll
                         TTTTrrrraaaannnnssssffffoooorrrrmmmm item.  Then re-select this menu
                         to get the transformation selections.

                         To return to the default mode of copying
                         the Wireframe Window's transforms select
                         the WWWWiiiirrrreeeeffffrrrraaaammmmeeee TTTTrrrraaaannnnssssffffoooorrrrmmmm item.

       MMMMoooovvvveeee LLLLiiiigggghhhhtttt        When using one of the lighting model modes
                         (described below) you may move the light
                         source.  The light is always positioned
                         relative to your head, like a miner's
                         lamp.  When it is moved it is still
                         relative to the viewer's head except it
                         may be some angle away.  The light source
                         cannot be moved up and down, it only moves
                         about horizontally.

                         While complicated to explain, the fact
                         that the light is relative to your head
                         make the lighting consistent as you move
                         around the object under harsh lighting
                         conditions.

                         It can be a little difficult to control
                         with the mouse.  The display resolution is
                         automatically lowered during mouse
                         movements to speed the interaction.
                         Resolution is restored after the light is
                         moved.

       MMMMeeeetttteeeerrrr PPPPooooiiiinnnnttttssss      The mouse controls a crosshair pointer
                         that is always drawn on the surface of the
                         object.  Side to side mouse movements











                                  - 5 -



                         select the longitude, up and down
                         movements select the latitude.  When the
                         middle mouse button is clicked, the text
                         window will display the coordinates of the
                         point.  You might want to zoom in a little
                         for high precision work.

                         The displayed text will show the vertex
                         indexes, the value in the range map at
                         this vertex, the eqivalent cartesian
                         coordinates, the color value at this
                         vertex, and the straight line distance
                         from the previously metered vertex.

       CCCClllliiiipppp DDDDaaaattttaaaa         Used with the MMMMeeeetttteeeerrrr PPPPooooiiiinnnnttttssss tool above.
                         The selected clipping boundary (see
                         llllggggrrrraaaannnnggggeeee) is moved to the latitude or
                         longitude of the most recently metered
                         point.  Most commonly used by metering at
                         the low latitude/longitude point of the
                         desired clipping _r_e_c_t_a_n_g_l_e and then
                         selecting LLLLaaaattttiiiittttuuuuddddeeee MMMMiiiinnnn and LLLLoooonnnnggggiiiittttuuuuddddeeee MMMMiiiinnnn.
                         This clips off both low sides.  This
                         procedure is then repeated for the high
                         latitude/longitude corner.

       UUUUnnnnCCCClllliiiipppp DDDDaaaattttaaaa       Sets the clipping window to the full image
                         for the edge selected.

       SSSSuuuurrrrffffaaaacccceeee MMMMaaaatttteeeerrrriiiiaaaallllssss You may select one of several surface
                         materials for the lighting model or select
                         NNNNoooo LLLLiiiigggghhhhttttiiiinnnngggg to disable the lighting
                         computations.  Without lighting the
                         surface will need to have surface colors
                         supplied by one of the TTTTeeeexxxxttttuuuurrrreeee MMMMaaaapppp
                         functions described below.

       RRRReeeennnnddddeeeerrrr OOOOppppttttiiiioooonnnnssss    The data is normally rendered using
                         TTTTrrrriiiiaaaannnngggglllleeeessss.  Void data points are draw at 0
                         radius (or Z) in this mode.  The
                         QQQQuuuuaaaaddddrrrriiiillllaaaatttteeeerrrraaaallllssss selection causes the
                         rendering to be performed with four vertex
                         polygons instead of triangles.  This also
                         causes void verticies to be efficiently
                         skipped.

                         The RRRReeeelllliiiieeeeffff RRRReeeessssiiiizzzzeeee selection causes the
                         window to be resized to the proper size
                         for making reliefs.  On the IIIIrrrriiiissss 3333000000000000
                         SSSSeeeerrrriiiieeeessss it is necessary to invoke the
                         window margin RRRReeeessssiiiizzzzeeee command to trigger











                                  - 6 -



                         the resizing.  The RRRReeeelllliiiieeeeffff SSSSccccaaaannnn selection
                         causes the image presently being displayed
                         to become a 3-D relief.  The current
                         viewpoint is used in the calculation.  The
                         relief data replaces the current image
                         data.  To view the relief it is necessary
                         to exit to the prompt and re-issue the
                         eeeeddddiiiitttt command.

       TTTTeeeexxxxttttuuuurrrreeee MMMMaaaapppp       These commands control the surface
                         material coloring.  The surface may be
                         colored by the lighting models selected
                         above, or by _p_e_r _v_e_r_t_e_x color values.
                         These color values can be from several
                         sources.  The radius (or Z) value of each
                         vertex can be used as an index into a
                         color ramp.  This creates a _t_o_p_o_g_r_a_p_h_i_c
                         effect which shows the surface contours in
                         an interesting way.  The SSSSmmmmooooooootttthhhhnnnneeeessssssss
                         function examines each vertex and compares
                         its radius (or Z) value to its immediate
                         neighbors.  The difference is used to
                         select a color from a color ramp.  This
                         function will highlight surface features
                         and roughness.

       EEEExxxxiiiitttt              Terminates the eeeeddddiiiitttt or ddddiiiissssppppllllaaaayyyy command,
                         erases the windows and returns to the _E_c_h_o
                         prompt.  The image is unchanged except for
                         any clipping performed by the CCCClllliiiipppp
                         commands.




























