OVERVIEW:

StageStills is an external Geomview module that makes it easy to
obtain snapshots of a Geomview window.  These snapshots can be in any
image format, and you have control over how many colors to use, what
size to make the image, and whether to produce a large image and then
reduce it to the desired size (for anti-aliasing).

The functionality of StageStills is also available within StageManager,
but since snapshots are such a common thing to want, it seemed useful
to have a separate module for obtaining images easily.


STARTING STAGESTILLS:

Once geomview is running, select StageStills from the modules panel.
This will load StageStills, and after a moment, you should see the
StageStills panel.


THE STAGESTILLS PANEL:

The StageStills panel contains a type-in area for the camera name,
buttons for viewing images and taking snapshots, several pull-down
menus, and a quit button.

The type-in area lets you specify which Geomview camera you are
interested in taking a snapshot of.  Usually this is "Camera" or "c0",
but if you are using ND-view you may have several cameras to choose
from.  Type the name of the camera here.

The SIZE menu shows you the size of the image you will be making.  By
default, it is set to the size of the window when StageHand was
started, but you can change it either by selecting one of the standard
sizes (MpegSize or VideoSize), by setting it to the current size of
the camera window (Get Current Size), or by specifying the size
explicitly (Set Size...).  The final image produces will be the size
showing for this menu.

The SCALE menu lets you specify the ratio between the image produced
by Geomview and the final image produced by StageStills.  A ratio of
1:1 means they are the same, but 2:1 means the image is first created
at twice its final size, then reduces by 50% to produce the final
image.  This can produce better-quality images, since anti-aliasing
can be done to reduce the "jaggies" at the edges of objects.  The cost
is that it takes longer to produce the image.

The COLORS menu lets you specify how many colors to use in the final
image.  Some formats (e.g., TIFF, PNM, JPEG) allow you to use millions of
colors, but others (e.g., GIF) can only represent 256 colors.  You may
also wish to reduce the number of colors to make the final file size
smaller or for other effects.  The COLORS menu lets you do this.

The COLORS menu also includes a check-box for DITHERING.  If this is
checked, then the colors in the final image will be blended together
(dithered) to prevent sharp transitions from one color to another.  As
a result, however, there will be few large areas of a single color,
including the background, so if you intend to have a transparent
background color for a GIF image, you may not want to use dithering.

The SHADER menu lets you specify the mechanism for generating the
image.  SOFTWARE means that Geomview's internal software shader will be
used.  HARDWARE means a snapshot of the actual Geomview window is used
(this is only available on the SGI version of Geomview).  RENDERMAN
means that Geomview will produce .rib files that are then passed to
Renderman for processing.  This can take quite some time, but can also
produce very high-quality images.  This option is only available if
the "render" command is in your command path.  Finally, if the version
of Geomview you are using was compiled with the mesa library, the MESA
shader will be available as well.


TAKING A SNAPSHOT:

Once you have set the menus to your desired values, you should press
the SNAPSHOT button to make your picture.  This will bring up a
filename requester where you can specify the name of the file where
the snapshot will be stored.  The file type will determine the image
type, so if you want a GIF file, make sure your file name ends in
".gif", etc.  When you press the "Save" button, your snapshot will be
saved.

To see what your snapshot looks like, press the VIEW button.  You will
be asked to select a file to view, and then the image viewer will be
launched to show you the image.  This way you can easily check the
effects of different color/size/scale settings on the resulting image.
You can specify the command to use to view files by setting the
StageStills.viewer(Image) resource in your .Xdefaults file.


KNOW BUGS:

None.


BUG REPORTS AND COMMENTS:

Please send bug reports and comments to <mailto:dpvc@union.edu>.

