Griffin has had a significant rework for Cedar 6.0 and as a result has become a much better Cedar citizen. There are no longer any text editing capabilities in Griffin—if you need a string, select it in a convenient Tioga viewer somewhere. This applies to both file names and captions. You should be able to run Griffin from ///Commands/.

When you open a Griffin icon you will see two lines of Viewer menus at the top of the Griffin viewer. The top line consists of BiScroller menu functions, described below. The bottom line consists of Griffin menu buttons. These buttons are divided into two groups: "file" operations and a replacement for the "master" griffin menu.

Run Griffin from the CommandTool by typing:

Griffin.load will be executed, which will run:

Users may have any number of Griffin viewers simultaneously. To get an empty Griffin viewer, type Griffin (CR) to the Command Tool. To get a series of filled Griffin viewers type, for example,

to get four Griffin viewers on Griffin files fee.Griffin, fie.Griffin, foe.Griffin, and fum.Griffin from the "current" working directory. The current working directory is the one in which Griffin was originally run. If files cannot be found, empty viewers will appear with the message "Unknown file." File names may be full path names.

Griffin viewers are contained in a special kind of container called a BiScroller. See /Cedar/CedarChest@/Documentation/BiScrollersDoc.tioga for detailed information on BiScrollers. The features provided for Griffin by BiScrollers include vertical and horizontal scrolling and some transformations which affect what the user sees in the viewer. Note that these transformations are only temporary and apply only to the viewer and are not to be confused with actual Griffin transformations on Griffin objects invoked via the Transform menu.

All filing operations are done with new file operation menu buttons in the Griffin menu:

If you turn on the color display in 8 bit/pixel mode (use the ColorDisplay component of the Cedar release), you can run the Griffin viewer on the color display. NOTE: Unless you have a 1000 line monitor, you may be disappointed at the amount of screen real estate available.

The basic graphical unit in Griffin is the object. Single objects may be grouped in a cluster, which behaves as a single object for most operations. The basic unit to be printed or saved is the illustration, which may be composed of any number of objects.

There are three types of object in Griffin: shapes, captions, and control objects. Shapes consist of straight and curved lines, either singly or linked end-to-end into more complex figures, and may be either closed (end points linked) or open (end points not linked). Closed shapes may be filled with a solid color. Captions are composed of text only.

Control objects that may appear on the Griffin screen include menus, control points, a control grid, and a frame. Control points are used in defining the geometry of shapes, and are placed and deleted with the mouse. The grid is provided as an aid in placing objects and control points precisely. The frame is provided as an aid to cropping the set of Griffin objects to be used to create Interpress hardcopy files.

Every object has a geometry and a style. The geometry of shapes is defined by placing control points and then fitting lines or curves through them. For captions, the geometry consists of an anchor position and a text string. Style attributes include such things as color, line thickness, font, etc. The style of an object can be changed without affecting the geometry, and vice versa.

Objects have a definite order of overlap. A newly created object is always placed at the top; operations are available for explicitly changing and controlling the overlap order of the objects in an illustration. Filled shapes are opaque, obscuring those below them in the overlap order. Shapes that are not filled are transparent, except on the border.

All Griffin commands are entered by menu selection. Command arguments are taken from the current Tioga selection. Menu items are selected by clicking down over the desired item on the menu with any of the three mouse buttons. Outside of the menus, the three mouse buttons have different functions, described below under Mouse Operations'.

Menus appear on top of the picture being drawn; they can be moved around to provide access to all parts of the picture. The master menu, always present in the normal viewer menu, controls the display of other menus used for various specialized purposes. Each item on the master menu is a toggle that can be turned on and off by repeated clicking with the mouse. Turning one of these toggles on causes the associated menu to appear on the screen; when the toggle is turned off, the menu vanishes. If the user clicks a master menu item with left or middle click, the menus will toggle without moving. A right click forces a master menu to appear near the bottom of the current viewer, even if the viewer has been scrolled away from the former menu positions. Some of the second-level menus in turn include toggles that control even more specialized submenus.

Some menus, known as one-of-many menus, have the property that only one item on the menu may be selected at a time. Selecting any item on such a menu automatically deselects the previously selected item.

The following table summarizes the various menus available in Griffin and the toggles that control them.

Griffin uses each of the three mouse buttons for different operations, depending on whether you hold down the SHIFT and/or CONTROL key while pressing the button. The following table summarizes the mouse operations on object; CP means control point, and items marked ** invoke "grid defeat", explained below:

Shapes (graphical objects) are created and modified with the commands on the edit and shape menus, in conjunction with control points placed on the screen with the mouse. These menus are both controlled by the Edit' toggle on the master menu. Other attributes of the object to be created are specified on the various style menus (see Styles', below).

The operations described in this section are used for object-level manipulations within an illustration. All of these operations appear on the object, view, and overlap menus, which are controlled, respectively, by the Objects', View', and Overlap' toggles on the master menu.

Griffin offers a variety of transformations that may be applied to an object. All transformation operations appear on the transform menu, controlled by the Transform' toggle on the master menu. Only shape objects transform fully. For captions, only the anchor point is transformed

To transform one or more objects, select the objects to be transformed, place the transformation control points (details below under the various transformations), and click the appropriate item on the transform menu. The selected object(s) are erased, transformed, and redisplayed. If Use Copy' is selected on the transform menu, the original object is left undisturbed and a copy is created, placed on top in the overlap order, transformed as specified, and displayed. If the requested transformation would flatten the object in such a way that its original shape could not be recovered (for example, scaling it by zero), a warning message is displayed and the transformation is not performed.

Every object in a Griffin illustration has a style that defines various attributes of the object's appearance when displayed or printed. Styles are specified with the style menu, controlled by the Style' toggle on the master menu. The Color Style', Shape Style', and Text Style' toggles on the style menu in turn control the display of specialized style submenus for setting the style attributes of an object.

The style submenus remember'' their settings, even when they are not currently displayed on the screen. The state of all these menus together defines the current style, which is applied to any newly created object. All objects carry all style attributesfor example, every shape object has a font style. It is only possible to operate on the entire style for an object, not just one attribute. For instance, there is no way to change the color of several captions in one operation without also setting them all to the same font.

To read the style of an object, click Indicate' on the style menu. The current style is set to the style of the selected object, and all visible style submenus are updated accordingly. If more than one object is selected, the style of the topmost selected object becomes the current style.

To change the style of an object, select the object, set the desired attributes on the style submenus, then click Apply' on the style menu. All selected objects are given the current style, as defined by the current settings of the style submenus.

Griffin uses the Imager for text and assumes you want to use printer fonts so all fonts you use must be available on ///Fonts/Xerox/PressFonts/. Griffin keeps the old conventions for specifying font family, face and size so you name a font with a string of the form <family><pointsize><face>, ie: Helvetica10B. There is a menu under "Text Style" that shows a single font name which is the current font. To change the font select a new name and click the font menu. If Griffin can find the font the menu will change to reflect the new font, otherwise you will get a default font like Helvetica10.

Griffin provides hardcopy through Interpress files created by invoking the IP menu button. Once an Interpress file is created, it may be printed by converting it to a PD file for a specific printing device and then sending that PD file over the network to an instance of that printing device. See /Cedar/CedarChest@/Documentation/InterpressToolsDoc.tioga for details on how to make PD files.

The "Frame" button in the View menu paints a cropping frame that represents an 8.5 inch X 11.0 inch region. The frame may be moved like a menu by grabbing its edge or interior. If the frame is visible when the IP button is invoked, than the IP master will consist only of those objects within the frame, translated to fit on a standard size page.

Note that the frame is implemented as a "topmost object", so when it is on users cannot readily operate on objects underneath it. In particular, normal selection won't work. Sooo, turn the frame "on" only to check on the framing of objects and when IP is invoked if cropping is desired.

Griffin keeps a backup file. If you destroy a viewer, Destroyed.Griffin is created and contains the current contents of the destroyed Griffin viewer.

Abort the error and destroy the icon. Hopefully you will get your file saved in Destroyed.Griffin. Notify Stone.PA and Pier.PA of all errors.

This section describes the various curve fitting methods available in Griffin. In general, deciding what method of curve fitting to use is a matter of personal preference. It is not necessary to understand all five methods to use the illustrator. The default fitting method corresponds to the menu item `Natural: Arc Length', and is adequate for most pictures. This section tries to give some description and guidelines for using the various methods. It isn't really as hard as it sounds. Experimentation is strongly encouraged.

There are five methods of curve fitting available in Griffin. These include two types of natural spline (arc length and unit length), which smoothly connect a set of control points; a non-interpolating (does not draw through the control points) spline called a B-spline; an interpolating but only first-order continuous (less smooth) curve called a Catmull-Rom curve; and a very different type of curve called a Bezier curve, which uses the control points as end points (on the curve) and tangent points (off the curve) in an alternating fashion. There is a figure on /Cedar/CedarChest@/Documentation/SplineSampler.press which shows the five curve types. This figure must be printed on a press printer.

B-splines, Catmull-Rom curves, and Bezier curves are local curves. That is, a given section of the curve is affected only by the control points near that section. As a result, these curves are more symmetrical and more modifiable (since changes at one end don't affect the other end of a long curve) than natural splines. Each section of the curve is completely defined by four control points. For the B-spline and Catmull-Rom curves, moving one control point will affect four sections of the curve. For Bezier curves, moving one control point will affect only one or two sections of the curve.

Natural splines and Catmull-Rom curves are defined by placing control points along the desired curve. The algorithm will draw a curve through the points. Think of these points as handles'' to control the slant of the curve at the end conditions. (The Catmull-Rom curve does not go through the first and last control points; by placing double points at the beginning and the end, you can make the curve continue out to the endpoints.) The two types of natural spline generate similar-looking curves, especially if the control points are evenly spaced. In general, the unit mesh version will give sharper turns at the control points. The Catmull-Rom curves, in comparison, look very square. However, because they are local curves, they may be easier to use for some shapes.

The B-spline goes near all the control points but through none of them. It is defined by placing control points near the desired path; the curve follows the direction of the points, but does not pass through them. B-splines are local curves and are very smooth and symmetrical, but it is quite a bit harder to predict from the positions of the control points where the curve will fall. Placing the control points in some regular pattern using the grid will produce very attractive curves for borders or symmetrical shapes.

Each section of a Bezier curve is defined by the end points plus two points off the curve (tangent points). The control points must be placed in the following order: end point, tangent point, tangent point, end point. The line from the first end point to the first tangent point is tangent to the curve (describes the slope or slant) at the end point. Similarly, the line from the second tangent point to the second end point is tangent to the curve at the second end point. If more than four control points are placed, the first four define the first section of curve, the fourth point plus the next three define the second section of curve, and so on. The sections are connected, but not smoothly. To make a smooth connection between sections, it is necessary to line up the tangents of the two sections. That is, there must be three control points in a line at the join point. Bezier curves are useful for drawing a short section of curve when the tangents at the end conditions are important (for example, a curve that points horizontally from the side of a box into the side of another box). Bezier curves can also be used to make symmetrical or repeated shapes with sharp breaks in them.

Because Catmull-Rom curves and B-splines do not go through the first and last control points, these curves cannot be used in this version of Griffin to make objects with multiple links. Objects are also restricted to using only one method of curve fitting for the entire object. Thus it is illegal to change the curve-fitting method in the middle of a multiply-linked object.

The following is a summary of file operations used in Griffin:

The following is a summary of all menus used in Griffin and their contents: