### PICDEF

Defines a new graphics-database FRAME picture or an array of FRAME pictures

#### Description:

This application creates either one new graphics-database  FRAME picture or a grid of new FRAME pictures. It offers a variety of ways by which you can define a new picture’s location and extent. You may constrain a new picture to lie within either the current or the BASE picture, and the new picture adopts the world co-ordinate system of that reference picture.

You may specify a single new picture using one of three methods: 1. moving a cursor to define the lower and upper bounds via pressing choice number 1 (the application will instruct what to do for the specific graphics device), provided a cursor is available on the chosen graphics workstation; 2. obtaining the bounds from the environment (in world co-ordinates of the reference picture); 3. or by giving a position and size for the new picture. The position is specified by a two-character code. The first controls the vertical location, and may be "T", "B", or "C" to create the new picture at the top, bottom, or in the centre respectively. The second defines the horizontal situation, and may be "L", "R", or "C" to define a new picture to the left, right, or in the centre respectively. Thus a code of "BR" will make a new picture in the bottom-right corner. The size of the new picture along each axis may be specified either in centimetres, or as a fraction of the corresponding axis of the reference picture. The picture may also be forced to have a specified aspect ratio.

The picture created becomes the current picture on exit.

Alternatively, you can create an array of n-by-m equal-sized pictures by giving the number of pictures in the horizontal and vertical directions. These may or may not be abutted. For easy reference in later processing the pictures may be labelled automatically. The label consists of a prefix you define, followed by the number of the picture. The numbering starts at a defined value, usually one, and increments by one for each new picture starting from the bottom-left corner and moving from left to right to the end of the line. This is repeated in each line until the top-right picture. Thus if the prefix were "GALAXY", the start number is one and the array comprises three pictures horizontally and two vertically, the top-left picture would have the label "GALAXY4". On completion the bottom-left picture in the array becomes the current picture.

#### Usage:

picdef [mode] [fraction] $\left\{\right\$
xpic ypic prefix=? lbound=? ubound=?

mode

#### Parameters:

The aspect ratio (x/y) of the picture to be created in modes other than Cursor, Array, and XY. The new picture is the largest possible with the chosen aspect ratio that will fit within the part of the reference picture defined by the fractional sizes (see Parameter FRACTION). The justification comes from the value of MODE. Thus to obtain the largest picture, set FRACTION=1.0. A null value (!) does not apply an aspect-ratio constraint, and therefore the new picture fills the part of the reference picture defined by the fractional sizes. [!]
TRUE if the new picture is to lie within the current picture, otherwise the new picture can lie anywhere within the BASE picture. In other words, when it is TRUE the current picture is the reference picture, and when FALSE, the base is the reference picture. [FALSE]
The graphics device. [Current graphics device]
The linear filling factor for the Array mode. In other words the fractional size (applied to both co-ordinates) of the new picture within each of the XPIC $\ast$ YPIC abutted sections of the picture being sub-divided. Each new picture is located centrally within the section. A filling factor of 1.0 means that the pictures in the array abut. Smaller factors permit a gap between the pictures. For example, FILL = 0.9 would give a gap between the created pictures of 10 per cent of the height and width of each picture, with exterior borders of 5 per cent. FILL must lie between 0.1 and 1.0. [1.0]
##### FRACTION( ) = _REAL (Read)
The fractional size of the new picture along each axis, applicable for modes other than Array, Cursor, and XY. Thus FRACTION controls the relative shape as well as the size of the new picture. If only a single value is given then it is applied to both x and y axes, whereupon the new picture has the shape of the reference picture. So a value of 0.5 would create a picture 0.25 the area of the current or BASE picture. The default is 0.5, unless Parameter ASPECT is not null, when the default is 1.0. This parameter is not used if the picture size is specified in centimetres using Parameter SIZE. []
The number used to form the label for the first (bottom-left) picture in Array mode. It cannot be negative. [1]
##### LBOUND( 2 ) = _REAL (Read)
Co-ordinates of the lower bound that defines the new picture. The suggested default is the bottom-left of the current picture. (XY mode)
Method for selecting the new picture. The options are "Cursor" for cursor mode (provided the graphics device has one), "XY" to select x-y limits, and "Array" to create a grid of equal-sized FRAME pictures. The remainder are locations specified by two characters, the first corresponding to the vertical position and the second the horizontal. For the vertical, valid positions are T(op), B(ottom), or C(entre); and for the horizontal the options are L(eft), R(ight), or C(entre). ["Cursor"]
If TRUE, a box that delimits the new picture is drawn. [TRUE]
The prefix to be given to the labels of picture created in Array mode. It should contain no more than twelve characters. If the empty string "" is given, the pictures will have enumerated labels. Note that the database can contain only one picture with a given label, and so merely numbering labels increases the chance of losing existing labels. A ! response means no labelling is required. The suggested default is the last-used prefix.
##### SIZE( 2 ) = _REAL (Read)
The size of the new picture along both axes, in centimetres, applicable for modes other than Array, Cursor, and XY. If a single value is given, it is used for both axes. If a null value (!) is given, then the size of the picture is determined by Parameter FRACTION. [!]
##### UBOUND( 2 ) = _REAL (Read)
Co-ordinates of the upper bound that defines the new picture. The suggested default is the top-right of the current picture. (XY mode)
The number of new pictures to be formed horizontally in the BASE or current picture in Array mode. The total number of new pictures is XPIC $\ast$ YPIC. The value must lie in the range 1–20. The suggested default is 2.
The number of new pictures to be formed vertically in the BASE or current picture in Array mode. The value must lie in the range 1–20. The suggested default is the value of Parameter XPIC.

#### Examples:

picdef tr
Creates a new FRAME picture in the top-right quarter of the full display area on the current graphics device, and an outline is drawn around the new picture. This picture becomes the current picture.
picdef bl aspect=1.0
Creates a new FRAME picture within the full display area on the current graphics device, and an outline is drawn around the new picture. This picture is the largest square possible, and it is justified to the bottom-left corner. It becomes the current picture.
picdef bl size=[15,10]
Creates a new FRAME picture within the full display area on the current graphics device, and an outline is drawn around the new picture. This picture is 15 by 10 centimetres in size and it is justified to the bottom-left corner. It becomes the current picture.
picdef cc 0.7 current nooutline
Creates a new FRAME picture situated in the centre of the current picture on the current graphics device. The new picture has the same shape as the current one, but it is linearly reduced by a factor of 0.7. No outline is drawn around it. The new picture becomes the current picture.
picdef cc [0.8,0.5] current nooutline
As above except that its height is half that of the current picture, and its width is 0.8 of the current picture.
picdef cu device=graphon
Creates a new FRAME picture within the full display area of the Graphon device. The bounds of the new picture are defined by cursor interaction. An outline is drawn around the new picture which becomes the current picture.
picdef mode=a prefix=M xpic=3 ypic=2
Creates six new equally sized and abutting FRAME pictures within the full display area of the current graphics device. All are outlined. They have labels M1, M2, M3, M4, M5, and M6. The bottom-left picture (M1) becomes the current picture.
picdef mode=a prefix="" xpic=3 ypic=2 fill=0.8
As above except that the pictures do not abut since each is 0.8 times smaller in both dimensions, and the labels are 1, 2, 3, 4, 5, and 6.