PICASSO(1) PICASSO(1)
NAME
picasso - a line drawing program
SYNOPSIS
picasso [ -bsize -Fpath -Ipath -ln -Mn -mmargin -pmxn -t -x
] [ - ] [ file_name(s) ]
DESCRIPTION
Picasso is a processor for a PIC-like drawing language that
produces PostScript output. By default, this output is
scaled to fit an 8 by 10 inch print area, and centered on
the page.
-b size specifies a buffer of size objects accumulated
before translation into PostScript. By default, an entire
picture is buffered; on machines with small memories, a
buffer of a few thousand objects can prevent thrashing when
processing a very large picture. This option is for excep-
tional cases and is not often needed.
-I path overrides the standard path for searching for the
PostScript prologue and font descriptions (not needed in
normal use).
-F path overrides the standard path for font width tables.
The default is to use the troff tables.
-l n processes layer n only, as specified by curlayer=n.
-M n magnifies the output image by n (shrinks if 0 < n < 1).
-p mxn specifies output device size in inches (8.5x11
default).
-t packages the PostScript with surrounding troff input so
that the output file may be passed down a pipeline to
troff(1). The Drechsler/Wilks mpictures macro package can
be used with troff to insert the pictures appropriately
within the document. Without the flag picasso outputs only
PostScript, dropping any text outside the markers (.PS and
.PE) delimiting each picture.
-m margin specifies an empty border, in printer's points,
that picasso will place around each picture. This may be
useful at times to prevent too tight clipping against adja-
cent text or the edge of the paper. By default no margin is
supplied; to cause a 1/8" (9 point) margin, for example,
specify -m9.
-x suppresses the default scaling and centering.
PICASSO(1) PICASSO(1)
The picasso picture description language is object oriented,
the basic objects being arrow, arc, box, circle, ellipse,
line, sector, spline, and (quoted) text. These can be com-
bined, hierarchically, into blocks. Primitive objects can
be drawn with solid, dashed, dotted, or invisible edges.
These edges may be of varying weight (thickness) and of any
shade of gray (from black = 0 to white = 1) or color. The
predefined colors are black, white, red, green, blue, cyan,
magenta, and yellow.
Objects may be named and referred to by name or by anonymous
references such as 1st box, 4th object, or 2nd last circle.
Object names require an initial upper case letter; names
beginning with lower case or an underscore are numeric vari-
ables. There are a number of predefined variables such as
circlerad, boxwid, linecolor. Picasso provides a limited
set of programming language constructs (loops, if state-
ments, macros, some arithmetic) for combining simple objects
into relatively complex pictures.
By default, objects are placed on the page adjacent to each
other and from left to right. The default direction may be
changed, and any object can be placed at a specific postion,
given either in absolute coordinates or by reference to
other objects and points of interest. Any object has a top,
bottom, left, and right point; these points may also be ref-
ered to directionally as north, south, west, and east (or n,
s, w, and e.) The ``corner'' points may also be specified,
e.g., northwest or nw. Lines have start and end points; you
may also refer to 1st, 2nd... nth points along a line.
Boxes, circles, and ellipses have eight predefined points
corresponding to the directional references mentioned above,
the first point being in the eastern direction and the 8th
point towards the southeast. For any object, the ``corner''
points really lie on the corners of a box surrounding the
object while the ``counted'' points lie on the object
itself. This distinction is normally relevant only for cir-
cles and ellipses, but since an object can be rotated or
otherwise transformed it occasionally has significance for
other objects as well.
EXAMPLE
The following is a simple no-smoking sign described in the
picasso language.
.PS
d = 0.5
[ box ht d wid 3.5 weight d/20
box ht d wid d/2 filled 0.5 noedge
spline weight 0.2 edge .75 right d then up d \
then right d then up d
]
PICASSO(1) PICASSO(1)
linecolor = red; lineweight = 0.375
circle rad 3 at last block
line from last circle .4th to last circle .8th
.PE
If this is used in a troff document and processed through
picasso with the -t flag, the .PS marking the start of the
picture can specify the size and placement of the picture at
that point in your document. For example, to place the no
smoking sign centered on the page in a 3 inch square area,
flag the start of the picture with .PS 3 3 c.
SEE ALSO
troff(1), troff(5)
REFERENCE
R. L. Drechsler and A. R. Wilks, PostScript pictures in
troff documents.
B. W. Kernighan, PIC - A Crude Graphics Language
N-P. Nelson, M. L. Siemon, Picasso 1.0, An OPEN LOOK Drawing
Program
BUGS
Picasso is not completely compatible with pic(1). Besides
having a number of new keywords and predefined variable
names, picasso also centers pictures on a page rather than
placing them at upper left.
The interactive version is unable to generate many elements
of the language, nor will it preserve such elements (e.g.,
loops) if they are read in then written out.