Plot Language Documentation

The rend package is designed to produce a description of a CAD plot in a small language defined as follows:

Initialization
d1 d2
Two int's separated by a space and followed by a newline. This should indicate the size in pixels of the plot window. d1 is pixel size for width, d2 is pixel size for height.

Command Loop
What follows are the literal characters that are sent to indicate the type of object to be described, along with descriptions of the info following the character code.
L
Means draw a 2-level section over a 1-level sector. A single character (T/F/U) follows that indicates truth value. Then and int n giving the number of points in the polyline to follow. Then n pairs of int's giving the xy-coordinates of the points comprising the polyline.
P
Means draw a 2-level sector over a 1-level sector. A single character (T/F/U) follows that indicates truth value. Then and int n giving the number of points in the polygon to follow. Then n pairs of int's giving the xy-coordinates of the points comprising the polygon. Vertices may or may not appear twice in this list, but they will be ordered.
R
Means draw a 2-level sector over a 1-level section. A single character (T/F/U) follows that indicates truth value. Then three int's x, y1, y2. The segment with endpoints (x,y1) and (x,y2) should be produced.
V
Means draw a 1-level section. A single character (T/F/U) follows that indicates truth value. Then one int x, y1, y2. The segment with endpoints (x,-infinty) and (x,+infinity) should be produced.
C
Means draw a 1-level sector. A single character (T/F/U) follows that indicates truth value. Then two int's x1 and x2. The rectangle (x1,x2)x(-infinty,+infinity) should be produced.
S
Means draw a 2-level section over a 1-level section (i.e. a single point). A single character (T/F/U) follows that indicates truth value. Then two int's x and y. A point should be produced at coord's (x,y).
F
Refresh.
E
Means the graphics data is at an end.
This information is produced by the exceedingly ugly code in the file WRITE_PLOT.cc.
Christopher W Brown
Last modified: Mon Oct 18 18:50:59 EDT 1999