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