From fa080de7afc95aa1c19a6e6fc0e0708ced2eadc4 Mon Sep 17 00:00:00 2001
From: Joseph Hunkeler <jhunkeler@gmail.com>
Date: Wed, 8 Jul 2015 20:46:52 -0400
Subject: Initial commit

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 pkg/plot/doc/showcap.hlp | 99 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 99 insertions(+)
 create mode 100644 pkg/plot/doc/showcap.hlp

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diff --git a/pkg/plot/doc/showcap.hlp b/pkg/plot/doc/showcap.hlp
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+.help showcap Jan86 plot
+.ih
+NAME
+showcap -- show and decode graphcap entries
+.ih
+USAGE
+showcap
+.ih
+PARAMETERS
+None
+.ih
+DESCRIPTION
+\fBShowcap\fR is an interactive, parameterless task that prints and interprets
+entries in the IRAF graphics device capability file dev$graphcap.  These
+entries contain device dimensions, character sizes etc. plus information for 
+encoding and decoding the ASCII control sequences sent to or returned by the
+device.  \fBShowcap\fR is thus mainly used by IRAF programmers for debugging
+new graphcap device entries.
+
+At startup \fBshowcap\fR prints the following instructions to STDOUT, then
+prompts with an asterisk.
+.nf
+
+	cmd :  `set' device
+	    |  `*' (to dump full graphcap entry)
+	    |  cc [arg1 [arg2 [arg3]]]
+	    ;
+	
+	cc  :   a two character capcode (e.g., 'cm')
+	    |   an encoder program (non alpha first char)
+	    ;
+	*
+	
+.fi
+The user must first use `set' to tell \fBshowcap\fR which graphics device to
+read from graphcap.  After a `set' or `*', the full graphcap entry for the
+named device will be printed.  To view an individual capability, type the
+two-character capability name.
+
+Some device capability entries take up to three arguments, which may be 
+listed on the same line after `cc', separated by whitespace.  \fBShowcap\fR
+is particularly useful for decoding the binary encoder entries used by the
+graphics kernels.  See the examples below.
+.ih
+EXAMPLES
+1. Examine the graphcap entry for the Retrographics vt640.
+
+.nf
+	cl> showcap
+	  * set vt640		(dumps vt640 entry)
+.fi
+
+2. Decode the sequence sent to the terminal for setting text height 2.
+
+.nf
+	  * TH 2
+		    program:  ^[(1#47+.
+		    encoding: ^[1
+.fi
+
+3. Decode the sequence sent to the terminal to set line type 3.
+
+.nf
+	  * LT 3
+		    program:  LT=\E/(1$0)1d\E`($1-5)0d\E(1_+.$D)0d\E`($$:\
+		    encoding: ^[/0d^[b
+.fi
+
+4. Set environment variable "graphcap" to your local test graphcap file, 
+set device to vt240 and examine the write-cursor (WC) command for
+x-coordinate 150, y-coordinate 350, and cursor 1.
+
+.nf
+	cl> set graphcap = "mytest.graphcap"
+	cl> showcap
+	  * set vt240		(dumps vt240 entry)
+	  * WC 150 350 1
+		    program:  P[(1)%d,(2)%d]
+		    encoding: P[150,350]
+.fi
+
+5. Examine the scan-cursor function returned when the user types key `a'
+from coordinate x=150, y=350 after a read-cursor request.
+
+.nf
+	  * SC a[150,350]
+		    program:  (#0!1#0!2,!3,#0!8,#48-!99$0-91#10*9+!1#1!8
+			      $$8#1=#-39;#0!8,#48-!99$0-92#10*9+!2#1!8
+			      $$8#1=#-39;);
+		    X(R1)=150 Y(R2)=350, key = a
+.fi
+.ih
+BUGS
+Diagnostics are mostly limited to a numeric status return when debugging
+binary encoder entries that contain bugs.
+.ih
+SEE ALSO
+Graphics I/O Design Document.
+.endhelp
-- 
cgit