Update xdot description;

note that dot or xdot output may create attributes that affect future
layouts

diff --git a/doc/libguide/basic.tex b/doc/libguide/basic.tex
index e340a7c516388e9c9a5a8c0729a70a6dd34e8241..45a431f2763364e8f436afc50ed91d480a3c4a10 100644 (file)
--- a/doc/libguide/basic.tex
+++ b/doc/libguide/basic.tex
@@ -912,6 +912,16 @@ information with a call to {\tt gvFreeLayout}
 before invoking a new layout function.
 An example of this was given in Figure~\ref{fig:nop}.
 
+Note that if you render a graph into the {\tt dot} or {\tt xdot}
+format, this attaches attributes onto the graph. Some of these attributes
+are used during layout. For example, the {\tt neato} layout will use
+the {\tt pos} attribute of the nodes for an initial layout, while the
+{\tt twopi} layout may set the {\tt root} attribute, which will lock in
+this attribute for any future layouts using {\tt twopi}.
+To avoid having these attributes affecting another
+layout of the graph, the user should should set these attributes to the
+empty string before calling {\tt gvLayout} again.
+
 Once the application is totally done with a graph, it should call
 {\tt agclose} to close the graph and reclaim the remaining resources associated
 with it.

diff --git a/doc/libguide/intro.tex b/doc/libguide/intro.tex
index 52f933fb7703358b3f554b42f5d08673d9e349a9..5e80bc35d1ac25a8f439a05bbf8a00dcd30be85b 100644 (file)
--- a/doc/libguide/intro.tex
+++ b/doc/libguide/intro.tex
@@ -166,6 +166,8 @@ Text drawn using the baseline point $(x,y)$. The text consists of the
 $n$ bytes following {\tt '-'}. The text should be left-aligned (centered,
 right-aligned) on the point if $j$ is -1 (0, 1), respectively. The 
 value $w$ gives the width of the text as computed by the library.  \\
+${\tt t}\ f$ &
+Set font characteristics. The integer f is the OR of BOLD=1, ITALIC=2, UNDERLINE=4, SUPERSCRIPT=8, SUBSCRIPT=16, and STRIKE-THROUGH=32. \\
 ${\tt C}\ n\ {\tt -}c_{1}c_{2}\cdots c_{n}$ & Set color used to fill closed
 regions. The
 color is specified by the $n$ characters following {\tt '-'}. \\
@@ -177,6 +179,9 @@ size is $s$ points. The font name
 is specified by the $n$ characters following {\tt '-'}. \\
 ${\tt S}\ n\ {\tt -}c_{1}c_{2}\cdots c_{n}$ & Set style attribute. The
 style value is specified by the $n$ characters following {\tt '-'}. \\
+${\tt I}\ x\ y\ j\ w\ n\ {\tt -}c_{1}c_{2}\cdots c_{n}$ &
+Externally-specified image drawn in the box with lower left corner $(x,y)$ 
+and upper right corner $(x+w,y+h)$. The name of the image consists of the $n$ bytes following '-'. This is usually a bitmap image. Note that the image size, even when converted from pixels to points, might be different from the required size $(w,h)$. It is assumed the renderer will perform the necessary scaling.\\
 \hline
 \end{tabular}
 \caption{{\tt xdot} drawing operations}

diff --git a/doc/libguide/libguide.pdf b/doc/libguide/libguide.pdf
index 11254329dbeb52cefb826a682ab789e0e883ebd3..60c6860b8d895033004911e089a026569fe8ff76 100644 (file)
Binary files a/doc/libguide/libguide.pdf and b/doc/libguide/libguide.pdf differ