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authorJeffrey H. Kingston <jeff@it.usyd.edu.au>2010-09-14 19:21:41 +0000
committerJeffrey H. Kingston <jeff@it.usyd.edu.au>2010-09-14 19:21:41 +0000
commit71bdb35d52747e6d7d9f55df4524d57c2966be94 (patch)
tree480ee5eefccc40d5f3331cc52d66f722fd19bfb9 /doc/user/dia_summ
parentb41263ea7578fa9742486135c762803b52794105 (diff)
downloadlout-71bdb35d52747e6d7d9f55df4524d57c2966be94.tar.gz
Lout 3.17.
git-svn-id: http://svn.savannah.nongnu.org/svn/lout/trunk@2 9365b830-b601-4143-9ba8-b4a8e2c3339c
Diffstat (limited to 'doc/user/dia_summ')
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1 files changed, 1680 insertions, 0 deletions
diff --git a/doc/user/dia_summ b/doc/user/dia_summ
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+@Section
+ @Tag { dia_summ }
+ @Title { Summary }
+@Begin
+@PP
+Here is the complete list of standard node outlines that may be given
+to the @Code "@Node" symbol. Each shows the outline name, any extra
+options relevant to this outline, base (shown as a grey
+box), segments (shown using {@Code "outlinestyle { solid dashed }"}),
+tags, and directions (shown as a thick arrowhead wherever defined):
+@IndentedList gap { 3v }
+
+@LI {
+@Code {
+"@Node"
+" outline { box }"
+}
+||7ct
+@Diag {
+//0.5f
+@Box paint { lightgrey } outlinestyle { noline } margin { 0c }
+@ShowTags @ShowDirections @Node
+ outline { box }
+ outlinestyle { solid dashed }
+ outlinewidth { 0.03f }
+ vsize { 1.0c } hsize { 2.0c }
+}
+}
+
+@LI {
+@Code {
+"@Node"
+" outline { curvebox }"
+}
+||7ct
+@Diag {
+@Box paint { lightgrey } outlinestyle { noline } margin { 0c }
+@ShowTags @ShowDirections @Node
+ outline { curvebox }
+ outlinestyle { solid dashed }
+ outlinewidth { 0.03f }
+ vsize { 1.0c } hsize { 2.0c }
+}
+}
+
+@LI {
+@Code {
+"@Node"
+" outline { shadowbox }"
+" shadow { 0.4f }"
+}
+||7ct
+@Diag {
+@Box paint { lightgrey } outlinestyle { noline } margin { 0c }
+@ShowTags @ShowDirections @Node
+ outline { shadowbox }
+ outlinestyle { solid dashed }
+ outlinewidth { 0.03f }
+ vsize { 1.0c } hsize { 2.0c }
+}
+}
+
+@LI {
+@Code {
+"@Node"
+" outline { square }"
+}
+||7ct
+@Diag {
+//1.5f
+@Box paint { lightgrey } outlinestyle { noline } margin { 0c }
+@ShowTags @ShowDirections @Node
+ outline { square }
+ outlinestyle { solid dashed }
+ outlinewidth { 0.03f }
+ vsize { 1.0c } hsize { 2.0c }
+}
+}
+
+@LI {
+@Code {
+"@Node"
+" outline { diamond }"
+}
+||7ct
+@Diag {
+@Box paint { lightgrey } outlinestyle { noline } margin { 0c }
+@ShowTags @ShowDirections @Node
+ outline { diamond }
+ outlinestyle { solid dashed }
+ outlinewidth { 0.03f }
+ vsize { 1.0c } hsize { 2.0c }
+}
+}
+
+@LI {
+@Code {
+"@Node"
+" outline { polygon }"
+" sides { 3 }"
+" angle { 180d / sides }"
+}
+||7ct
+@Diag {
+//0.5f
+@Box paint { lightgrey } outlinestyle { noline } margin { 0c }
+@ShowTags @ShowDirections @Node
+ outline { polygon }
+ outlinestyle { solid dashed }
+ outlinewidth { 0.03f }
+ vsize { 1.0c } hsize { 2.0c }
+&0.5c ... &0.5c
+@Box paint { lightgrey } outlinestyle { noline } margin { 0c }
+@ShowTags @ShowDirections @Node
+ outline { polygon }
+ sides { 10 }
+ outlinestyle { solid dashed }
+ outlinewidth { 0.03f }
+ vsize { 1.0c } hsize { 2.0c }
+&0.5c ...
+}
+}
+
+@LI {
+@Code {
+"@Node"
+" outline { isosceles }"
+}
+||7ct
+@Diag {
+@Box paint { lightgrey } outlinestyle { noline } margin { 0c }
+@ShowTags @ShowDirections @Node
+ outline { isosceles }
+ outlinestyle { solid dashed }
+ outlinewidth { 0.03f }
+ vsize { 1.0c } hsize { 2.0c }
+}
+}
+
+@LI {
+@Code {
+"@Node"
+" outline { ellipse }"
+}
+||7ct
+@Diag {
+@Box paint { lightgrey } outlinestyle { noline } margin { 0c }
+@ShowTags @ShowDirections @Node
+ outline { ellipse }
+ outlinestyle { solid dashed }
+ outlinewidth { 0.03f }
+ vsize { 1.0c } hsize { 2.0c }
+}
+}
+
+@LI {
+@Code {
+"@Node"
+" outline { circle }"
+}
+||7ct
+@Diag {
+@Box paint { lightgrey } outlinestyle { noline } margin { 0c }
+@ShowTags @ShowDirections @Node
+ outline { circle }
+ outlinestyle { solid dashed }
+ outlinewidth { 0.03f }
+ vsize { 1.0c } hsize { 2.0c }
+}
+}
+
+@EndList
+@DP
+Here are the abbreviations for the standard shapes:
+@ID @Tab
+ vmargin { 0.5vx }
+ @Fmta { @Col @Code { outline "{" A "}" } ! @Col @Code { "@"B } }
+{
+@Rowa
+ A { box }
+ B { Box }
+@Rowa
+ A { curvebox }
+ B { CurveBox }
+@Rowa
+ A { shadowbox }
+ B { ShadowBox }
+@Rowa
+ A { square }
+ B { Square }
+@Rowa
+ A { diamond }
+ B { Diamond }
+@Rowa
+ A { polygon }
+ B { Polygon }
+@Rowa
+ A { isosceles }
+ B { Isosceles }
+@Rowa
+ A { ellipse }
+ B { Ellipse }
+@Rowa
+ A { circle }
+ B { Circle }
+}
+Here are all the options to the @Code "@Node" symbol, their default
+values, and their ranges of allowed values. Definitions of {@I number},
+{@I length}, {@I angle}, and {@I point} appear later in this summary. The
+options related to {@Code alabel}, {@Code blabel}, {@Code clabel}, and
+{@Code dlabel} have mostly been omitted since they are the same as
+the {@Code nodelabel} options except for {@Code nodelabelpos}.
+@DP
+1fx @Break @Tab
+ hmargin { 1s }
+ # vmargin { 0.6vx }
+ @Fmth { @Col @Code A ! @Col @Code " " ! @Col @Code B ! @Col @Code " " !
+ @Col 1.0c @Wide ! @Col C }
+ @Fmta { @Col @Code A ! @Col @Code "{" ! @Col @Code B ! @Col @Code "}" !
+ @Col 1.0c @Wide ! @Col C }
+{
+@FirstRowh
+ A { "@Node" }
+@Rowa
+ A { " outline" }
+ B { box }
+ C { {@Code box}, {@Code curvebox}, {@Code shadowbox}, {@Code square},
+{@Code diamond}, {@Code polygon}, {@Code ellipse}, {@Code circle}, or
+any outline }
+@Rowa
+ A { " margin" }
+ B { 0.6f }
+ C { any length from Section {@NumberOf objects} }
+@Rowa
+ A { " shadow" }
+ B { 0.4f }
+ C { any @I length }
+@Rowa
+ A { " sides" }
+ B { 3 }
+ C { any @I number (it will be rounded to the nearest integer) }
+@Rowa
+ A { " angle" }
+ B { 180d "/" sides }
+ C { any @I angle }
+@Rowa
+ A { " translate" }
+ B { }
+ C { empty, or @I point @Code to @I point }
+@Rowa
+ A { " outlinestyle" }
+ B { solid }
+ C { {@Code solid}, {@Code dashed}, {@Code cdashed}, {@Code dotted},
+{@Code noline}, or any sequence of one or more of these values }
+@Rowa
+ A { " outlinedashlength"}
+ B { 0.2f }
+ C { any @I length }
+@Rowa
+ A { " outlinewidth" }
+ B { thin }
+ C { {@Code thin}, {@Code medium}, {@Code thick}, or any @I length }
+@Rowa
+ A { " paint" }
+ B { nopaint }
+ C { @Code nopaint or any colour from Section {@NumberOf colour} }
+@Rowa
+ A { " font" }
+ B { }
+ C { any value suitable for the @Code "@Font" symbol }
+@Rowa
+ A { " break" }
+ B { }
+ C { any value suitable for the @Code "@Break" symbol }
+@Rowa
+ A { " format" }
+ B { "@Body" }
+ C { any object, usually containing {@Code "@Body"} }
+@Rowa
+ A { " valign"}
+ B { ctr }
+ C { {@Code "top"}, {@Code "ctr"}, {@Code "foot"}, or any length
+from Section {@NumberOf objects} }
+@Rowa
+ A { " vsize"}
+ B { }
+ C { empty, or any length from Section {@NumberOf objects} }
+@Rowa
+ A { " vindent"}
+ B { ctr }
+ C { {@Code "top"}, {@Code "ctr"}, {@Code "mctr"}, {@Code "foot"}, or any
+length from Section {@NumberOf objects} }
+@Rowa
+ A { " vstrut"}
+ B { no }
+ C { {@Code no}, {@Code yes}, or any length from Section {@NumberOf objects} }
+@Rowa
+ A { " vmargin" }
+ B { margin }
+ C { any length from Section {@NumberOf objects} }
+@Rowa
+ A { " topmargin" }
+ B { vmargin }
+ C { any length from Section {@NumberOf objects} }
+@Rowa
+ A { " footmargin" }
+ B { vmargin }
+ C { any length from Section {@NumberOf objects} }
+@Rowa
+ A { " halign"}
+ B { ctr }
+ C { {@Code "left"}, {@Code "ctr"}, {@Code "right"}, or any length from Section {@NumberOf objects} }
+@Rowa
+ A { " hsize"}
+ B { }
+ C { empty, or any length from Section {@NumberOf objects} }
+@Rowa
+ A { " hindent"}
+ B { ctr }
+ C { {@Code "left"}, {@Code "ctr"}, {@Code "mctr"}, {@Code "right"}, or any
+length from Section {@NumberOf objects} }
+@Rowa
+ A { " hmargin" }
+ B { margin }
+ C { any length from Section {@NumberOf objects} }
+@Rowa
+ A { " leftmargin" }
+ B { hmargin }
+ C { any length from Section {@NumberOf objects} }
+@Rowa
+ A { " rightmargin" }
+ B { hmargin }
+ C { any length from Section {@NumberOf objects} }
+@Rowa
+ A { " hstrut"}
+ B { no }
+ C { {@Code no}, {@Code yes}, or any length from Section {@NumberOf objects} }
+@Rowa
+ A { " nodelabel"}
+ B { }
+ C { any object }
+@Rowa
+ A { " nodelabelmargin"}
+ B { 0.2f }
+ C { any length from Section {@NumberOf objects} }
+@Rowa
+ A { " nodelabelfont"}
+ B { -2p }
+ C { any value suitable for the @Code "@Font" symbol }
+@Rowa
+ A { " nodelabelbreak"}
+ B { ragged nohyphen }
+ C { any value suitable for the @Code "@Break" symbol }
+@Rowa
+ A { " nodelabelformat"}
+ B { "@Body" }
+ C { any object, usually containing @Code "@Body" }
+@Rowa
+ A { " nodelabelpos"}
+ B { }
+ C { any @I point }
+@Rowa
+ A { " nodelabelangle"}
+ B { horizontal }
+ C { {@Code horizontal}, {@Code aligned}, or {@Code perpendicular};
+{@Code parallel}, {@Code antiparallel}, or any @I angle }
+@Rowa
+ A { " nodelabelprox"}
+ B { outside }
+ C { {@Code above}, {@Code below}, {@Code left}, {@Code right},
+{@Code inside}, or {@Code outside}; {@Code CTR}, {@Code N}, {@Code S},
+{@Code E}, {@Code W}, {@Code NE}, {@Code NW}, {@Code SW}, or {@Code SE}
+}
+@Rowa
+ A { " nodelabelctr"}
+ B { no }
+ C { @Code yes or @Code no }
+@Rowa
+ A { " nodelabeladjust"}
+ B { 0 0 }
+ C { any @I point }
+@Rowa
+ A { " alabelpos"}
+ B { NE }
+ C { any @I point }
+@Rowa
+ A { " blabelpos"}
+ B { NW }
+ C { any @I point }
+@Rowa
+ A { " clabelpos"}
+ B { SW }
+ C { any @I point }
+@Rowa
+ A { " dlabelpos"}
+ B { SE }
+ C { any @I point }
+}
+@DP
+Here is the complete list of standard link paths that may be given
+to the @Code "@Link" symbol. Each entry shows the link path name,
+any extra options relevant to this path, segments (shown using
+{@Code "outlinestyle { solid dashed }"}, and tags. All tags
+have directions pointing along the link from @Code FROM to
+{@Code TO}; these have been omitted for clarity. The @Code frompt
+and @Code topt options of @Code bezier are compulsory and denote the
+two control points (Section {@NumberOf dia_defi}).
+@IndentedList gap { 2v }
+
+@LI {
+@Code {
+"@Link"
+" path { line }"
+}
+||6ct
+@Diag {
+//0.5f
+A:: @Circle /0.8c |1.5c B:: @Circle
+//
+@ShowTags @Link
+ pathstyle { solid dashed }
+ path { line } from { A } to { B }
+}
+&2.5c
+#@Diag {
+#|1.5c B:: @Circle /0.8c A:: @Circle
+#//
+#@ShowTags @Link
+# pathstyle { solid dashed }
+# path { line } from { A } to { B }
+#}
+}
+
+@LI {
+@Code {
+"@Link"
+" path { doubleline }"
+}
+||6ct
+@Diag {
+//0.5f
+A:: @Circle /0.8c |1.5c B:: @Circle
+//
+@ShowTags @Link
+ pathstyle { solid dashed }
+ path { doubleline } from { A } to { B }
+}
+&2.5c
+#@Diag {
+#|1.5c B:: @Circle /0.8c A:: @Circle
+#//
+#@ShowTags @Link
+# pathstyle { solid dashed }
+# path { line } from { A } to { B }
+#}
+}
+
+@LI {
+@Code {
+"@Link"
+" path { curve }"
+" bias { 2.0f }"
+}
+||6ct
+@Diag {
+A:: @Circle /0.8c |1.5c B:: @Circle
+//
+@ShowTags @Link
+ pathstyle { solid dashed }
+ path { curve } from { A } to { B }
+}
+&2.5c
+@Diag {
+|1.5c B:: @Circle /0.8c A:: @Circle
+//
+@ShowTags @Link
+ pathstyle { solid dashed }
+ path { curve } from { A } to { B }
+}
+}
+
+@LI {
+@Code {
+"@Link"
+" path { ccurve }"
+" bias { 2.0f }"
+}
+||6ct
+@Diag {
+//0.5f
+A:: @Circle /0.8c |1.5c B:: @Circle
+//
+@ShowTags @Link
+ pathstyle { solid dashed }
+ path { ccurve } from { A } to { B }
+}
+&2.5c
+@Diag {
+//0.5f
+|1.5c B:: @Circle /0.8c A:: @Circle
+//
+@ShowTags @Link
+ pathstyle { solid dashed }
+ path { ccurve } from { A } to { B }
+}
+}
+
+@LI {
+@Code {
+"@Link"
+" path { bezier }"
+" frompt { A@CTR ++ { 3f 0 } }"
+" topt { B@CTR ++ { 3f 0 } }"
+}
+||6ct
+@Diag {
+//0.5f
+A:: @Circle /0.8c |1.5c B:: @Circle
+//
+@ShowTags @Link
+ pathstyle { solid dashed }
+ path { bezier } from { A } to { B }
+ frompt { A@CTR ++ { 3f 0 } }
+ topt { B@CTR ++ { 3f 0 } }
+}
+&2.5c
+@Diag {
+//0.5f
+|1.5c B:: @Circle /0.8c A:: @Circle
+//
+@ShowTags @Link
+ pathstyle { solid dashed }
+ path { bezier } from { A } to { B }
+ frompt { A@CTR ++ { 3f 0 } }
+ topt { B@CTR ++ { 3f 0 } }
+}
+}
+
+@LI {
+@Code {
+"@Link"
+" path { vhline }"
+}
+||6ct
+@Diag {
+//0.5f
+A:: @Circle /0.8c |1.5c B:: @Circle
+//
+@ShowTags @Link
+ pathstyle { solid dashed }
+ path { vhline } from { A } to { B }
+}
+&2.5c
+@Diag {
+//0.5f
+|1.5c B:: @Circle /0.8c A:: @Circle
+//
+@ShowTags @Link
+ pathstyle { solid dashed }
+ path { vhline } from { A } to { B }
+}
+}
+
+@LI {
+@Code {
+"@Link"
+" path { hvline }"
+}
+||6ct
+@Diag {
+//0.5f
+A:: @Circle /0.8c |1.5c B:: @Circle
+//
+@ShowTags @Link
+ pathstyle { solid dashed }
+ path { hvline } from { A } to { B }
+}
+&2.5c
+@Diag {
+//0.5f
+|1.5c B:: @Circle /0.8c A:: @Circle
+//
+@ShowTags @Link
+ pathstyle { solid dashed }
+ path { hvline } from { A } to { B }
+}
+}
+
+@LI {
+@Code {
+"@Link"
+" path { vhcurve }"
+" radius { 1.0f }"
+}
+||6ct
+@Diag {
+//0.5f
+A:: @Circle /0.8c |1.5c B:: @Circle
+//
+@ShowTags @Link
+ pathstyle { solid dashed }
+ path { vhcurve } from { A } to { B }
+}
+&2.5c
+@Diag {
+//0.5f
+|1.5c B:: @Circle /0.8c A:: @Circle
+//
+@ShowTags @Link
+ pathstyle { solid dashed }
+ path { vhcurve } from { A } to { B }
+}
+}
+
+@LI {
+@Code {
+"@Link"
+" path { hvcurve }"
+" radius { 1.0f }"
+}
+||6ct
+@Diag {
+//0.5f
+A:: @Circle /0.8c |1.5c B:: @Circle
+//
+@ShowTags @Link
+ pathstyle { solid dashed }
+ path { hvcurve } from { A } to { B }
+}
+&2.5c
+@Diag {
+//0.5f
+|1.5c B:: @Circle /0.8c A:: @Circle
+//
+@ShowTags @Link
+ pathstyle { solid dashed }
+ path { hvcurve } from { A } to { B }
+}
+}
+
+@LI {
+@Code {
+"@Link"
+" path { lvrline }"
+" bias { 2.0f }"
+}
+||6ct
+@Diag {
+//0.5f
+A:: @Circle /0.8c |1.5c B:: @Circle
+//
+@ShowTags @Link
+ pathstyle { solid dashed }
+ path { lvrline } from { A } to { B }
+}
+&2.5c
+@Diag {
+//0.5f
+|1.5c B:: @Circle /0.8c A:: @Circle
+//
+@ShowTags @Link
+ pathstyle { solid dashed }
+ path { lvrline } from { A } to { B }
+}
+}
+
+@LI {
+@Code {
+"@Link"
+" path { rvlline }"
+" bias { 2.0f }"
+}
+||6ct
+@Diag {
+//0.5f
+A:: @Circle /0.8c |1.5c B:: @Circle
+//
+@ShowTags @Link
+ pathstyle { solid dashed }
+ path { rvlline } from { A } to { B }
+}
+&2.5c
+@Diag {
+//0.5f
+|1.5c B:: @Circle /0.8c A:: @Circle
+//
+@ShowTags @Link
+ pathstyle { solid dashed }
+ path { rvlline } from { A } to { B }
+}
+}
+
+@LI {
+@Code {
+"@Link"
+" path { lvrcurve }"
+" bias { 2.0f }"
+" radius { 1.0f }"
+}
+||6ct
+@Diag {
+//0.5f
+A:: @Circle /0.8c |1.5c B:: @Circle
+//
+@ShowTags @Link
+ pathstyle { solid dashed }
+ path { lvrcurve } from { A } to { B }
+}
+&2.5c
+@Diag {
+//0.5f
+|1.5c B:: @Circle /0.8c A:: @Circle
+//
+@ShowTags @Link
+ pathstyle { solid dashed }
+ path { lvrcurve } from { A } to { B }
+}
+}
+
+@LI {
+@Code {
+"@Link"
+" path { rvlcurve }"
+" bias { 2.0f }"
+" radius { 1.0f }"
+}
+||6ct
+@Diag {
+//0.5f
+A:: @Circle /0.8c |1.5c B:: @Circle
+//
+@ShowTags @Link
+ pathstyle { solid dashed }
+ path { rvlcurve } from { A } to { B }
+}
+&2.5c
+@Diag {
+//0.5f
+|1.5c B:: @Circle /0.8c A:: @Circle
+//
+@ShowTags @Link
+ pathstyle { solid dashed }
+ path { rvlcurve } from { A } to { B }
+}
+}
+
+@LI {
+@Code {
+"@Link"
+" path { dwrapline }"
+" tbias { 2.0f }"
+" bias { 2.0f }"
+" fbias { 2.0f }"
+}
+||6ct
+@Diag {
+//0.5f
+A:: @Circle /0.8c |1.5c B:: @Circle /2f
+//
+@ShowTags @Link
+ pathstyle { solid dashed }
+ path { dwrapline } from { A } to { B }
+}
+&2.5c
+@Diag {
+//0.5f
+|1.5c B:: @Circle /0.8c A:: @Circle /2f
+//
+@ShowTags @Link
+ pathstyle { solid dashed }
+ path { dwrapline } from { A } to { B }
+}
+}
+
+@LI {
+@Code {
+"@Link"
+" path { uwrapline }"
+" tbias { 2.0f }"
+" bias { 2.0f }"
+" fbias { 2.0f }"
+}
+||6ct
+@Diag {
+//0.5f
+/2f A:: @Circle /0.8c |1.5c B:: @Circle
+//
+@ShowTags @Link
+ pathstyle { solid dashed }
+ path { uwrapline } from { A } to { B }
+}
+&2.5c
+@Diag {
+//0.5f
+/2f |1.5c B:: @Circle /0.8c A:: @Circle
+//
+@ShowTags @Link
+ pathstyle { solid dashed }
+ path { uwrapline } from { A } to { B }
+}
+}
+
+@LI {
+@Code {
+"@Link"
+" path { dwrapcurve }"
+" tbias { 2.0f }"
+" bias { 2.0f }"
+" fbias { 2.0f }"
+" radius { 1.0f }"
+}
+||6ct
+@Diag {
+//0.5f
+A:: @Circle /0.8c |1.5c B:: @Circle /2f
+//
+@ShowTags @Link
+ pathstyle { solid dashed }
+ path { dwrapcurve } from { A } to { B }
+}
+&2.5c
+@Diag {
+//0.5f
+|1.5c B:: @Circle /0.8c A:: @Circle /2f
+//
+@ShowTags @Link
+ pathstyle { solid dashed }
+ path { dwrapcurve } from { A } to { B }
+}
+}
+
+@LI {
+@Code {
+"@Link"
+" path { uwrapcurve }"
+" tbias { 2.0f }"
+" bias { 2.0f }"
+" fbias { 2.0f }"
+" radius { 1.0f }"
+}
+||6ct
+@Diag {
+//0.5f
+/2f A:: @Circle /0.8c |1.5c B:: @Circle
+//
+@ShowTags @Link
+ pathstyle { solid dashed }
+ path { uwrapcurve } from { A } to { B }
+}
+&2.5c
+@Diag {
+//0.5f
+/2f |1.5c B:: @Circle /0.8c A:: @Circle
+//
+@ShowTags @Link
+ pathstyle { solid dashed }
+ path { uwrapcurve } from { A } to { B }
+}
+}
+
+@EndList
+Here is the list of abbreviations for the standard paths (note
+that @Code curve and @Code acurve are the same). Each
+path also has an abbreviation which adds a forward arrow:
+@ID @Tab
+ @Fmta { @Col @Code { path "{" A "}" } ! @Col @Code "@"B ! @Col @Code "@"C }
+{
+@Rowa
+ A { line }
+ B { Line }
+ C { Arrow }
+@Rowa
+ A { doubleline }
+ B { DoubleLine }
+ C { DoubleArrow }
+@Rowa
+ A { curve }
+ B { Curve }
+ C { CurveArrow }
+@Rowa
+ A { acurve }
+ B { ACurve }
+ C { ACurveArrow }
+@Rowa
+ A { ccurve }
+ B { CCurve }
+ C { CCurveArrow }
+
+@Rowa
+ A { bezier }
+ B { Bezier }
+ C { BezierArrow }
+
+@Rowa
+ A { hvline }
+ B { HVLine }
+ C { HVArrow }
+@Rowa
+ A { vhline }
+ B { VHLine }
+ C { VHArrow }
+@Rowa
+ A { hvcurve }
+ B { HVCurve }
+ C { HVCurveArrow }
+@Rowa
+ A { vhcurve }
+ B { VHCurve }
+ C { VHCurveArrow }
+
+@Rowa
+ A { lvrline }
+ B { LVRLine }
+ C { LVRArrow }
+@Rowa
+ A { rvlline }
+ B { RVLLine }
+ C { RVLArrow }
+@Rowa
+ A { lvrcurve }
+ B { LVRCurve }
+ C { LVRCurveArrow }
+@Rowa
+ A { rvlcurve }
+ B { RVLCurve }
+ C { RVLCurveArrow }
+
+@Rowa
+ A { dwrapline }
+ B { DWrapLine }
+ C { DWrapArrow }
+@Rowa
+ A { uwrapline }
+ B { UWrapLine }
+ C { UWrapArrow }
+@Rowa
+ A { dwrapcurve }
+ B { DWrapCurve }
+ C { DWrapCurveArrow }
+@Rowa
+ A { uwrapcurve }
+ B { UWrapCurve }
+ C { UWrapCurveArrow }
+}
+Here is the complete list of options to the @Code "@Link" symbol. The
+options related to {@Code xlabel}, {@Code ylabel}, and {@Code zlabel}
+have been omitted where they are the same as the {@Code linklabel} options.
+@DP
+1fx @Break @Tab
+ hmargin { 1s }
+ # vmargin { 0.6vx }
+ @Fmth { @Col @Code A ! @Col @Code " " ! @Col @Code B ! @Col @Code " " !
+ @Col 1.0c @Wide ! @Col C }
+ @Fmta { @Col @Code A ! @Col @Code "{" ! @Col @Code B ! @Col @Code "}" !
+ @Col 1.0c @Wide ! @Col C }
+{
+@Rowh
+ A { "@Link" }
+@Rowa
+ A { " path" }
+ B { line }
+ C { {@Code "line"}, {@Code "doubleline"}, {@Code "curve"}, {@Code "acurve"},
+{@Code "ccurve"}, {@Code "bezier"},
+{@Code "vhline"}, {@Code "hvline"}, {@Code "vhcurve"}, {@Code "hvcurve"},
+{@Code "lvrline"}, {@Code "rvlline"}, {@Code "lvrcurve"}, {@Code "rvlcurve"},
+{@Code "dwrapline"}, {@Code "uwrapline"}, {@Code "dwrapcurve"},
+{@Code "uwrapcurve"}, or any path }
+@Rowa
+ A { " from"}
+ B { 0,0 }
+ C { any @I point or node label }
+@Rowa
+ A { " to"}
+ B { 1,1 }
+ C { any @I point or node label }
+@Rowa
+ A { " bias"}
+ B { 2.0f }
+ C { any @I length }
+@Rowa
+ A { " fbias"}
+ B { 2.0f }
+ C { any @I length }
+@Rowa
+ A { " tbias"}
+ B { 2.0f }
+ C { any @I length }
+@Rowa
+ A { " radius"}
+ B { 1.0f }
+ C { any @I length }
+@Rowa
+ A { " xindent"}
+ B { 0.8f }
+ C { any @I length }
+@Rowa
+ A { " zindent"}
+ B { 0.8f }
+ C { any @I length }
+@Rowa
+ A { " frompt"}
+ B { 0 0 }
+ C { any @I point }
+@Rowa
+ A { " topt"}
+ B { 0 0 }
+ C { any @I point }
+@Rowa
+ A { " pathstyle" }
+ B { solid }
+ C { {@Code solid}, {@Code dashed}, {@Code cdashed}, {@Code dotted},
+{@Code noline}, or any sequence of one or more of these values }
+@Rowa
+ A { " pathdashlength"}
+ B { 0.2f }
+ C { any @I length }
+@Rowa
+ A { " pathwidth" }
+ B { thin }
+ C { {@Code thin}, {@Code medium}, {@Code thick}, or any @I length }
+@Rowa
+ A { " pathgap" }
+ B { thin }
+ C { {@Code thin}, {@Code medium}, {@Code thick}, or any @I length }
+@Rowa
+ A { " arrow"}
+ B { no }
+ C { {@Code no}, {@Code yes}, {@Code forward}, {@Code back},
+or {@Code both} }
+@Rowa
+ A { " arrowstyle"}
+ B { solid }
+ C { {@Code solid}, {@Code halfopen}, {@Code open}, {@Code curvedsolid},
+{@Code curvedhalfopen}, or {@Code curvedopen} }
+@Rowa
+ A { " arrowwidth"}
+ B { 0.3f }
+ C { any @I length }
+@Rowa
+ A { " arrowlength"}
+ B { 0.5f }
+ C { any @I length }
+@Rowa
+ A { " linklabel"}
+ B { }
+ C { any object }
+@Rowa
+ A { " linklabelmargin"}
+ B { 0.2f }
+ C { any length from Section {@NumberOf objects} }
+@Rowa
+ A { " linklabelfont"}
+ B { -2p }
+ C { any value suitable for the @Code "@Font" symbol }
+@Rowa
+ A { " linklabelbreak"}
+ B { ragged nohyphen }
+ C { any value suitable for the @Code "@Break" symbol }
+@Rowa
+ A { " linklabelformat"}
+ B { "@Body" }
+ C { any object, usually containing @Code "@Body" }
+@Rowa
+ A { " linklabelpos"}
+ B { }
+ C { any @I point }
+@Rowa
+ A { " linklabelangle"}
+ B { horizontal }
+ C { {@Code horizontal}, {@Code aligned}, or {@Code perpendicular};
+{@Code parallel}, {@Code antiparallel}, or any @I angle }
+@Rowa
+ A { " linklabelprox"}
+ B { above }
+ C { {@Code above}, {@Code below}, {@Code left}, {@Code right},
+{@Code inside}, or {@Code outside}; {@Code CTR}, {@Code N}, {@Code S},
+{@Code E}, {@Code W}, {@Code NE}, {@Code NW}, {@Code SW}, or {@Code SE}
+}
+@Rowa
+ A { " linklabelctr"}
+ B { no }
+ C { @Code yes or @Code no }
+@Rowa
+ A { " linklabeladjust"}
+ B { 0 0 }
+ C { any @I point }
+@Rowa
+ A { " xlabelpos"}
+ B { LFROM }
+ C { any @I point }
+@Rowa
+ A { " ylabelpos"}
+ B { LMID }
+ C { any @I point }
+@Rowa
+ A { " ylabelctr"}
+ B { yes }
+ C { @Code yes or @Code no }
+@Rowa
+ A { " zlabelpos"}
+ B { LTO }
+ C { any @I point }
+@Rowa
+ A { " fromlabel"}
+ B { }
+ C { any object }
+@Rowa
+ A { " fromlabelmargin"}
+ B { 0f }
+ C { any length from Section {@NumberOf objects} }
+@Rowa
+ A { " fromlabelfont"}
+ B { }
+ C { Any value suitable for the @Code "@Font" symbol }
+@Rowa
+ A { " fromlabelbreak"}
+ B { ragged nohyphen }
+ C { Any value suitable for the @Code "@Break" symbol }
+@Rowa
+ A { " fromlabelformat"}
+ B { "@Body" }
+ C { any object, usually containing @Code "@Body" }
+@Rowa
+ A { " fromlabelpos"}
+ B { FROM }
+ C { any @I point }
+@Rowa
+ A { " fromlabelangle"}
+ B { antiparallel }
+ C { {@Code horizontal}, {@Code aligned}, or {@Code perpendicular};
+{@Code parallel}, {@Code antiparallel}, or any @I angle }
+@Rowa
+ A { " fromlabelprox"}
+ B { W }
+ C { {@Code above}, {@Code below}, {@Code left}, {@Code right},
+{@Code inside}, or {@Code outside}; {@Code CTR}, {@Code N}, {@Code S},
+{@Code E}, {@Code W}, {@Code NE}, {@Code NW}, {@Code SW}, or {@Code SE}
+}
+@Rowa
+ A { " fromlabelctr"}
+ B { no }
+ C { @Code yes or @Code no }
+@Rowa
+ A { " fromlabeladjust"}
+ B { 0 0 }
+ C { any @I point }
+@Rowa
+ A { " tolabel"}
+ B { }
+ C { any object }
+@Rowa
+ A { " tolabelmargin"}
+ B { 0f }
+ C { any length from Section {@NumberOf objects} }
+@Rowa
+ A { " tolabelfont"}
+ B { }
+ C { Any value suitable for the @Code "@Font" symbol }
+@Rowa
+ A { " tolabelbreak"}
+ B { ragged nohyphen }
+ C { Any value suitable for the @Code "@Break" symbol }
+@Rowa
+ A { " tolabelformat"}
+ B { "@Body" }
+ C { any object, usually containing @Code "@Body" }
+@Rowa
+ A { " tolabelpos"}
+ B { TO }
+ C { any @I point }
+@Rowa
+ A { " tolabelangle"}
+ B { parallel }
+ C { {@Code horizontal}, {@Code aligned}, or {@Code perpendicular};
+{@Code parallel}, {@Code antiparallel}, or any @I angle }
+@Rowa
+ A { " tolabelprox"}
+ B { W }
+ C { {@Code above}, {@Code below}, {@Code left}, {@Code right},
+{@Code inside}, or {@Code outside}; {@Code CTR}, {@Code N}, {@Code S},
+{@Code E}, {@Code W}, {@Code NE}, {@Code NW}, {@Code SW}, or {@Code SE}
+}
+@Rowa
+ A { " tolabelctr"}
+ B { no }
+ C { @Code yes or @Code no }
+@Rowa
+ A { " tolabeladjust"}
+ B { 0 0 }
+ C { any @I point }
+}
+@DP
+Here is the complete list of options to the @Code "@Tree" symbol:
+@DP @OneRow 1fx @Break @Tab
+ hmargin { 1s }
+ # vmargin { 0.6vx }
+ @Fmth { @Col @Code A ! @Col @Code " " ! @Col @Code B ! @Col @Code " " !
+ @Col 1.0c @Wide ! @Col C }
+ @Fmta { @Col @Code A ! @Col @Code "{" ! @Col @Code B ! @Col @Code "}" !
+ @Col 1.0c @Wide ! @Col C }
+{
+@Rowh
+ A { "@Tree" }
+@Rowa
+ A { " treehindent" }
+ B { ctr }
+ C { {@Code left}, {@Code ctr}, {@Code right}, or any length from
+Section {@NumberOf objects} }
+}
+@DP
+The @Code "@HTree" option has a similar @Code "treevindent" option,
+which may be {@Code "top"}, {@Code ctr}, {@Code foot}, or any length
+from Section {@NumberOf objects}.
+@PP
+The @Code "@Diag" symbol and to the {@Code "@DiagSetup"} setup
+file symbol have all of the options of {@Code "@Node"}, {@Code "@Link"},
+{@Code "@Tree"}, and {@Code "@HTree"}. They also have the following
+options:
+@DP
+1fx @Break @Tab
+ hmargin { 1s }
+ # vmargin { 0.6vx }
+ @Fmth { @Col @Code A ! @Col @Code " " ! @Col @Code B ! @Col @Code " " !
+ @Col 1.0c @Wide ! @Col C }
+ @Fmta { @Col @Code A ! @Col @Code "{" ! @Col @Code B ! @Col @Code "}" !
+ @Col 1.0c @Wide ! @Col C }
+{
+@Rowh
+ A { "@Diag" }
+@Rowa
+ A { " maxlabels" }
+ B { 200 }
+ C { any whole number }
+@Rowa
+ A { " save" }
+ B { no }
+ C { @Code no or @Code yes }
+@Rowa
+ A { " treehsep" }
+ B { 0.5f }
+ C { any length from Section {@NumberOf objects} }
+@Rowa
+ A { " treevsep" }
+ B { 0.5f }
+ C { any length from Section {@NumberOf objects} }
+}
+@DP
+The following lists define all the ways to specify numbers, lengths,
+angles, points, and booleans. Brief explanations appear to the right,
+with the symbols' precedences in parentheses.
+@DP
+1fx @Break @Tab
+ # vmargin { 0.6vx }
+ @Fmth { @Col { &@DisplayIndent A } ! @Col }
+ @Fmta { @Col { &@DisplayIndent &2s A } ! @Col B }
+{
+
+@Rowh A { @I number } vmargin { 0.2vx }
+@Rowh
+@Rowa
+ A { {@Sym minus}27.56 }
+ B { or any literal number }
+@Rowa
+ A { @Code sqrt @I number }
+ B { square root (99) }
+@Rowa
+ A { @Code abs @I number }
+ B { absolute value (99) }
+@Rowa
+ A { @Code ceiling @I number }
+ B { least integer greater than or equal to (99) }
+@Rowa
+ A { @Code floor @I number }
+ B { greatest integer less than or equal to (99) }
+@Rowa
+ A { @Code truncate @I number }
+ B { delete fractional part (99) }
+@Rowa
+ A { @Code round @I number }
+ B { round to nearest integer (99) }
+@Rowa
+ A { @Code sin @I angle }
+ B { sine of angle measured in degrees (99) }
+@Rowa
+ A { @Code cos @I angle }
+ B { cosine of angle measured in degrees (99) }
+@Rowa
+ A { @I number @Code atan @I number }
+ B { arc tangent of first over second (98) }
+@Rowa
+ A { @I number @Code exp @I number }
+ B { first number raised to second number (98) }
+@Rowa
+ A { @I number @Code log @I number }
+ B { logarithm of second number to base first (98) }
+@Rowa
+ A { @I number @Code rand @I number }
+ B { random real number in this range inclusive (98) }
+@Rowa
+ A { @I number @Code max @I number }
+ B { the larger of two numbers (98) }
+@Rowa
+ A { @I number @Code min @I number }
+ B { the smaller of two numbers (98) }
+@Rowa
+ A { @I number @Code "*" @I number }
+ B { the product of two numbers (97) }
+@Rowa
+ A { @I number @Code "/" @I number }
+ B { real-valued division (96, left associative) }
+@Rowa
+ A { @I length @Code "/" @I length }
+ B { the ratio of two lengths (96, left associative) }
+@Rowa
+ A { @I angle @Code "/" @I angle }
+ B { the ratio of two angles (96, left associative) }
+@Rowa
+ A { @I number @Code idiv @I number }
+ B { integer division of two numbers (96, left associative) }
+@Rowa
+ A { @I number @Code mod @I number }
+ B { integer remainder when first divided by second (96) }
+@Rowa
+ A { @I number @Code "+" @I number }
+ B { sum of two numbers (96, left associative) }
+@Rowa
+ A { @Code "+" @I number }
+ B { identity operation (96) }
+@Rowa
+ A { @I number @Sym minus @I number }
+ B { difference of two numbers (96, left associative) }
+@Rowa
+ A { @Sym minus @I number }
+ B { negation (96) }
+@Rowa
+ A { @Code sides }
+ B { ({@Code outline} only) value of the node's @Code sides option }
+
+@Rowh
+@Rowh
+@Rowh
+@Rowh
+@Rowh A { @I length } vmargin { 0.2vx }
+@Rowh
+@Rowa
+ A { 0 }
+ B { zero }
+@Rowa
+ A { @Code xsize }
+ B { ({@Code outline} only) distance to right boundary }
+@Rowa
+ A { @Code ysize }
+ B { ({@Code outline} only) distance to top boundary }
+@Rowa
+ A { @Code xmark }
+ B { ({@Code outline} only) distance to column mark }
+@Rowa
+ A { @Code ymark }
+ B { ({@Code outline} only) distance to row mark }
+@Rowa
+ A { @Code margin }
+ B { ({@Code outline} only) value of the node's @Code margin option }
+@Rowa
+ A { @Code shadow }
+ B { ({@Code outline} only) value of the node's @Code shadow option }
+@Rowa
+ A { @I number @Code i }
+ B { @I number inches (100) }
+@Rowa
+ A { @I number @Code c }
+ B { @I number centimetres (100) }
+@Rowa
+ A { @I number @Code p }
+ B { @I number points (100) }
+@Rowa
+ A { @I number @Code m }
+ B { @I number ems (100) }
+@Rowa
+ A { @I number @Code s }
+ B { @Code 1s is the current width of a space (100) }
+@Rowa
+ A { @I number @Code v }
+ B { @Code 1v is the current inter-line space (100) }
+@Rowa
+ A { @I number @Code f }
+ B { @Code 1f is the size of the current font (100) }
+@Rowa
+ A { @Code "xcoord" @I point }
+ B { the @I x coordinate of the point (99) }
+@Rowa
+ A { @Code "ycoord" @I point }
+ B { the @I y coordinate of the point (99) }
+@Rowa
+ A { @Code abs @I length }
+ B { absolute value (99) }
+@Rowa
+ A { @I length @Code rand @I length }
+ B { random real length in this range inclusive (98) }
+@Rowa
+ A { @I length @Code max @I length }
+ B { the larger of two lengths (98) }
+@Rowa
+ A { @I length @Code min @I length }
+ B { the smaller of two lengths (98) }
+@Rowa
+ A { @I point @Code "distance" @I point }
+ B { (non-negative) distance between two points (98) }
+@Rowa
+ A { @I length @Code "*" @I number }
+ B { length multiplied by number (97) }
+@Rowa
+ A { @I number @Code "*" @I length }
+ B { length multiplied by number (97) }
+@Rowa
+ A { @I length @Code "/" @I number }
+ B { length divided by number (96, left associative) }
+@Rowa
+ A { @I length @Code "+" @I length }
+ B { sum of two lengths (96, left associative) }
+@Rowa
+ A { @Code "+" @I length }
+ B { identity operation (96) }
+@Rowa
+ A { @I length @Sym minus @I length }
+ B { difference of two lengths (96, left associative) }
+@Rowa
+ A { @Sym minus @I length }
+ B { negation (96) }
+
+@Rowh
+@Rowh
+@Rowh
+@Rowh
+@Rowh A { @I angle } vmargin { 0.2vx }
+@Rowh
+@Rowa
+ A { @I number @Code d }
+ B { @I number degrees (100) }
+@Rowa
+ A { @I number }
+ B { @I number degrees (@Code d is optional) (100) }
+@Rowa
+ A { @Code parallel }
+ B { ({@Code labelangle} options only) angle parallel to curve at label point }
+@Rowa
+ A { @Code antiparallel }
+ B { ({@Code labelangle} options only) angle antiparallel to curve at label point }
+@Rowa
+ A { @Code perpendicular }
+ B { ({@Code labelangle} options only) angle perpendicular to curve at label point }
+@Rowa
+ A { @Code antiperpendicular }
+ B { ({@Code labelangle} options only) angle antiperpendicular to curve at label point }
+@Rowa
+ A { {@I label}{@Code "??ANGLE"} }
+ B { angle parallel to curve at {@I label} if known, else @Code "0d" (99) }
+@Rowa
+ A { @Code anglefix @I angle }
+ B { @I angle normalized to between @Code 0d inclusive and @Code 360d exclusive (99) }
+@Rowa
+ A { @Code abs @I angle }
+ B { absolute value (99) }
+@Rowa
+ A { @I length @Code atan @I length }
+ B { arc tangent of first over second (98) }
+@Rowa
+ A { @I point @Code "angleto" @I point }
+ B { angle from first point to second (98) }
+@Rowa
+ A { @I angle @Code rand @I angle }
+ B { random angle in this range inclusive (98) }
+@Rowa
+ A { @I angle @Code max @I angle }
+ B { the larger of two angles (98) }
+@Rowa
+ A { @I angle @Code min @I angle }
+ B { the smaller of two angles (98) }
+@Rowa
+ A { @I angle @Code "*" @I number }
+ B { angle multiplied by number (97) }
+@Rowa
+ A { @I number @Code "*" @I angle }
+ B { angle multiplied by number (97) }
+@Rowa
+ A { @I angle @Code "/" @I number }
+ B { division of angle by number (96, left associative) }
+@Rowa
+ A { @I angle @Code "+" @I angle }
+ B { sum of two angles (96, left associative) }
+@Rowa
+ A { @Code "+" @I angle }
+ B { identity operation (96) }
+@Rowa
+ A { @I angle @Sym minus @I angle }
+ B { difference of two angles (96, left associative) }
+@Rowa
+ A { @Sym minus @I angle }
+ B { negation (96) }
+@Rowa
+ A { @Code angle }
+ B { ({@Code outline} only) value of the node's @Code angle option }
+
+
+@Rowh
+@Rowh
+@Rowh
+@Rowh
+@Rowh A { @I point } vmargin { 0.2vx }
+@Rowh
+@Rowa
+ A { @I label }
+ B { a previously defined label }
+@Rowa
+ A { {@I any}{@Code "??"}{@I label} }
+ B { {@I any}{@Code "@"}{@I label} if sensible, else {@I any} (99) }
+@Rowa
+ A { @Code "prev" }
+ B { the previous point in a shape }
+@Rowa
+ A { @I length @Code "atangle" @I angle }
+ B { point at distance and angle from origin (89) }
+@Rowa
+ A { @I "point/tag" @Code "boundaryatangle" @I angle }
+ B { @I {point}, or point on boundary of @I tag at @I angle (89) }
+@Rowa
+ A { @I point @Code "**" @I number }
+ B { multiplication of point by number (88) }
+@Rowa
+ A { @I point @Code "++" @I point }
+ B { vector sum of two points (87) }
+@Rowa
+ A { @I point {@Sym minus}{@Sym minus} @I point }
+ B { vector difference of two points (87) }
+@Rowa
+ A { @I {number, number} }
+ B { @I x and @I y coordinates with respect to base (70) }
+@Rowa
+ A { @I {length length} }
+ B { @I x and @I y distance from origin (5) }
+@Rowa
+ A { @Code from }
+ B { ({@Code path} only) the value of the link's @Code from option }
+@Rowa
+ A { @Code to }
+ B { ({@Code path} only) the value of the link's @Code to option }
+
+@Rowh
+@Rowh
+@Rowh
+@Rowh
+@Rowh A { @I boolean } vmargin { 0.2vx }
+@Rowh
+@Rowa
+ A { @I number @Code "=" @I number }
+ B { @Eq { non = }; also between lengths (79) }
+@Rowa
+ A { @I number @Code "!=" @I number }
+ B { @Eq { non != }; also between lengths (79) }
+@Rowa
+ A { @I number @Code "==" @I number }
+ B { @Eq { non = } between angles (79) }
+@Rowa
+ A { @I number @Code "!==" @I number }
+ B { @Eq { non != } between angles (79) }
+@Rowa
+ A { @I number @Code "<=" @I number }
+ B { @Eq { non <= }; also between lengths (79) }
+@Rowa
+ A { @I number @Code "<" @I number }
+ B { @Eq { non < }; also between lengths (79) }
+@Rowa
+ A { @I number @Code ">=" @I number }
+ B { @Eq { non >= }; also between lengths (79) }
+@Rowa
+ A { @I number @Code ">" @I number }
+ B { @Eq { non > }; also between lengths (79) }
+@Rowa
+ A { @Code "not" @I boolean }
+ B { Logical not (78) }
+@Rowa
+ A { @I boolean @Code "and" @I boolean }
+ B { Logical and (77) }
+@Rowa
+ A { @I boolean @Code "or" @I boolean }
+ B { Logical or (76) }
+@Rowa
+ A { @I boolean @Code "xor" @I boolean }
+ B { Logical exclusive or (76) }
+
+}
+@DP
+A length is represented in PostScript by a single number on the operand
+stack; so is an angle. Therefore all number operations can be applied
+to lengths and angles as well, but the results will not always be
+useful. For example, rounding a length to the nearest integer is
+not a useful thing to do because the result depends on the basic unit
+(what does 1 equal as a length?) which is implementation-dependent and
+genuinely subject to change. Rounding the @I ratio of two lengths does
+make sense. The above is an attempt to list only the useful operations;
+but if you really need the logarithm of an angle, you can have it.
+@PP
+Angles are a little more amenable to this kind of thing because they are
+always measured in degrees. However, angles suffer from the problem that
+{@Code 0d} is really the same angle as {@Code 360d}. For this reason,
+separate equality and inequality operators for angles are provided which
+ignore multiples of {@Code 360d}, and less than and similar relations
+are not defined for angles, because they inherently are not well
+defined. See also the @Code anglefix symbol above.
+@PP
+A point is represented by two lengths (which are numbers) on the
+stack. Those familiar with PostScript and willing to sacrifice portability
+and increase their risk of error can therefore write, for example,
+@OneCol { @I point @Code "exch" } to obtain the reflection of a point about
+the main diagonal, and so on.
+@PP
+The following may have a result of any type, depending on
+their options. The options and result may be a
+sequence of things as required in shapes, including @Code "[]" and
+so forth.
+@IndentedList
+@LI @OneRow lines @Break {
+@Code if
+ @Code "cond {" @I boolean @Code "}"
+ @Code "then {" @I anything @Code "}"
+ @Code "else {" @I anything @Code "}"
+}
+@LI @OneRow lines @Break {
+@I angle @Code quadcase
+ @Code "0 {" @I anything @Code "}"
+ @Code "0-90 {" @I anything @Code "}"
+ @Code "90 {" @I anything @Code "}"
+ @Code "90-180 {" @I anything @Code "}"
+ @Code "180 {" @I anything @Code "}"
+ @Code "180-270 {" @I anything @Code "}"
+ @Code "270 {" @I anything @Code "}"
+ @Code "270-360 {" @I anything @Code "}"
+}
+@LI @OneRow lines @Break {
+@I number @Code signcase
+ @Code "neg {" @I anything @Code "}"
+ @Code "zero {" @I anything @Code "}"
+ @Code "pos {" @I anything @Code "}"
+}
+@LI @OneRow lines @Break {
+@Code "xloop from {" @I number "} to {" @I number "} by {" @I number "} do {"
+ @I anything
+@Code "}"
+}
+@LI @OneRow lines @Break {
+@Code "yloop from {" @I number "} to {" @I number "} by {" @I number "} do {"
+ @I anything
+@Code "}"
+}
+@LI @OneRow lines @Break {
+@Code "zloop from {" @I number "} to {" @I number "} by {" @I number "} do {"
+ @I anything
+@Code "}"
+}
+@EndList
+The @Code "if" symbol returns @Code "then" or @Code "else" depending on
+the value of {@Code "cond"}, and @Code "signcase" returns {@Code "neg"},
+{@Code zero}, or {@Code pos} depending on whether @I number (which
+may also be an angle or a length) is negative, zero, or positive. The
+@Code "quadcase" symbol decides whether the given angle points in
+one of the four horizontal or vertical directions, or into the quadrants
+between them, and returns the appropriate option. Don't be misled by
+the unorthodox option names; it is not possible to give your own
+ranges, only these ones.
+@PP
+The loops return a sequence of
+repetitions of {@I anything}; any occurrences of {@Code x} in
+{@Code xloop} will be replaced by the current value of the loop counter,
+and similarly for the other loops.
+@PP
+Symbols not covered in this summary are the retagging symbol @Code "::"
+(Section {@NumberOf dia_tags}); the symbols available within the
+{@Code "@Tree"} symbol (Section {@NumberOf dia_posi}); and {@Code ":<"},
+{@Code ":="}, {@Code "@ShowPoints"}, {@Code "@ShowTags"}, and
+{@Code "@ShowDirections"} from Section {@NumberOf dia_defi}.
+@End @Section