Merge faaaf0c into 652e732

packages/math/init.lua

@@ -16,6 +16,7 @@ function package:_init ()
       return value * SILE.settings:get("math.font.size") / 18
     end
   })
+  self:loadPackage("counters")
 end
 
 function package.declareSettings (_)
@@ -67,16 +68,28 @@ function package:registerCommands ()
     xpcall(function()
       mbox = self:ConvertMathML(content, mbox)
     end, function(err) print(err); print(debug.traceback()) end)
-    self:handleMath(mbox, mode)
+    self:handleMath(mbox, mode, nil)
   end)
 
   self:registerCommand("math", function (options, content)
     local mode = (options and options.mode) and options.mode or "text"
     local mbox
+    local counter = (options and options.numbered) and "equation"
+    counter = (options and options.counter) and options.counter or counter
     xpcall(function()
       mbox = self:ConvertMathML(self:compileToMathML({}, self:convertTexlike(content)))
     end, function(err) print(err); print(debug.traceback()) end)
-    self:handleMath(mbox, mode)
+    self:handleMath(mbox, mode, counter)
+  end)
+
+  self:registerCommand("math-counterstyle", function (options, _)
+    SILE.typesetter:typeset("(")
+    SILE.call("show-counter", { id=options.id })
+    SILE.typesetter:typeset(")")
+  end)
+
+  self:registerCommand("equation", function (_, content)
+    SILE.call("math", {mode="display", counter="equation"}, content)
   end)
 
 end
@@ -344,6 +357,18 @@ Finally, here is a little secret. This notation:
 
 \noindent In other words, the notation using \code{&} and \code{\\\\} is only a syntactic sugar for a two-dimensional array constructed with braces.
 
+\paragraph{Equations numbering}
+Equations can be numbered in display mode adding the options \code{numbering} and \code{counter}.
+When \code{numbering=true}, the equations are numbered using a default "equation" counter.
+A different counter may be set by using the option \code{counter=id}, and this setting will also enable numbering. 
+The default numbering format is '(xx)', but this style may be overriden by defining a custom math-counterstyle function, e.g.
+
+\begin[type=autodoc:codeblock]{raw}
+\define[command=math-counterstyle]{(\show-counter[id="equation"])}
+\end{raw}
+
+There is also a \code{\\equation{...}}, that is an alias to \code{\\math[mode=display,counter=equation]{...}}
+
 \paragraph{Missing features}
 This package still lacks support for some mathematical constructs, but hopefully we’ll get there.
 Among unsupported constructs are: decorating symbols with so-called accents, such as arrows or hats, “over” or “under” braces, and line breaking inside a formula.

packages/math/typesetter.lua

@@ -126,7 +126,7 @@ function ConvertMathML (_, content)
   end
 end
 
-local function handleMath (_, mbox, mode)
+local function handleMath (_, mbox, mode, counter)
   if mode == 'display' then
     mbox.mode = b.mathMode.display
   elseif mode == 'text' then
@@ -144,9 +144,15 @@ local function handleMath (_, mbox, mode)
   if mode == "display" then
     SILE.typesetter:endline()
     SILE.typesetter:pushExplicitVglue(SILE.settings:get("math.displayskip"))
-    SILE.call("center", {}, function()
-      SILE.typesetter:pushHorizontal(mbox)
-    end)
+    SILE.typesetter:pushGlue(SILE.nodefactory.hfillglue())
+    SILE.typesetter:pushHorizontal(mbox)
+    SILE.typesetter:pushGlue(SILE.nodefactory.hfillglue())
+    if counter then
+      SILE.call("increment-counter", { id=counter } )
+      SILE.call("math-counterstyle", { id=counter } )
+    else
+      SILE.call("hbox")
+    end
     SILE.typesetter:endline()
     SILE.typesetter:pushExplicitVglue(SILE.settings:get("math.displayskip"))
   else