added cairo_anim.nim example

README.adoc

@@ -642,5 +642,67 @@ code you may catch such exceptions with Nim's `try:` blocks. (You may also modif
 an illegal CSS statement -- if the statement is seriously wrong, then you should get an exception from
 loadFromData().
 
+== Drawing with Cairo graphics library
+
+The next example shows how we can use the cairo graphics library for drawing on a DrawingArea widget,
+and at the same time uses glib timeoutAdd() function to create a timer which periodically calls the
+drawing function to create some animations. The code is based on a recent post to the cairo mailing list
+and shows a sine wave which is continuously moving to the left.
+
+NOTE: The gobject-introspection generated cairo module was only a minimal stub, because cairo
+library does not really support introspection. Now we are using a cairo module which is generated 
+directly from the cairo C header files with the tool c2nim and then modified to support an high level
+API. That modification is still work in progress, so not all cairo functionality is available already. 
+
+[[cairo_anim.nim]]
+[source,nim]
+.cairo_anim.nim
+----
+# nim c cairo_anim.nim
+# https://lists.cairographics.org/archives/cairo/2016-October/027791.html
+# Nim version of that plain cairo animation example
+
+import gintro/[gtk, glib, gobject, gio, cairo]
+import math
+
+const
+  NumPoints = 1000
+  Period = 100.0
+
+proc invalidateCb(w: Widget): bool =
+  queueDraw(w)
+  return SOURCE_CONTINUE
+
+proc sineToPoint(x, width, height: int): float =
+  math.sin(x.float * math.TAU / Period) * height.float * 0.5 + height.float * 0.5
+
+proc drawingAreaDrawCb(widget: DrawingArea; context: Context): bool =
+  var redrawNumber {.global.} : int
+  let width = getAllocatedWidth(widget)
+  let height = getAllocatedHeight(widget)
+  for i in 1 .. < NumPoints:
+    context.lineTo(i.float , sineToPoint(i + redrawNumber, width, height))
+  context.stroke
+  inc(redrawNumber)
+  return true # TRUE to stop other handlers from being invoked for the event. FALSE to propagate the event further.
+
+proc activate(app: Application) =
+  let window = newApplicationWindow(app)
+  window.title = "Drawing example"
+  window.defaultSize = (400, 400)
+  let drawingArea = newDrawingArea()
+  window.add(drawingArea)
+  showAll(window)
+  discard timeoutAdd(1000 div 60, invalidateCb, drawingArea)
+  connect(drawingArea, "draw", drawingAreaDrawCb)
+
+proc main =
+  let app = newApplication("org.gtk.example")
+  connect(app, "activate", activate)
+  discard run(app)
+
+main()
+----
+
 NOTE: Related work: https://github.com/jdmansour/nim-smartgi
 

examples/cairo_anim.nim

@@ -0,0 +1,44 @@
+# https://lists.cairographics.org/archives/cairo/2016-October/027791.html
+# Nim version of that plain cairo animation example
+
+import gintro/[gtk, glib, gobject, gio, cairo]
+import math
+
+const
+  NumPoints = 1000
+  Period = 100.0
+
+proc invalidateCb(w: Widget): bool =
+  queueDraw(w)
+  return SOURCE_CONTINUE
+
+proc sineToPoint(x, width, height: int): float =
+  math.sin(x.float * math.TAU / Period) * height.float * 0.5 + height.float * 0.5
+
+proc drawingAreaDrawCb(widget: DrawingArea; context: Context): bool =
+  var redrawNumber {.global.} : int
+  let width = getAllocatedWidth(widget)
+  let height = getAllocatedHeight(widget)
+  for i in 1 .. < NumPoints:
+    context.lineTo(i.float , sineToPoint(i + redrawNumber, width, height))
+  context.stroke
+  inc(redrawNumber)
+  return true # TRUE to stop other handlers from being invoked for the event. FALSE to propagate the event further.
+
+proc activate(app: Application) =
+  let window = newApplicationWindow(app)
+  window.title = "Drawing example"
+  window.defaultSize = (400, 400)
+  let drawingArea = newDrawingArea()
+  window.add(drawingArea)
+  showAll(window)
+  discard timeoutAdd(1000 div 60, invalidateCb, drawingArea)
+  connect(drawingArea, "draw", drawingAreaDrawCb)
+
+proc main =
+  let app = newApplication("org.gtk.example")
+  connect(app, "activate", activate)
+  discard run(app)
+
+main()
+

gintro/gimpl.nim

@@ -26,14 +26,12 @@ proc findSignal(name, obj: NimNode): string =
         n = getType(n)[1]
 
 var ProcID: int
-
+#
-macro mconnect(widget: gobject.Object; signal: string; p: untyped; arg: typed; ignoreArg: bool): typed =
+macro mconnect(widget: gobject.Object; signal: string; p: untyped; arg: typed; ignoreArg: bool): untyped =
   inc(ProcID)
   let wt = getType(widget)
-  #echo "@@@", $(getTypeInst(widget).toStrLit)
   let at = getTypeInst(arg)
   let wts = ($(wt[1].toStrLit)).replace(":ObjectType")
-  #echo wts
   let ats = $at.toStrLit
   let signalName = ($signal).replace("-", "_") # maybe we should just use plain proc names
   let procNameCdecl = "connect_for_signal_cdecl_" & signalName & $ProcID
@@ -53,14 +51,12 @@ proc $1$2 {.cdecl.} =
     r1s.add(")\n")
   else:
     (sn, wid, num, ahl, all) = sci.split("|")
-    #echo ahl, all
     var resl: string
     if ahl.contains("): "):
       resl = all.rsplit("): ", 1)[1]
     var resu = "  $3(cast[$4](h)"
     if all.find(";") > 0:
       var largs = all.split("; ")
-      #if largs.len > 0:
       largs.delete(0)
       largs[^1] = largs[^1].split(")")[0] 
       var names, types: array[10, string]
@@ -76,7 +72,6 @@ proc $1$2 {.cdecl.} =
           if h.len > 0:
             a1 = h & "(" & a1 & ")"
           plainArgs.add(a1)
-      #var resu = "  $3(cast[$4](h)"
       for i in 0 .. 9:
         if names[i].isNil: break
         resu.add(", " & names[i] & "1")
@@ -93,27 +88,23 @@ proc $1$2 {.cdecl.} =
     r1s.add(resu & "\n")
     all = all.replace(")", "; data: pointer)")
   r1s = r1s % [$procNameCdecl, all, $p, wts, ats]
-  #echo r1s
   result = parseStmt(r1s)
   if not ignoreArg.boolVal:
     ahl = ahl.replace(")", "; arg: " & ats & ")")
-  #echo ahl
   if ahl.find(";") > 0:
     ahl = "(self: " & wts & ";" & ahl.split(";", 1)[1]
   else:
     ahl = "(self: " & wts & ")" & ahl.split(")", 1)[1]
-    #ahl = "(self: " & wts & ")"
-
   let r2s =
     if ignoreArg.boolVal:
       """
-proc $1(self: $2;  p: proc $3) =
+proc $1(self: $2;  p: proc $3): culong {.discardable.} =
   sc$4(self, $5, nil)
 $1($6, $7)
 """ % [$procName, wts, ahl, signalName,  $procNameCdecl, $(widget.toStrLit), $p]
     else:
       """
-proc $1(self: $2;  p: proc $3; a: $4) =
+proc $1(self: $2;  p: proc $3; a: $4): culong {.discardable.} =
   when a is RootRef:
     GC_ref(a)
     sc$5(self, $6, cast[pointer](a))
@@ -125,13 +116,71 @@ proc $1(self: $2;  p: proc $3; a: $4) =
     sc$5(self, $6, cast[pointer](ar[]))
 $1($7, $8, $9)
 """ % [$procName, wts,  ahl, ats, signalName,  $procNameCdecl, $(widget.toStrLit), $p, $(arg.toStrLit)]
-  #echo r2s
   result.add(parseStmt(r2s))
 
-template connect*(widget: gobject.Object; signal: string; p: untyped; arg: typed): typed =
+template connect*(widget: gobject.Object; signal: string; p: untyped; arg: typed): untyped =
   mconnect(widget, signal, p, arg, false)
 
-template connect*(widget: gobject.Object; signal: string; p: untyped): typed =
+template connect*(widget: gobject.Object; signal: string; p: untyped): untyped =
   mconnect(widget, signal, p, "", true)
 
+var TimeoutID: int
+#
+macro timeoutAdd*(interval: Natural; p: untyped; arg: typed): untyped =
+  inc(TimeoutID)
+  let ats = $getTypeInst(arg).toStrLit
+  let procName = "timeoutfunc_" & $TimeoutID
+  let procNameCdecl = "timeoutfunc_cdecl_" & $TimeoutID
+  var r1s = """
+proc $1(p: pointer): gboolean {.cdecl.} =
+  let a = cast[$3](p)
+  result = $2(a).gboolean
+  #when (a is ref object) or (a is seq):
+  GC_unref(a)
+""" % [$procNameCdecl, $p, ats]
+ 
+  let r2s ="""
+proc $1(a: $2): culong {.discardable.} =
+  when (a is ref object) or (a is seq):
+    GC_ref(a)
+    return g_timeout_add_full(PRIORITY_DEFAULT, $3, $4, cast[pointer](a), nil)
+  else:
+    var ar: ref $2
+    new(ar)
+    deepCopy(ar[], a)
+    GC_ref(ar)
+    return g_timeout_add_full(PRIORITY_DEFAULT, $3, $4, cast[pointer](ar), nil)
+$1($5)
+""" % [$procName, ats, $interval.toStrLit, $procNameCdecl, $arg]
+  result = parseStmt(r1s & r2s)
+
+var IdleID: int
+#
+macro idleAdd*(p: untyped; arg: typed): untyped =
+  inc(IdleID)
+  let ats = $getTypeInst(arg).toStrLit
+  let procName = "idlefunc_" & $IdleID
+  let procNameCdecl = "idlefunc_cdecl_" & $IdleID
+  var r1s = """
+proc $1(p: pointer): gboolean {.cdecl.} =
+  let a = cast[$3](p)
+  result = $2(a).gboolean
+  #when (a is ref object) or (a is seq):
+  GC_unref(a)
+""" % [$procNameCdecl, $p, ats]
+ 
+  let r2s ="""
+proc $1(a: $2): culong {.discardable.} =
+  when (a is ref object) or (a is seq):
+    GC_ref(a)
+    return g_idle_add_full(PRIORITY_DEFAULT_IDLE, $3, cast[pointer](a), nil)
+  else:
+    var ar: ref $2
+    new(ar)
+    deepCopy(ar[], a)
+    GC_ref(ar)
+    return g_idle_add_full(PRIORITY_DEFAULT_IDLE, $3, cast[pointer](ar[]), nil)
+$1($4)
+""" % [$procName, ats, $procNameCdecl, $arg]
+  result = parseStmt(r1s & r2s)
 

tests/gen.nim

@@ -1,5 +1,5 @@
 # High level gobject-introspection based GTK3 bindings for the Nim programming language
-# v 0.2 2017-AUG-29
+# v 0.2 2017-SEP-08
 # (c) S. Salewski 2017
 
 # https://wiki.gnome.org/Projects/GObjectIntrospection
@@ -108,7 +108,6 @@ var fixedProcNames = newTable[string, string]()
 var mangledNames = newTable[string, string]()
 var gdkKeys = newTable[string, seq[string]]()
 var allSyms: HashSet[string]
-#var scfilter: HashSet[string]
 var provInt = newTable[string, seq[string]]()
 var interfaceProvider = newTable[string, seq[string]]()
 var priList: seq[string]
@@ -116,8 +115,8 @@ var knownSyms: HashSet[string]
 var suppressType = false
 var suppressRaise = false
 var droppedSyms = initSet[string]()
-var  callerAlloc = initSet[string]()
+var callerAlloc = initSet[string]()
-var  callerAllocCollector = initSet[string]()
+var callerAllocCollector = initSet[string]()
 var privStr = initSet[string]()
 var processedFunctions = initSet[string]()
 var delayedMethods: seq[(GIBaseInfo, GIFunctionInfo)]
@@ -142,6 +141,12 @@ mangledNames.add("2buttonPress", "twoButtonPress")
 mangledNames.add("3buttonPress", "threeButtonPress")
 mangledNames.add("result", "resu")
 
+proc gBaseInfoGetName(info: GIBaseInfo): string =
+  result = $(gir.gBaseInfoGetName(info))
+  let h = $(gir.gBaseInfoGetNamespace(info))
+  if h == "Gio" and result == "Application":
+    result = "GApplication"
+
 proc mangleName(s: cstring): string =
   result = mysnakeToCamel(s)
   if mangledNames.contains(result):
@@ -348,7 +353,10 @@ proc genP(info: GICallableInfo; genProxy = false; binfo: GIBaseInfo = nil): (str
     else:
       arglist = "(cast[ptr " & manglename(gBaseInfoGetName(binfo)) & "00](" & "self.impl)"
       if genProxy:
-        resul = "(self: " & manglename(gBaseInfoGetName(binfo))
+        var h = manglename(gBaseInfoGetName(binfo))
+        if (sym.startsWith("gdk_events_get_") or sym.startsWith("gdk_event_get_")) and h == "Event":
+          h = "SomeEvent"
+        resul = "(self: " & h
       else:
         resul = "(self: ptr " & manglename(gBaseInfoGetName(binfo)) & "00"
     if m >= 0:
@@ -399,6 +407,10 @@ proc genP(info: GICallableInfo; genProxy = false; binfo: GIBaseInfo = nil): (str
       (h1, h2, h3) = defaultParameters[sym].split
       if name == h1 and str == h2:
         str.add(" = " & h3)
+
+    if (sym.startsWith("gdk_events_get_") or sym.startsWith("gdk_event_get_")) and str == "Event":
+      str = "SomeEvent"
+
     resul.add(name & ": " & str)
     if j < m:
       resul.add("; ")
@@ -658,6 +670,11 @@ proc writeUnion(info: GIUnionInfo) =
     output.writeLine("    ", name, ": ", genRec(t))
   output.writeLine("  ", mangleName(gBaseInfoGetName(info))  & EM & " = ref object")
   output.writeLine("    impl*: ptr " & mangleName(gBaseInfoGetName(info)) & "00")
+
+  if mangleName(gBaseInfoGetName(info)) == "Event" and moduleNamespace == "gdk":
+    output.writeLine("type")
+    output.writeLine("  SomeEvent* = Event | EventButton | EventMotion | EventTouch | EventScroll | EventCrossing | EventTouchpadSwipe | EventTouchpadPinch")
+
   let nMethods = gUnionInfoGetNMethods(info)
   for j in 0 .. <nMethods:
     let mInfo =  gUnionInfoGetMethod(info, j)
@@ -887,10 +904,10 @@ proc writeObj(info: GIObjectInfo) =
     var xxx = mangleName(gBaseInfoGetName(info))
     output.write("proc " & mangleName("sc_" & $gBaseInfoGetName(signalInfo)) & EM & "(self: " & xxx & "; ")
     if gCallableInfoGetNArgs(signalInfo) > 0 or gTypeInfoGetTag(zzzu) != GITypeTag.VOID:
-      output.writeLine(" p: proc (self: ptr " & xxx & "00; " & h & " {.cdecl.}, xdata: pointer = nil) =")
+      output.writeLine(" p: proc (self: ptr " & xxx & "00; " & h & " {.cdecl.}, xdata: pointer = nil): culong =")
     else:
-      output.writeLine(" p: proc (self: ptr gobject.Object00; " & h & " {.cdecl.}, xdata: pointer = nil) =")
+      output.writeLine(" p: proc (self: ptr gobject.Object00; " & h & " {.cdecl.}, xdata: pointer = nil): culong =")
-    output.write("  discard g_signal_connect_data(self.impl, \"")
+    output.write("  g_signal_connect_data(self.impl, \"")
     output.write($gBaseInfoGetName(signalInfo))
     output.writeLine("\", cast[GCallback](p), xdata, nil, cast[ConnectFlags](0))")
   let nMethods = gObjectInfoGetNMethods(info)
@@ -1017,8 +1034,8 @@ proc fixednewCursorFromName*(display: Display; name: string): Cursor =
 
 const GIO_EPI = """
 
-proc run*(self: Application): int =
+proc run*(self: GApplication): int =
-  int(g_application_run(cast[ptr Application00](self.impl), 0, nil))
+  int(g_application_run(cast[ptr GApplication00](self.impl), 0, nil))
 
 """