Update docs.

README.md

@@ -0,0 +1,63 @@
+# GIOWrap
+
+An experimental wrapper package for the Gio immediate mode GUI, designed to reduce
+boilerplate.
+
+The basic concept is to define a `Context` type that contains the Gio variables
+required for layout and drawing. `Context` contains a pointer to `app.Window` and
+`ui.Ops` so that, once layout is complete, you can call `Context.Draw()` to draw
+your objects in your window.
+
+The following types and functions are defined in order to transform a `Context`
+variable during layout:
+
+```go
+type Layout func(Context) Context
+
+type Widget interface {
+	Layout(Context) Context
+}
+
+func LayoutWithContext(ctx Context, ws ...Widget) Context {
+	for _, w := range ws {
+		ctx = w.Layout(ctx)
+	}
+	return ctx
+}
+
+type WidgetCombinator func(...Widget) Widget
+
+type Enclosure interface {
+	Begin(Context) Context
+	End(Context) Context
+}
+
+func Enclose(e Enclosure, w ...Widget) Widget { ... }
+```
+
+The `Context` struct also contains a `map[string]interface{}` allowing arbitrary
+data to be maintained. This can be used, for example, to define themes, and control
+the operation of a `WidgetCombinator` during operation. For example>
+
+```go
+type fWidget struct { l Layout }
+func NewfWidget(l layout) fWidget { return fWidget{ l: l } }
+
+func (f Flex) Flexible(v float32) Widget {
+	return NewfWidget(func(ctx Context) Context {
+		ctx.extra["Flexible"] = v
+		return ctx
+	})
+}
+
+...
+	ctx = giowrap.LayoutWithContext(ctx,
+		myFlex(
+			w1,
+			giowrap.Flexible(0.5),
+			w2,
+			giowrap.Flexible(1),
+			w3,
+		))
+...
+```

cmd/hello/main.go

@@ -57,9 +57,9 @@ func main() {
 						OuterInset(
 						    f(
 							e1,
-							f.Flexible(5),
+							giowrap.Flexible(5),
 							InnerInset(e2),
-							f.Flexible(10),
+							giowrap.Flexible(10),
 							btn,
 						)))
 					ctx.Draw()

main.go

@@ -51,11 +51,9 @@ func (ctx Context) Draw() {
 
 type Layout func(Context) Context
 
-type LayoutCombinator func(...Layout) Layout
+func LayoutWithContext(ctx Context, ws ...Widget) Context {
-
+	for _, w := range ws {
-func LayoutWithContext(ctx Context, ls ...Widget) Context {
+		ctx = w.Layout(ctx)
-	for _, l := range ls {
-		ctx = l.Layout(ctx)
 	}
 	return ctx
 }
@@ -151,7 +149,7 @@ type FlexChild struct {
 
 type Flex WidgetCombinator
 
-func (f Flex) Flexible(v float32) Widget {
+func Flexible(v float32) Widget {
 	return NewfWidget(func(ctx Context) Context {
 		ctx.extra["Flexible"] = v
 		return ctx