Moved Shadow and added Background control.

ui/visual.go

@@ -1,9 +1,27 @@
 package ui
 
-import "opslag.de/schobers/geom"
+import (
+	"image/color"
 
-type shadow struct {
+	"opslag.de/schobers/geom"
+)
+
+func Background(content Control, c color.Color) Control {
+	return &background{Proxy: Proxy{Content: content}, Background: c}
+}
+
+type background struct {
 	Proxy
+
+	Background color.Color
+}
+
+func (b *background) Render(ctx Context) {
+	bounds := b.Proxy.Bounds()
+	if b.Background != nil {
+		ctx.Renderer().FillRectangle(bounds, b.Background)
+	}
+	b.Proxy.Render(ctx)
 }
 
 func Shadow(content Control) *shadow {
@@ -12,6 +30,10 @@ func Shadow(content Control) *shadow {
 	return s
 }
 
+type shadow struct {
+	Proxy
+}
+
 func (s *shadow) Render(ctx Context) {
 	s.Proxy.Render(ctx)
 	b := s.Bounds()