Add feedback components 106-130; inert scope, focus return, two-step deploy

feedback/pulse.go

@@ -0,0 +1,31 @@
+package feedback
+
+import (
+	"github.com/egoist/mygo/ui"
+
+	"git.zacharyzhang.com/ZacharyZhang-NY/8bitMyGoUI/pixel"
+)
+
+type PulseOptions struct {
+	// Slot colors the ring; zero means Accent.
+	Slot pixel.Slot
+}
+
+// Pulse rings its child with a ring growing in steps.
+func Pulse(c *ui.Context, o PulseOptions, content func()) *ui.Element {
+	k := pixel.K(c)
+	slot := o.Slot
+	if slot == 0 {
+		slot = pixel.Accent
+	}
+	return ui.Box(c).AlignSelf(ui.Start).Padding(k.D(6)).DrawOver(func(p *ui.Painter, r ui.Rect) {
+		g := k.Canvas(p, r)
+		f := g.Step(6) % 6
+		x, level := 5-f, 16-f*3
+		w, h := g.W-2*x, g.H-2*x
+		g.Veil(x, x, w, 1, slot, level)
+		g.Veil(x, x+h-1, w, 1, slot, level)
+		g.Veil(x, x, 1, h, slot, level)
+		g.Veil(x+w-1, x, 1, h, slot, level)
+	}).Children(content)
+}