Add display components 041-065; move Icon into display; QR via rsc.io/qr

display/bubble.go

@@ -0,0 +1,73 @@
+package display
+
+import (
+	"fmt"
+
+	"github.com/egoist/mygo/ui"
+
+	"git.zacharyzhang.com/ZacharyZhang-NY/8bitMyGoUI/pixel"
+)
+
+type Side uint8
+
+const (
+	Bottom Side = iota
+	Top
+	Left
+	Right
+)
+
+type BubbleOptions struct {
+	// Tail is the side the tail leaves from.
+	Tail Side
+	// At offsets the tail along its side; zero means 8.
+	At int
+}
+
+const tailLen = 5
+
+// Bubble is a speech bubble with a tail around children.
+func Bubble(c *ui.Context, o BubbleOptions, children func()) *ui.Element {
+	if o.Tail > Right {
+		panic(fmt.Sprintf("display: unknown Side %d", o.Tail))
+	}
+	k := pixel.K(c)
+	at := orDef("Bubble At", o.At, 8)
+	pad := [4]int{6, 8, 6, 8}
+	pad[[...]int{Bottom: 2, Top: 0, Left: 3, Right: 1}[o.Tail]] += tailLen
+	return ui.Column(c).Padding(k.D(pad[0]), k.D(pad[1]), k.D(pad[2]), k.D(pad[3])).Draw(func(p *ui.Painter, r ui.Rect) {
+		g := k.Canvas(p, r)
+		x, y, w, h := 0, 0, g.W, g.H
+		switch o.Tail {
+		case Bottom:
+			h -= tailLen
+		case Top:
+			y, h = tailLen, h-tailLen
+		case Left:
+			x, w = tailLen, w-tailLen
+		case Right:
+			w -= tailLen
+		}
+		if w < 6 || h < 6 {
+			return
+		}
+		g.Frame(x, y, w, h, pixel.Notched, pixel.Lit)
+		for i := range tailLen {
+			n := tailLen - i
+			switch o.Tail {
+			case Bottom:
+				g.HLine(x+at-1, y+h-1+i, n+1, pixel.Edge)
+				g.HLine(x+at, y+h-1+i, n-1, pixel.Lit)
+			case Top:
+				g.HLine(x+at-1, y-i, n+1, pixel.Edge)
+				g.HLine(x+at, y-i, n-1, pixel.Lit)
+			case Left:
+				g.VLine(x-i, y+at-1, n+1, pixel.Edge)
+				g.VLine(x-i, y+at, n-1, pixel.Lit)
+			case Right:
+				g.VLine(x+w-1+i, y+at-1, n+1, pixel.Edge)
+				g.VLine(x+w-1+i, y+at, n-1, pixel.Lit)
+			}
+		}
+	}).Children(children)
+}