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

display/display.go

@@ -0,0 +1,54 @@
+// Package display shows things: pictures, faces, badges and prizes.
+package display
+
+import (
+	"fmt"
+
+	"github.com/egoist/mygo/ui"
+
+	"git.zacharyzhang.com/ZacharyZhang-NY/8bitMyGoUI/pixel"
+)
+
+// art is a labeled w×h dot image that fn draws.
+func art(c *ui.Context, k pixel.Kit, label string, w, h int, fn func(g pixel.Canvas)) *ui.Element {
+	e := ui.Box(c).Size(k.D(w), k.D(h))
+	if label != "" {
+		e.Label(label).Role(ui.RoleImage)
+	} else {
+		e.Role(ui.RoleNone)
+	}
+	if fn != nil {
+		e.Draw(func(p *ui.Painter, r ui.Rect) { fn(k.Canvas(p, r)) })
+	}
+	return e
+}
+
+// orDef is v, or def for zero; negative panics.
+func orDef(name string, v, def int) int {
+	if v < 0 {
+		panic(fmt.Sprintf("display: %s %d is negative", name, v))
+	}
+	if v == 0 {
+		return def
+	}
+	return v
+}
+
+// scale is s, or 1 for zero; outside 1–4 panics.
+func scale(s int) int {
+	s = orDef("Scale", s, 1)
+	if s > 4 {
+		panic(fmt.Sprintf("display: Scale %d outside 1–4", s))
+	}
+	return s
+}
+
+// slotOr is s, or def for the zero slot.
+func slotOr(s, def pixel.Slot) pixel.Slot {
+	if s == pixel.Ink {
+		return def
+	}
+	return s
+}
+
+func itoa(n int) string { return fmt.Sprint(n) }