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

display/signpost.go

@@ -0,0 +1,93 @@
+package display
+
+import (
+	"fmt"
+	"log/slog"
+
+	"github.com/egoist/mygo/ui"
+
+	"git.zacharyzhang.com/ZacharyZhang-NY/8bitMyGoUI/pixel"
+)
+
+type SignpostOptions struct {
+	Disabled bool
+}
+
+type SignpostResult struct {
+	Element *ui.Element
+	// Clicked is the board clicked this frame, or -1.
+	Clicked int
+}
+
+// Signpost is a post with one to three arrow boards.
+func Signpost(c *ui.Context, boards []string, o SignpostOptions) SignpostResult {
+	if len(boards) < 1 || len(boards) > 3 {
+		panic(fmt.Sprintf("display: Signpost needs 1–3 boards, got %d", len(boards)))
+	}
+	k := pixel.K(c)
+	w := 0
+	for _, b := range boards {
+		w = max(w, pixel.Measure(b))
+	}
+	w += 18
+	res := SignpostResult{Clicked: -1}
+	res.Element = ui.Column(c).Width(k.D(w+8)).Gap(k.D(3)).AlignItems(ui.Center).Padding(0, 0, k.D(20), 0).Role(ui.RoleGroup).FocusGroup(ui.Vertical).Draw(func(p *ui.Painter, r ui.Rect) {
+		g := k.Canvas(p, r)
+		g.Rect(g.W/2-2, 2, 4, g.H-2, pixel.Shade)
+		g.VLine(g.W/2-2, 2, g.H-2, pixel.Edge)
+		g.VLine(g.W/2+1, 2, g.H-2, pixel.Edge)
+	}).Children(func() {
+		for i, b := range boards {
+			if board(c, k, b, w, i%2 == 1, o.Disabled) {
+				res.Clicked = i
+			}
+		}
+	})
+	if res.Clicked >= 0 {
+		slog.Debug("8bit: signpost", "board", boards[res.Clicked])
+	}
+	return res
+}
+
+// board is one wooden arrow, pointing left if asked.
+func board(c *ui.Context, k pixel.Kit, label string, w int, left, disabled bool) bool {
+	shell, base, st := pixel.Shell(c, func() *ui.Element { return ui.ButtonBase(c).Label(label).Disabled(disabled) })
+	h := pixel.LineHeight + 2
+	shell.Size(k.D(w), k.D(h)).Draw(func(p *ui.Painter, r ui.Rect) {
+		g := k.Canvas(p, r)
+		dy := 0
+		if st.Press {
+			dy = 1
+		}
+		for j := range h - dy {
+			cut := abs(j - (h-1)/2)
+			x0, x1 := 0, w-cut
+			if left {
+				x0, x1 = cut, w
+			}
+			fill := pixel.Warn
+			if j == 0 || j == h-1-dy {
+				fill = pixel.Edge
+			}
+			g.HLine(x0, j+dy, x1-x0, fill)
+			g.Dot(x0, j+dy, pixel.Edge)
+			g.Dot(x1-1, j+dy, pixel.Edge)
+		}
+		g.Veil(1, 1+dy, w-2, h-3, pixel.Shade, 4)
+		tx := 6
+		if left {
+			tx = w - 6 - pixel.Measure(label)
+		}
+		g.Text(tx, 1+dy, label, pixel.Ink, 1)
+		if st.Hover {
+			g.Veil(1, 1+dy, w-2, h-3, pixel.Lit, 4)
+		}
+		if st.Disabled {
+			g.Checker(0, 0, w, h, pixel.Face)
+		}
+		if st.Focus {
+			g.FocusMark(0, 0, w, h)
+		}
+	})
+	return base.Clicked()
+}