Media: components 341-360

camera_preview.go

@@ -0,0 +1,93 @@
+package mujica
+
+import (
+	"image"
+	"log/slog"
+
+	"github.com/egoist/mygo/ui"
+
+	"mujicaui/internal"
+	"mujicaui/theme"
+)
+
+// CameraFrame is the caller's latest camera picture.
+type CameraFrame struct {
+	// Image is the frame; nil shows "No signal".
+	Image image.Image
+	// Seq numbers frames; a new number redraws a reused Image.
+	Seq uint64
+}
+
+// CameraPreviewOptions configure a CameraPreview.
+type CameraPreviewOptions struct {
+	// Label names the camera for assistive technology.
+	Label    string
+	Disabled bool
+}
+
+type cameraCache struct {
+	img    image.Image
+	seq    uint64
+	mirror bool
+	bmp    *ui.Bitmap
+}
+
+type cameraKey struct{}
+
+// CameraPreview shows frame at 16:9, mirrored while *mirror.
+func CameraPreview(c *ui.Context, frame CameraFrame, mirror *bool, opts CameraPreviewOptions) ChoiceResult {
+	k := Tokens(c)
+	old := *mirror
+	label := opts.Label
+	if label == "" {
+		label = msg(c, "camera_preview.label")
+	}
+	box := ui.Box(c).FillWidth().AspectRatio(16.0 / 9).Background(videoBlack).Radius(theme.CardRadius).Clip().
+		Center().Focusable().Role(ui.RoleImage).Label(label).Disabled(opts.Disabled)
+	internal.Ring(box, k.Focus, theme.CardRadius)
+	cache := ui.Local(box, cameraKey{}, func() cameraCache { return cameraCache{} })
+	box.Children(func() {
+		if frame.Image == nil {
+			box.Description(msg(c, "camera_preview.noSignal"))
+			ui.Column(c).Gap(8).AlignItems(ui.Center).Children(func() {
+				ui.Icon(c, mediaCamera).Size(28, 28).TextColor(ui.Hex("#BCAEAA"))
+				ui.Text(c, msg(c, "camera_preview.noSignal")).TextColor(ui.Hex("#BCAEAA"))
+			})
+		} else {
+			// Copies are made once per frame number, not per paint.
+			if cache.img != frame.Image || cache.seq != frame.Seq || cache.mirror != *mirror || cache.bmp == nil {
+				*cache = cameraCache{frame.Image, frame.Seq, *mirror, cameraBitmap(frame.Image, *mirror)}
+			}
+			ui.Image(c, cache.bmp).Fit(ui.Contain).Fill()
+		}
+		ui.Box(c).Absolute().Top(8).Right(8).Background(ui.RGBA(0, 0, 0, 0.5)).Radius(theme.ControlRadius).Children(func() {
+			b := mediaToggleAction(c, mediaMirror, msg(c, "camera_preview.mirror"), *mirror)
+			if b.Clicked() && !b.IsDisabled() {
+				*mirror = !*mirror
+			}
+		})
+	})
+	if !box.IsDisabled() && box.Shortcut(0, ui.KeyM) {
+		*mirror = !*mirror
+	}
+	changed := *mirror != old
+	if changed {
+		slog.Debug("mujica: camera_preview mirror", "on", *mirror)
+	}
+	return ChoiceResult{Element: box, changed: changed}
+}
+
+// cameraBitmap copies img into a bitmap, flipped when mirror.
+func cameraBitmap(img image.Image, mirror bool) *ui.Bitmap {
+	if !mirror {
+		return ui.NewBitmap(img)
+	}
+	b := img.Bounds()
+	out := image.NewRGBA(image.Rect(0, 0, b.Dx(), b.Dy()))
+	for y := b.Min.Y; y < b.Max.Y; y++ {
+		for x := b.Min.X; x < b.Max.X; x++ {
+			out.Set(b.Max.X-1-x, y-b.Min.Y, img.At(x, y))
+		}
+	}
+	return ui.NewBitmap(out)
+}