Get the bridge door animations running

internal/ui/noninteractive.go

@@ -15,6 +15,7 @@ func init() {
 	registerBuilder(menus.TypeHypertext, registerHypertext)
 	registerBuilder(menus.TypeOverlay, registerOverlay)
 	registerBuilder(menus.TypeAnimationSample, registerAnimation)
+	registerBuilder(menus.TypeAnimationHover, registerDebug("WIP AnimationHover", registerAnimationHover))
 }
 
 // A non-interactive element is not a widget; it merely displays some pixels and
@@ -31,6 +32,17 @@ type noninteractive struct {
 	hoverImpl
 }
 
+// This particular animation has entry and exit sequences, which are invoked
+// when entering and leaving hover, respectively. Example: bridge doors
+type animationHover struct {
+	noninteractive           // Use the frames in here for the "enter hover" animation
+	exitFrames     animation // and here the "exit hover" animation
+
+	atTick  int // Tracks progress through the frames
+	opening bool
+	closing bool
+}
+
 func registerStatic(d *Driver, r *menus.Record) error {
 	// FIXME: SpriteID takes precedence over SHARE if present, but is that right?
 	spriteId := r.Share
@@ -125,6 +137,38 @@ func registerAnimation(d *Driver, r *menus.Record) error {
 	return nil
 }
 
+func registerAnimationHover(d *Driver, r *menus.Record) error {
+	sprite, err := d.menu.Sprite(r.SpriteId[0])
+	if err != nil {
+		return err
+	}
+
+	enterFrames, err := d.menu.Images(r.SpriteId[0], r.DrawType)
+	if err != nil {
+		return err
+	}
+
+	exitFrames, err := d.menu.Images(r.SpriteId[0]+r.DrawType, r.DrawType)
+	if err != nil {
+		return err
+	}
+
+	ani := &animationHover{
+		noninteractive: noninteractive{
+			frames:    animation(enterFrames),
+			hoverImpl: hoverImpl{text: r.Text},
+			rect:      sprite.Rect,
+		},
+
+		exitFrames: animation(exitFrames),
+	}
+
+	d.hoverables = append(d.hoverables, ani)
+	d.paintables = append(d.paintables, ani)
+
+	return nil
+}
+
 func (n *noninteractive) bounds() image.Rectangle {
 	return n.rect
 }
@@ -138,3 +182,35 @@ func (n *noninteractive) regions(tick int) []region {
 
 	return out
 }
+
+func (a *animationHover) regions(tick int) []region {
+	if a.opening || a.closing {
+		var anim animation
+		if a.opening {
+			anim = a.frames
+		} else {
+			anim = a.exitFrames
+		}
+
+		out := oneRegion(a.bounds().Min, anim[a.atTick])
+
+		if a.atTick < len(anim)-1 {
+			a.atTick += 1
+		} else if !a.hoverState() {
+			a.closing = false
+		}
+
+		return out
+	}
+
+	// Nothing doing, show a closed door
+	return oneRegion(a.bounds().Min, a.frames.image(0))
+}
+
+func (a *animationHover) setHoverState(value bool) {
+	a.atTick = 0
+	a.opening = value
+	a.closing = !value
+
+	a.hoverImpl.setHoverState(value)
+}