cleaning up the component system just a bit more...

common/elements/v1/element.go

@@ -4,8 +4,6 @@ import (
 	"github.com/hajimehoshi/ebiten/v2"
 )
 
-type InitFunc func() Element
-
 type Element interface {
 	Draw(*ebiten.Image)
 	SetAnchor(Point)
@@ -40,3 +38,26 @@ type Bounds struct {
 func (b *Bounds) Contains(p Point) bool {
 	return p.X >= b.Min.X && p.X <= b.Min.X+b.Width && p.Y >= b.Min.Y && p.Y <= b.Min.Y+b.Height
 }
+
+type Core struct {
+	anchor   Point
+	children []Element
+
+	name string // For debugging
+}
+
+func (c *Core) Anchor() Point {
+	return c.anchor
+}
+
+func (c *Core) SetAnchor(a Point) {
+	d := c.Anchor().Delta(a)
+	for _, ch := range c.Children() {
+		ch.SetAnchor(ch.Anchor().Add(d))
+	}
+	c.anchor = a
+}
+
+func (c *Core) Children() []Element {
+	return c.children
+}