diff --git a/image.go b/image.go
index b96157d4f..75c2ce55d 100644
--- a/image.go
+++ b/image.go
@@ -246,7 +246,7 @@ func (i *Image) DrawImage(img *Image, options *DrawImageOptions) error {
 		filter = graphics.Filter(img.filter)
 	}
 
-	i.sharedImagePart.image().DrawImage(img.sharedImagePart.image(), sx0, sy0, sx1, sy1, geom, options.ColorM.impl, mode, filter)
+	i.sharedImagePart.DrawImage(img.sharedImagePart, sx0, sy0, sx1, sy1, geom, options.ColorM.impl, mode, filter)
 	return nil
 }
 
@@ -276,7 +276,7 @@ func (i *Image) At(x, y int) color.Color {
 	if x < 0 || y < 0 || x >= w || y >= h {
 		return color.RGBA{}
 	}
-	clr, err := i.sharedImagePart.image().At(x+ox, y+oy)
+	clr, err := i.sharedImagePart.At(x+ox, y+oy)
 	if err != nil {
 		panic(err)
 	}
@@ -321,7 +321,7 @@ func (i *Image) ReplacePixels(p []byte) error {
 	if l := 4 * w * h; len(p) != l {
 		panic(fmt.Sprintf("ebiten: len(p) was %d but must be %d", len(p), l))
 	}
-	i.sharedImagePart.image().ReplacePixels(p, x, y, w, h)
+	i.sharedImagePart.ReplacePixels(p, x, y, w, h)
 	return nil
 }
 
diff --git a/shared.go b/shared.go
index 231f396dd..c0bdbf977 100644
--- a/shared.go
+++ b/shared.go
@@ -15,6 +15,9 @@
 package ebiten
 
 import (
+	"image/color"
+
+	"github.com/hajimehoshi/ebiten/internal/affine"
 	"github.com/hajimehoshi/ebiten/internal/graphics"
 	"github.com/hajimehoshi/ebiten/internal/opengl"
 	"github.com/hajimehoshi/ebiten/internal/packing"
@@ -53,10 +56,6 @@ func (s *sharedImagePart) ensureNotShared() {
 	}
 }
 
-func (s *sharedImagePart) image() *restorable.Image {
-	return s.sharedImage.restorable
-}
-
 func (s *sharedImagePart) region() (x, y, width, height int) {
 	if s.node == nil {
 		w, h := s.sharedImage.restorable.Size()
@@ -65,6 +64,18 @@ func (s *sharedImagePart) region() (x, y, width, height int) {
 	return s.node.Region()
 }
 
+func (s *sharedImagePart) DrawImage(img *sharedImagePart, sx0, sy0, sx1, sy1 int, geom *affine.GeoM, colorm *affine.ColorM, mode opengl.CompositeMode, filter graphics.Filter) {
+	s.sharedImage.restorable.DrawImage(img.sharedImage.restorable, sx0, sy0, sx1, sy1, geom, colorm, mode, filter)
+}
+
+func (s *sharedImagePart) ReplacePixels(pixels []byte, x, y, width, height int) {
+	s.sharedImage.restorable.ReplacePixels(pixels, x, y, width, height)
+}
+
+func (s *sharedImagePart) At(x, y int) (color.Color, error) {
+	return s.sharedImage.restorable.At(x, y)
+}
+
 func (s *sharedImagePart) isDisposed() bool {
 	return s.sharedImage == nil
 }