Revert "internal/atlas: move some functions in internal/restorable to internal/atlas"

This reverts commit 3651d73e0b.

Updates #3083

internal/atlas/image.go

@@ -141,8 +141,6 @@ var (
 
 	imagesUsedAsDestination smallImageSet
 
-	graphicsDriverInitialized bool
-
 	deferred []func()
 
 	// deferredM is a mutex for the slice operations. This must not be used for other usages.
@@ -655,10 +653,6 @@ func (i *Image) finalize() {
 }
 
 func (i *Image) allocate(forbiddenBackends []*backend, asSource bool) {
-	if !graphicsDriverInitialized {
-		panic("atlas: graphics driver must be ready at allocate but not")
-	}
-
 	if i.backend != nil {
 		panic("atlas: the image is already allocated")
 	}
@@ -821,7 +815,7 @@ func BeginFrame(graphicsDriver graphicsdriver.Graphics) error {
 
 	var err error
 	initOnce.Do(func() {
-		err = graphicscommand.InitializeGraphicsDriverState(graphicsDriver)
+		err = restorable.InitializeGraphicsDriverState(graphicsDriver)
 		if err != nil {
 			return
 		}
@@ -837,10 +831,8 @@ func BeginFrame(graphicsDriver graphicsdriver.Graphics) error {
 			minDestinationSize = 16
 		}
 		if maxSize == 0 {
-			maxSize = floorPowerOf2(graphicscommand.MaxImageSize(graphicsDriver))
+			maxSize = floorPowerOf2(restorable.MaxImageSize(graphicsDriver))
 		}
-
-		graphicsDriverInitialized = true
 	})
 	if err != nil {
 		return err

internal/restorable/image.go

@@ -52,6 +52,10 @@ type Image struct {
 //
 // Note that Dispose is not called automatically.
 func NewImage(width, height int, imageType ImageType) *Image {
+	if !graphicsDriverInitialized {
+		panic("restorable: graphics driver must be ready at NewImage but not")
+	}
+
 	i := &Image{
 		Image:     graphicscommand.NewImage(width, height, imageType == ImageTypeScreen),
 		width:     width,

internal/restorable/images.go

@@ -0,0 +1,33 @@
+// Copyright 2017 The Ebiten Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package restorable
+
+import (
+	"github.com/hajimehoshi/ebiten/v2/internal/graphicscommand"
+	"github.com/hajimehoshi/ebiten/v2/internal/graphicsdriver"
+)
+
+var graphicsDriverInitialized bool
+
+// InitializeGraphicsDriverState initializes the graphics driver state.
+func InitializeGraphicsDriverState(graphicsDriver graphicsdriver.Graphics) error {
+	graphicsDriverInitialized = true
+	return graphicscommand.InitializeGraphicsDriverState(graphicsDriver)
+}
+
+// MaxImageSize returns the maximum size of an image.
+func MaxImageSize(graphicsDriver graphicsdriver.Graphics) int {
+	return graphicscommand.MaxImageSize(graphicsDriver)
+}