internal/graphicsdriver: remove NeedsRestoring()

Updates #805

internal/graphicsdriver/directx/graphics11_windows.go

@@ -463,10 +463,6 @@ func (g *graphics11) SetVsyncEnabled(enabled bool) {
 	g.vsyncEnabled = enabled
 }
 
-func (g *graphics11) NeedsRestoring() bool {
-	return false
-}
-
 func (g *graphics11) NeedsClearingScreen() bool {
 	// TODO: Confirm this is really true.
 	return true

internal/graphicsdriver/directx/graphics12_windows.go

@@ -1054,10 +1054,6 @@ func (g *graphics12) SetVsyncEnabled(enabled bool) {
 	g.vsyncEnabled = enabled
 }
 
-func (g *graphics12) NeedsRestoring() bool {
-	return false
-}
-
 func (g *graphics12) NeedsClearingScreen() bool {
 	// TODO: Confirm this is really true.
 	return true

internal/graphicsdriver/graphics.go

@@ -62,7 +62,6 @@ type Graphics interface {
 	NewImage(width, height int) (Image, error)
 	NewScreenFramebufferImage(width, height int) (Image, error)
 	SetVsyncEnabled(enabled bool)
-	NeedsRestoring() bool
 	NeedsClearingScreen() bool
 	MaxImageSize() int
 

internal/graphicsdriver/metal/graphics_darwin.go

@@ -708,10 +708,6 @@ func (g *Graphics) SetVsyncEnabled(enabled bool) {
 	g.view.setDisplaySyncEnabled(enabled)
 }
 
-func (g *Graphics) NeedsRestoring() bool {
-	return false
-}
-
 func (g *Graphics) NeedsClearingScreen() bool {
 	return false
 }

internal/graphicsdriver/opengl/graphics.go

@@ -18,7 +18,6 @@ package opengl
 
 import (
 	"fmt"
-	"runtime"
 	"unsafe"
 
 	"github.com/hajimehoshi/ebiten/v2/internal/graphics"
@@ -310,20 +309,6 @@ func (g *Graphics) SetVsyncEnabled(enabled bool) {
 	g.vsync = enabled
 }
 
-func (g *Graphics) NeedsRestoring() bool {
-	// Though it is possible to have a logic to restore the graphics data for GPU, do not use it for performance (#1603).
-	if runtime.GOOS == "js" {
-		return false
-	}
-	// On Android, `setPreserveEGLContextOnPause(true)` is called and then context loss unlikely happens.
-	// If this happens, Ebitengine tries to relaunch the app (#805).
-	if runtime.GOOS == "android" {
-		return false
-	}
-	// TODO: Remove the entire logic of the restoring (#805).
-	return g.context.ctx.IsES()
-}
-
 func (g *Graphics) NeedsClearingScreen() bool {
 	return true
 }

internal/restorable/images.go

@@ -23,11 +23,9 @@ import (
 // forceRestoring reports whether restoring forcely happens or not.
 var forceRestoring = false
 
-var needsRestoringByGraphicsDriver bool
-
 // needsRestoring reports whether restoring process works or not.
 func needsRestoring() bool {
-	return forceRestoring || needsRestoringByGraphicsDriver
+	return forceRestoring
 }
 
 // AlwaysReadPixelsFromGPU reports whether ReadPixels always reads pixels from GPU or not.
@@ -266,7 +264,6 @@ var graphicsDriverInitialized bool
 // InitializeGraphicsDriverState initializes the graphics driver state.
 func InitializeGraphicsDriverState(graphicsDriver graphicsdriver.Graphics) error {
 	graphicsDriverInitialized = true
-	needsRestoringByGraphicsDriver = graphicsDriver.NeedsRestoring()
 	return graphicscommand.InitializeGraphicsDriverState(graphicsDriver)
 }