driver: Remove Graphics.SetWindow

Fixes #1026

internal/driver/graphics.go

@@ -15,8 +15,6 @@
 package driver
 
 import (
-	"unsafe"
-
 	"github.com/hajimehoshi/ebiten/internal/affine"
 	"github.com/hajimehoshi/ebiten/internal/thread"
 )
@@ -25,7 +23,6 @@ type Graphics interface {
 	SetThread(thread *thread.Thread)
 	Begin()
 	End()
-	SetWindow(window unsafe.Pointer)
 	SetTransparent(transparent bool)
 	SetVertices(vertices []float32, indices []uint16)
 	NewImage(width, height int) (Image, error)

internal/graphicsdriver/opengl/driver.go

@@ -16,7 +16,6 @@ package opengl
 
 import (
 	"fmt"
-	"unsafe"
 
 	"github.com/hajimehoshi/ebiten/internal/affine"
 	"github.com/hajimehoshi/ebiten/internal/driver"
@@ -52,10 +51,6 @@ func (d *Driver) End() {
 	d.context.flush()
 }
 
-func (d *Driver) SetWindow(window unsafe.Pointer) {
-	// Do nothing.
-}
-
 func (d *Driver) SetTransparent(transparent bool) {
 	// Do nothings.
 }

internal/uidriver/glfw/ui.go

@@ -650,7 +650,9 @@ func (u *UserInterface) run(context driver.UIContext) error {
 		w = u.nativeWindow()
 		return nil
 	})
-	u.Graphics().SetWindow(w)
+	if g, ok := u.Graphics().(interface{ SetWindow(unsafe.Pointer) }); ok {
+		g.SetWindow(w)
+	}
 	return u.loop(context)
 }
 
@@ -948,7 +950,9 @@ func (u *UserInterface) setWindowSize(width, height int, fullscreen bool, vsync
 	})
 
 	if windowRecreated {
-		u.Graphics().SetWindow(u.nativeWindow())
+		if g, ok := u.Graphics().(interface{ SetWindow(unsafe.Pointer) }); ok {
+			g.SetWindow(u.nativeWindow())
+		}
 	}
 }