driver: Move ui.RegularTermination to driver

internal/driver/ui.go

@@ -14,7 +14,16 @@
 
 package driver
 
+import (
+	"errors"
+)
+
 type GraphicsContext interface {
 	SetSize(width, height int, scale float64)
 	Update(afterFrameUpdate func()) error
 }
+
+// RegularTermination represents a regular termination.
+// Run can return this error, and if this error is received,
+// the game loop should be terminated as soon as possible.
+var RegularTermination = errors.New("regular termination")

internal/ui/ui.go

@@ -1,24 +0,0 @@
-// Copyright 2015 Hajime Hoshi
-//
-// 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 ui
-
-import (
-	"errors"
-)
-
-// RegularTermination represents a regular termination.
-// Run can return this error, and if this error is received,
-// the game loop should be terminated as soon as possible.
-var RegularTermination = errors.New("regular termination")

internal/ui/ui_glfw.go

@@ -745,7 +745,7 @@ func (u *userInterface) update(g driver.GraphicsContext) error {
 		return nil
 	})
 	if shouldClose {
-		return RegularTermination
+		return driver.RegularTermination
 	}
 
 	_ = mainthread.Run(func() error {

run.go

@@ -19,6 +19,7 @@ import (
 	"sync/atomic"
 
 	"github.com/hajimehoshi/ebiten/internal/clock"
+	"github.com/hajimehoshi/ebiten/internal/driver"
 	"github.com/hajimehoshi/ebiten/internal/input"
 	"github.com/hajimehoshi/ebiten/internal/ui"
 	"github.com/hajimehoshi/ebiten/internal/web"
@@ -98,7 +99,7 @@ func run(width, height int, scale float64, title string, g *graphicsContext, mai
 		defer atomic.StoreInt32(&isRunning, 0)
 	}
 	if err := ui.Run(width, height, scale, title, g, mainloop, graphicsDriver(), input.Get()); err != nil {
-		if err == ui.RegularTermination {
+		if err == driver.RegularTermination {
 			return nil
 		}
 		return err