ebitenutil: Add NewImageFromURL

ebitenutil/url.go

@@ -0,0 +1,44 @@
+// Copyright 2018 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 ebitenutil
+
+import (
+	"image"
+	"net/http"
+
+	"github.com/hajimehoshi/ebiten"
+)
+
+// NewImageFromURL creates a new ebiten.Image from the given URL.
+//
+// Image decoders must be imported when using this function. For example,
+// if you want to load a PNG image, you'd need to add `_ "image/png"` to the import section.
+//
+// FilterDefault is used at NewImgeFromImage internally.
+func NewImageFromURL(url string) (*ebiten.Image, error) {
+	res, err := http.Get(url)
+	if err != nil {
+		return nil, err
+	}
+	defer res.Body.Close()
+
+	img, _, err := image.Decode(res.Body)
+	if err != nil {
+		return nil, err
+	}
+
+	eimg, _ := ebiten.NewImageFromImage(img, ebiten.FilterDefault)
+	return eimg, nil
+}

examples/highdpi/main.go

@@ -18,10 +18,8 @@ package main
 
 import (
 	"fmt"
-	"image"
 	_ "image/jpeg"
 	"log"
-	"net/http"
 
 	"github.com/hajimehoshi/ebiten"
 	"github.com/hajimehoshi/ebiten/ebitenutil"
@@ -40,23 +38,11 @@ func init() {
 
 	// Load the image asynchronously.
 	go func() {
-		res, err := http.Get(url)
+		img, err := ebitenutil.NewImageFromURL(url)
 		if err != nil {
 			log.Fatal(err)
 		}
-		defer res.Body.Close()
+		highDPIImageCh <- img
-
-		img, _, err := image.Decode(res.Body)
-		if err != nil {
-			log.Fatal(err)
-		}
-
-		eimg, err := ebiten.NewImageFromImage(img, ebiten.FilterDefault)
-		if err != nil {
-			log.Fatal(err)
-		}
-
-		highDPIImageCh <- eimg
 		close(highDPIImageCh)
 	}()
 }