Add loadimage_js.go

ebitenutil/loadimage.go

@@ -12,6 +12,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+// +build !js
+
 package ebitenutil
 
 import (

ebitenutil/loadimage_js.go

@@ -0,0 +1,66 @@
+// 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.
+
+// +build js
+
+package ebitenutil
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"github.com/gopherjs/gopherjs/js"
+	"github.com/hajimehoshi/ebiten"
+	"image"
+)
+
+func NewImageFromFile(path string, filter ebiten.Filter) (*ebiten.Image, image.Image, error) {
+	var err error
+	var content js.Object
+	ch := make(chan struct{})
+	req := js.Global.Get("XMLHttpRequest").New()
+	req.Set("responseType", "arraybuffer")
+	req.Call("open", "GET", path, true)
+	req.Set("onload", func() {
+		defer close(ch)
+		status := req.Get("status").Int()
+		if 200 <= status && status < 400 {
+			content = req.Get("response")
+			return
+		}
+		err = errors.New(fmt.Sprintf("http error: %d", status))
+	})
+	req.Set("onerror", func() {
+		defer close(ch)
+		// TODO: Add more information.
+		err = errors.New("http error")
+	})
+	req.Call("send")
+	<-ch
+	if err != nil {
+		return nil, nil, err
+	}
+
+	data := js.Global.Get("Uint8Array").New(content).Interface().([]uint8)
+	b := bytes.NewBuffer(data)
+	img, _, err := image.Decode(b)
+	if err != nil {
+		return nil, nil, err
+	}
+	img2, err := ebiten.NewImageFromImage(img, filter)
+	if err != nil {
+		return nil, nil, err
+	}
+	return img2, img, nil
+}

internal/opengl/context.go

@@ -46,7 +46,6 @@ func NewContext() *Context {
 
 func (c *Context) init() {
 	gl.Init()
-	gl.Enable(gl.TEXTURE_2D)
 	// Textures' pixel formats are alpha premultiplied.
 	gl.Enable(gl.BLEND)
 	gl.BlendFunc(gl.ONE, gl.ONE_MINUS_SRC_ALPHA)

internal/opengl/context_js.go

@@ -50,7 +50,6 @@ func NewContext(gl *webgl.Context) *Context {
 
 func (c *Context) init() {
 	gl := c.gl
-	gl.Enable(gl.TEXTURE_2D)
 	// Textures' pixel formats are alpha premultiplied.
 	gl.Enable(gl.BLEND)
 	gl.BlendFunc(gl.ONE, gl.ONE_MINUS_SRC_ALPHA)

internal/opengl/types.go

@@ -28,5 +28,5 @@ type Context struct {
 	ElementArrayBuffer BufferType
 	DynamicDraw        BufferUsageType
 	StaticDraw         BufferUsageType
-	*context
+	context
 }

internal/ui/ui_js.go

@@ -47,8 +47,17 @@ func SwapBuffers() {
 }
 
 func init() {
-	canvas = js.Global.Get("Canvas").New()
+	ch := make(chan struct{})
-	js.Global.Get("document").Get("body").Call("appendChild", canvas)
+	js.Global.Get("window").Set("onload", func() {
+		close(ch)
+	})
+	<-ch
+
+	doc := js.Global.Get("document")
+	canvas = doc.Call("createElement", "canvas")
+	canvas.Set("width", 16)
+	canvas.Set("height", 16)
+	doc.Get("body").Call("appendChild", canvas)
 	webglContext, err := webgl.NewContext(canvas, &webgl.ContextAttributes{
 		Alpha:              true,
 		PremultipliedAlpha: true,
@@ -60,5 +69,7 @@ func init() {
 }
 
 func Start(width, height, scale int, title string) (actualScale int, err error) {
+	canvas.Set("width", width*scale)
+	canvas.Set("height", height*scale)
 	return scale, nil
 }