graphics: Reduce imageM usages

image.go

@@ -207,8 +207,6 @@ func NewImage(width, height int, filter Filter) (*Image, error) {
 	if err != nil {
 		return nil, err
 	}
-	imageM.Lock()
-	defer imageM.Unlock()
 	image.image, err = graphics.NewImage(width, height, glFilter(filter))
 	if err != nil {
 		return nil, err
@@ -247,8 +245,6 @@ func NewImageFromImage(source image.Image, filter Filter) (*Image, error) {
 		filter: filter,
 		pixels: pixels,
 	}
-	imageM.Lock()
-	defer imageM.Unlock()
 	var err error
 	img.image, err = graphics.NewImageFromImage(rgbaImg, glFilter(filter))
 	if err != nil {
@@ -264,8 +260,6 @@ func NewImageFromImage(source image.Image, filter Filter) (*Image, error) {
 }
 
 func newImageWithScreenFramebuffer(width, height int) (*Image, error) {
-	imageM.Lock()
-	defer imageM.Unlock()
 	i, err := graphics.NewScreenFramebufferImage(width, height)
 	if err != nil {
 		return nil, err

imageimpl.go

@@ -41,11 +41,12 @@ type imageImpl struct {
 	filter   Filter
 	pixels   []uint8
 	noSave   bool
+	m        sync.Mutex
 }
 
 func (i *imageImpl) Fill(clr color.Color) error {
-	imageM.Lock()
-	defer imageM.Unlock()
+	i.m.Lock()
+	defer i.m.Unlock()
 	if i.isDisposed() {
 		return errors.New("ebiten: image is already disposed")
 	}
@@ -79,8 +80,8 @@ func (i *imageImpl) DrawImage(image *Image, options *DrawImageOptions) error {
 	if i == image.impl {
 		return errors.New("ebiten: Image.DrawImage: image should be different from the receiver")
 	}
-	imageM.Lock()
-	defer imageM.Unlock()
+	i.m.Lock()
+	defer i.m.Unlock()
 	if i.isDisposed() {
 		return errors.New("ebiten: image is already disposed")
 	}
@@ -161,8 +162,8 @@ func (i *imageImpl) restorePixels() error {
 }
 
 func (i *imageImpl) Dispose() error {
-	imageM.Lock()
-	defer imageM.Unlock()
+	i.m.Lock()
+	defer i.m.Unlock()
 	if i.isDisposed() {
 		return errors.New("ebiten: image is already disposed")
 	}
@@ -184,8 +185,8 @@ func (i *imageImpl) ReplacePixels(p []uint8) error {
 	if l := 4 * i.width * i.height; len(p) != l {
 		return fmt.Errorf("ebiten: p's length must be %d", l)
 	}
-	imageM.Lock()
-	defer imageM.Unlock()
+	i.m.Lock()
+	defer i.m.Unlock()
 	if i.pixels == nil {
 		i.pixels = make([]uint8, len(p))
 	}

internal/graphics/command.go

@@ -21,6 +21,7 @@ import (
 	"image/color"
 	"image/draw"
 	"math"
+	"sync"
 
 	"github.com/hajimehoshi/ebiten/internal/graphics/opengl"
 )
@@ -32,6 +33,7 @@ type command interface {
 type commandQueue struct {
 	commands           []command
 	indexOffsetInBytes int
+	m                  sync.Mutex
 }
 
 var theCommandQueue = &commandQueue{
@@ -39,10 +41,14 @@ var theCommandQueue = &commandQueue{
 }
 
 func (q *commandQueue) Enqueue(command command) {
+	q.m.Lock()
+	defer q.m.Unlock()
 	q.commands = append(q.commands, command)
 }
 
 func (q *commandQueue) Flush(context *opengl.Context) error {
+	q.m.Lock()
+	defer q.m.Unlock()
 	// glViewport must be called at least at every frame on iOS.
 	context.ResetViewportSize()
 	q.indexOffsetInBytes = 0

internal/graphics/program.go

@@ -63,6 +63,8 @@ func (s *openGLState) initialize(context *opengl.Context) error {
 	s.lastColorMatrixTranslation = nil
 	s.lastTexture = zeroTexture
 
+	// TODO: Remove the old programs when resuming?
+
 	shaderVertexModelviewNative, err := context.NewShader(opengl.VertexShader, shader(context, shaderVertexModelview))
 	if err != nil {
 		panic(fmt.Sprintf("graphics: shader compiling error:\n%s", err))
@@ -83,6 +85,8 @@ func (s *openGLState) initialize(context *opengl.Context) error {
 		return err
 	}
 
+	// TODO: Remove the old buffers when resuming?
+
 	const stride = 8 // (2 [vertices] + 2 [texels]) * 2 [sizeof(int16)/bytes]
 	context.NewBuffer(opengl.ArrayBuffer, 4*stride*MaxQuads, opengl.DynamicDraw)