graphicsdriver/metal: Move MTLDevice and CAMetalLayer to the other struct

On iOS, they are given or included in a MTKView and we don't have
to (or should not) make them. Let's move them to a different
struct.

internal/graphicsdriver/metal/driver.go

@@ -283,10 +283,8 @@ type rpsKey struct {
 }
 
 type Driver struct {
-	window uintptr
+	view view
 
-	device    mtl.Device
-	ml        ca.MetalLayer
 	screenRPS mtl.RenderPipelineState
 	rpss      map[rpsKey]mtl.RenderPipelineState
 	cq        mtl.CommandQueue
@@ -339,8 +337,8 @@ func (d *Driver) End() {
 func (d *Driver) SetWindow(window uintptr) {
 	d.t.Call(func() error {
 		// Note that [NSApp mainWindow] returns nil when the window is borderless.
-		// Then the window is needed to be given.
-		d.window = window
+		// Then the window is needed to be given explicitly.
+		d.view.setWindow(window)
 		return nil
 	})
 }
@@ -353,8 +351,8 @@ func (d *Driver) SetVertices(vertices []float32, indices []uint16) {
 		if d.ib != (mtl.Buffer{}) {
 			d.ib.Release()
 		}
-		d.vb = d.device.MakeBufferWithBytes(unsafe.Pointer(&vertices[0]), unsafe.Sizeof(vertices[0])*uintptr(len(vertices)), mtl.ResourceStorageModeManaged)
-		d.ib = d.device.MakeBufferWithBytes(unsafe.Pointer(&indices[0]), unsafe.Sizeof(indices[0])*uintptr(len(indices)), mtl.ResourceStorageModeManaged)
+		d.vb = d.view.getMTLDevice().MakeBufferWithBytes(unsafe.Pointer(&vertices[0]), unsafe.Sizeof(vertices[0])*uintptr(len(vertices)), mtl.ResourceStorageModeManaged)
+		d.ib = d.view.getMTLDevice().MakeBufferWithBytes(unsafe.Pointer(&indices[0]), unsafe.Sizeof(indices[0])*uintptr(len(indices)), mtl.ResourceStorageModeManaged)
 		return nil
 	})
 }
@@ -390,25 +388,25 @@ func (d *Driver) checkSize(width, height int) {
 			d.maxImageSize = 4096
 			// https://developer.apple.com/metal/Metal-Feature-Set-Tables.pdf
 			switch {
-			case d.device.SupportsFeatureSet(mtl.FeatureSet_iOS_GPUFamily5_v1):
+			case d.view.getMTLDevice().SupportsFeatureSet(mtl.FeatureSet_iOS_GPUFamily5_v1):
 				d.maxImageSize = 16384
-			case d.device.SupportsFeatureSet(mtl.FeatureSet_iOS_GPUFamily4_v1):
+			case d.view.getMTLDevice().SupportsFeatureSet(mtl.FeatureSet_iOS_GPUFamily4_v1):
 				d.maxImageSize = 16384
-			case d.device.SupportsFeatureSet(mtl.FeatureSet_iOS_GPUFamily3_v1):
+			case d.view.getMTLDevice().SupportsFeatureSet(mtl.FeatureSet_iOS_GPUFamily3_v1):
 				d.maxImageSize = 16384
-			case d.device.SupportsFeatureSet(mtl.FeatureSet_iOS_GPUFamily2_v2):
+			case d.view.getMTLDevice().SupportsFeatureSet(mtl.FeatureSet_iOS_GPUFamily2_v2):
 				d.maxImageSize = 8192
-			case d.device.SupportsFeatureSet(mtl.FeatureSet_iOS_GPUFamily2_v1):
+			case d.view.getMTLDevice().SupportsFeatureSet(mtl.FeatureSet_iOS_GPUFamily2_v1):
 				d.maxImageSize = 4096
-			case d.device.SupportsFeatureSet(mtl.FeatureSet_iOS_GPUFamily1_v2):
+			case d.view.getMTLDevice().SupportsFeatureSet(mtl.FeatureSet_iOS_GPUFamily1_v2):
 				d.maxImageSize = 8192
-			case d.device.SupportsFeatureSet(mtl.FeatureSet_iOS_GPUFamily1_v1):
+			case d.view.getMTLDevice().SupportsFeatureSet(mtl.FeatureSet_iOS_GPUFamily1_v1):
 				d.maxImageSize = 4096
-			case d.device.SupportsFeatureSet(mtl.FeatureSet_tvOS_GPUFamily2_v1):
+			case d.view.getMTLDevice().SupportsFeatureSet(mtl.FeatureSet_tvOS_GPUFamily2_v1):
 				d.maxImageSize = 16384
-			case d.device.SupportsFeatureSet(mtl.FeatureSet_tvOS_GPUFamily1_v1):
+			case d.view.getMTLDevice().SupportsFeatureSet(mtl.FeatureSet_tvOS_GPUFamily1_v1):
 				d.maxImageSize = 8192
-			case d.device.SupportsFeatureSet(mtl.FeatureSet_macOS_GPUFamily1_v1):
+			case d.view.getMTLDevice().SupportsFeatureSet(mtl.FeatureSet_macOS_GPUFamily1_v1):
 				d.maxImageSize = 16384
 			default:
 				panic("metal: there is no supported feature set")
@@ -446,7 +444,7 @@ func (d *Driver) NewImage(width, height int) (driver.Image, error) {
 	}
 	var t mtl.Texture
 	d.t.Call(func() error {
-		t = d.device.MakeTexture(td)
+		t = d.view.getMTLDevice().MakeTexture(td)
 		return nil
 	})
 	return &Image{
@@ -459,7 +457,7 @@ func (d *Driver) NewImage(width, height int) (driver.Image, error) {
 
 func (d *Driver) NewScreenFramebufferImage(width, height int) (driver.Image, error) {
 	d.t.Call(func() error {
-		d.ml.SetDrawableSize(width, height)
+		d.view.setDrawableSize(width, height)
 		return nil
 	})
 	return &Image{
@@ -482,22 +480,10 @@ func (d *Driver) Reset() error {
 			d.rpss = map[rpsKey]mtl.RenderPipelineState{}
 		}
 
-		var err error
-		d.device, err = mtl.CreateSystemDefaultDevice()
-		if err != nil {
+		if err := d.view.reset(); err != nil {
 			return err
 		}
 
-		d.ml = ca.MakeMetalLayer()
-		d.ml.SetDevice(d.device)
-		// https://developer.apple.com/documentation/quartzcore/cametallayer/1478155-pixelformat
-		//
-		// The pixel format for a Metal layer must be MTLPixelFormatBGRA8Unorm,
-		// MTLPixelFormatBGRA8Unorm_sRGB, MTLPixelFormatRGBA16Float, MTLPixelFormatBGRA10_XR, or
-		// MTLPixelFormatBGRA10_XR_sRGB.
-		d.ml.SetPixelFormat(mtl.PixelFormatBGRA8UNorm)
-		d.ml.SetMaximumDrawableCount(3)
-
 		replaces := map[string]string{
 			"{{.FilterNearest}}":      fmt.Sprintf("%d", graphics.FilterNearest),
 			"{{.FilterLinear}}":       fmt.Sprintf("%d", graphics.FilterLinear),
@@ -510,7 +496,7 @@ func (d *Driver) Reset() error {
 			src = strings.Replace(src, k, v, -1)
 		}
 
-		lib, err := d.device.MakeLibrary(src, mtl.CompileOptions{})
+		lib, err := d.view.getMTLDevice().MakeLibrary(src, mtl.CompileOptions{})
 		if err != nil {
 			return err
 		}
@@ -527,13 +513,13 @@ func (d *Driver) Reset() error {
 			VertexFunction:   vs,
 			FragmentFunction: fs,
 		}
-		rpld.ColorAttachments[0].PixelFormat = d.ml.PixelFormat()
+		rpld.ColorAttachments[0].PixelFormat = d.view.colorPixelFormat()
 		rpld.ColorAttachments[0].BlendingEnabled = true
 		rpld.ColorAttachments[0].DestinationAlphaBlendFactor = mtl.BlendFactorZero
 		rpld.ColorAttachments[0].DestinationRGBBlendFactor = mtl.BlendFactorZero
 		rpld.ColorAttachments[0].SourceAlphaBlendFactor = mtl.BlendFactorOne
 		rpld.ColorAttachments[0].SourceRGBBlendFactor = mtl.BlendFactorOne
-		rps, err := d.device.MakeRenderPipelineState(rpld)
+		rps, err := d.view.getMTLDevice().MakeRenderPipelineState(rpld)
 		if err != nil {
 			return err
 		}
@@ -588,7 +574,7 @@ func (d *Driver) Reset() error {
 						rpld.ColorAttachments[0].DestinationRGBBlendFactor = conv(dst)
 						rpld.ColorAttachments[0].SourceAlphaBlendFactor = conv(src)
 						rpld.ColorAttachments[0].SourceRGBBlendFactor = conv(src)
-						rps, err := d.device.MakeRenderPipelineState(rpld)
+						rps, err := d.view.getMTLDevice().MakeRenderPipelineState(rpld)
 						if err != nil {
 							return err
 						}
@@ -603,7 +589,7 @@ func (d *Driver) Reset() error {
 			}
 		}
 
-		d.cq = d.device.MakeCommandQueue()
+		d.cq = d.view.getMTLDevice().MakeCommandQueue()
 		return nil
 	}); err != nil {
 		return err
@@ -614,8 +600,7 @@ func (d *Driver) Reset() error {
 
 func (d *Driver) Draw(indexLen int, indexOffset int, mode graphics.CompositeMode, colorM *affine.ColorM, filter graphics.Filter, address graphics.Address) error {
 	if err := d.t.Call(func() error {
-		// NSView can be changed anytime (probably). Set this everyframe.
-		setView(d.window, d.ml)
+		d.view.update()
 
 		rpd := mtl.RenderPassDescriptor{}
 		if d.dst.screen {
@@ -628,9 +613,8 @@ func (d *Driver) Draw(indexLen int, indexOffset int, mode graphics.CompositeMode
 		var t mtl.Texture
 		if d.dst.screen {
 			if d.screenDrawable == (ca.MetalDrawable{}) {
-				drawable, err := d.ml.NextDrawable()
-				if err != nil {
-					// Drawable is nil. This can happen at the initial state. Let's wait and see.
+				drawable := d.view.drawable()
+				if drawable == (ca.MetalDrawable{}) {
 					return nil
 				}
 				d.screenDrawable = drawable
@@ -704,10 +688,7 @@ func (d *Driver) ResetSource() {
 }
 
 func (d *Driver) SetVsyncEnabled(enabled bool) {
-	// TODO: Now SetVsyncEnabled is called only from the main thread, and d.t.Run is not available since
-	// recursive function call via Run is forbidden.
-	// Fix this to use d.t.Run to avoid confusion.
-	d.ml.SetDisplaySyncEnabled(enabled)
+	d.view.setDisplaySyncEnabled(enabled)
 }
 
 func (d *Driver) VDirection() driver.VDirection {

internal/graphicsdriver/metal/view_ios.go

@@ -19,8 +19,44 @@ package metal
 
 import (
 	"github.com/hajimehoshi/ebiten/internal/graphicsdriver/metal/ca"
+	"github.com/hajimehoshi/ebiten/internal/graphicsdriver/metal/mtl"
 )
 
-func setView(window uintptr, layer ca.MetalLayer) {
-	// TODO: Implement this
+type view struct {
+}
+
+func (v *view) setWindow(window uintptr) {
+	panic("metal: setWindow cannot be called on iOS")
+}
+
+func (v *view) setDrawableSize(width, height int) {
+	// Do nothing
+}
+
+func (v *view) getMTLDevice() mtl.Device {
+	// TODO: Implement this
+	return mtl.Device{}
+}
+
+func (v *view) setDisplaySyncEnabled(enabled bool) {
+	// Do nothing
+}
+
+func (v *view) colorPixelFormat() mtl.PixelFormat {
+	// TODO: Implement this
+	return 0
+}
+
+func (v *view) reset() error {
+	// Do nothing
+	return nil
+}
+
+func (v *view) update() {
+	// Do nothing
+}
+
+func (v *view) drawable() ca.MetalDrawable {
+	// TODO: Implemnt this
+	return ca.MetalDrawable{}
 }

internal/graphicsdriver/metal/view_macos.go

@@ -0,0 +1,91 @@
+// Copyright 2019 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.
+
+// +build darwin
+// +build !ios
+
+package metal
+
+import (
+	"unsafe"
+
+	"github.com/hajimehoshi/ebiten/internal/graphicsdriver/metal/ca"
+	"github.com/hajimehoshi/ebiten/internal/graphicsdriver/metal/mtl"
+	"github.com/hajimehoshi/ebiten/internal/graphicsdriver/metal/ns"
+)
+
+type view struct {
+	window uintptr
+
+	device mtl.Device
+	ml     ca.MetalLayer
+}
+
+func (v *view) setWindow(window uintptr) {
+	v.window = window
+}
+
+func (v *view) setDrawableSize(width, height int) {
+	v.ml.SetDrawableSize(width, height)
+}
+
+func (v *view) getMTLDevice() mtl.Device {
+	return v.device
+}
+
+func (v *view) setDisplaySyncEnabled(enabled bool) {
+	// TODO: Now SetVsyncEnabled is called only from the main thread, and d.t.Run is not available since
+	// recursive function call via Run is forbidden.
+	// Fix this to use d.t.Run to avoid confusion.
+	v.ml.SetDisplaySyncEnabled(enabled)
+}
+
+func (v *view) colorPixelFormat() mtl.PixelFormat {
+	return v.ml.PixelFormat()
+}
+
+func (v *view) reset() error {
+	var err error
+	v.device, err = mtl.CreateSystemDefaultDevice()
+	if err != nil {
+		return err
+	}
+
+	v.ml = ca.MakeMetalLayer()
+	v.ml.SetDevice(v.device)
+	// https://developer.apple.com/documentation/quartzcore/cametallayer/1478155-pixelformat
+	//
+	// The pixel format for a Metal layer must be MTLPixelFormatBGRA8Unorm,
+	// MTLPixelFormatBGRA8Unorm_sRGB, MTLPixelFormatRGBA16Float, MTLPixelFormatBGRA10_XR, or
+	// MTLPixelFormatBGRA10_XR_sRGB.
+	v.ml.SetPixelFormat(mtl.PixelFormatBGRA8UNorm)
+	v.ml.SetMaximumDrawableCount(3)
+	return nil
+}
+
+func (v *view) update() {
+	// NSView can be changed anytime (probably). Set this everyframe.
+	cocoaWindow := ns.NewWindow(unsafe.Pointer(v.window))
+	cocoaWindow.ContentView().SetLayer(v.ml)
+	cocoaWindow.ContentView().SetWantsLayer(true)
+}
+
+func (v *view) drawable() ca.MetalDrawable {
+	d, err := v.ml.NextDrawable()
+	if err != nil {
+		// Drawable is nil. This can happen at the initial state. Let's wait and see.
+		return ca.MetalDrawable{}
+	}
+	return d
+}

internal/graphicsdriver/metal/view_notios.go

@@ -1,31 +0,0 @@
-// Copyright 2019 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.
-
-// +build darwin
-// +build !ios
-
-package metal
-
-import (
-	"unsafe"
-
-	"github.com/hajimehoshi/ebiten/internal/graphicsdriver/metal/ca"
-	"github.com/hajimehoshi/ebiten/internal/graphicsdriver/metal/ns"
-)
-
-func setView(window uintptr, layer ca.MetalLayer) {
-	cocoaWindow := ns.NewWindow(unsafe.Pointer(window))
-	cocoaWindow.ContentView().SetLayer(layer)
-	cocoaWindow.ContentView().SetWantsLayer(true)
-}