gpu/backend: move backend interface types to a separate package

Signed-off-by: Elias Naur <mail@eliasnaur.com>

app/internal/window/gl_ios.go

@@ -17,7 +17,7 @@ import (
 	"fmt"
 
 	"gioui.org/app/internal/glimpl"
-	"gioui.org/gpu"
+	"gioui.org/gpu/backend"
 	"gioui.org/gpu/gl"
 )
 
@@ -51,7 +51,7 @@ func newContext(w *window) (*context, error) {
 	return c, nil
 }
 
-func (c *context) Backend() (gpu.Backend, error) {
+func (c *context) Backend() (backend.Device, error) {
 	return gl.NewBackend(c.c)
 }
 

app/internal/window/gl_js.go

@@ -8,7 +8,7 @@ import (
 
 	"gioui.org/app/internal/glimpl"
 	"gioui.org/app/internal/srgb"
-	"gioui.org/gpu"
+	"gioui.org/gpu/backend"
 	"gioui.org/gpu/gl"
 )
 
@@ -47,7 +47,7 @@ func newContext(w *window) (*context, error) {
 	return c, nil
 }
 
-func (c *context) Backend() (gpu.Backend, error) {
+func (c *context) Backend() (backend.Device, error) {
 	return gl.NewBackend(c.f)
 }
 

app/internal/window/gl_macos.go

@@ -6,7 +6,7 @@ package window
 
 import (
 	"gioui.org/app/internal/glimpl"
-	"gioui.org/gpu"
+	"gioui.org/gpu/backend"
 	"gioui.org/gpu/gl"
 )
 
@@ -42,7 +42,7 @@ func newContext(w *window) (*context, error) {
 	return c, nil
 }
 
-func (c *context) Backend() (gpu.Backend, error) {
+func (c *context) Backend() (backend.Device, error) {
 	return gl.NewBackend(c.c)
 }
 

app/internal/window/window.go

@@ -9,7 +9,7 @@ import (
 	"math"
 	"time"
 
-	"gioui.org/gpu"
+	"gioui.org/gpu/backend"
 	"gioui.org/io/event"
 	"gioui.org/io/system"
 	"gioui.org/unit"
@@ -32,7 +32,7 @@ type Callbacks interface {
 }
 
 type Context interface {
-	Backend() (gpu.Backend, error)
+	Backend() (backend.Device, error)
 	Present() error
 	MakeCurrent() error
 	Release()