app: merge app/internal/wm into package app

The app and app/internal/wm packages are tightly coupled, requiring
quite a bit of forwarding types, values and constants from the internal
package to export it. Further, no other package imports package wm.

This change merges the two packages.

While here, drop the pre-Go 1.14 SIGPIPE workaround.

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

app/d3d11_windows.go

@@ -0,0 +1,135 @@
+// SPDX-License-Identifier: Unlicense OR MIT
+
+package app
+
+import (
+	"fmt"
+	"unsafe"
+
+	"gioui.org/gpu"
+	"gioui.org/internal/d3d11"
+)
+
+type d3d11Context struct {
+	win *window
+	dev *d3d11.Device
+	ctx *d3d11.DeviceContext
+
+	swchain       *d3d11.IDXGISwapChain
+	renderTarget  *d3d11.RenderTargetView
+	width, height int
+}
+
+const debug = false
+
+func init() {
+	drivers = append(drivers, gpuAPI{
+		priority: 1,
+		initializer: func(w *window) (context, error) {
+			hwnd, _, _ := w.HWND()
+			var flags uint32
+			if debug {
+				flags |= d3d11.CREATE_DEVICE_DEBUG
+			}
+			dev, ctx, _, err := d3d11.CreateDevice(
+				d3d11.DRIVER_TYPE_HARDWARE,
+				flags,
+			)
+			if err != nil {
+				return nil, fmt.Errorf("NewContext: %v", err)
+			}
+			swchain, err := d3d11.CreateSwapChain(dev, hwnd)
+			if err != nil {
+				d3d11.IUnknownRelease(unsafe.Pointer(ctx), ctx.Vtbl.Release)
+				d3d11.IUnknownRelease(unsafe.Pointer(dev), dev.Vtbl.Release)
+				return nil, err
+			}
+			return &d3d11Context{win: w, dev: dev, ctx: ctx, swchain: swchain}, nil
+		},
+	})
+}
+
+func (c *d3d11Context) API() gpu.API {
+	return gpu.Direct3D11{Device: unsafe.Pointer(c.dev)}
+}
+
+func (c *d3d11Context) RenderTarget() gpu.RenderTarget {
+	return gpu.Direct3D11RenderTarget{
+		RenderTarget: unsafe.Pointer(c.renderTarget),
+	}
+}
+
+func (c *d3d11Context) Present() error {
+	err := c.swchain.Present(1, 0)
+	if err == nil {
+		return nil
+	}
+	if err, ok := err.(d3d11.ErrorCode); ok {
+		switch err.Code {
+		case d3d11.DXGI_STATUS_OCCLUDED:
+			// Ignore
+			return nil
+		case d3d11.DXGI_ERROR_DEVICE_RESET, d3d11.DXGI_ERROR_DEVICE_REMOVED, d3d11.D3DDDIERR_DEVICEREMOVED:
+			return errDeviceLost
+		}
+	}
+	return err
+}
+
+func (c *d3d11Context) Refresh() error {
+	var width, height int
+	_, width, height = c.win.HWND()
+	if c.renderTarget != nil && width == c.width && height == c.height {
+		return nil
+	}
+	c.releaseFBO()
+	if err := c.swchain.ResizeBuffers(0, 0, 0, d3d11.DXGI_FORMAT_UNKNOWN, 0); err != nil {
+		return err
+	}
+	c.width = width
+	c.height = height
+
+	backBuffer, err := c.swchain.GetBuffer(0, &d3d11.IID_Texture2D)
+	if err != nil {
+		return err
+	}
+	texture := (*d3d11.Resource)(unsafe.Pointer(backBuffer))
+	renderTarget, err := c.dev.CreateRenderTargetView(texture)
+	d3d11.IUnknownRelease(unsafe.Pointer(backBuffer), backBuffer.Vtbl.Release)
+	if err != nil {
+		return err
+	}
+	c.renderTarget = renderTarget
+	return nil
+}
+
+func (c *d3d11Context) Lock() error {
+	c.ctx.OMSetRenderTargets(c.renderTarget, nil)
+	return nil
+}
+
+func (c *d3d11Context) Unlock() {}
+
+func (c *d3d11Context) Release() {
+	c.releaseFBO()
+	if c.swchain != nil {
+		d3d11.IUnknownRelease(unsafe.Pointer(c.swchain), c.swchain.Vtbl.Release)
+	}
+	if c.ctx != nil {
+		d3d11.IUnknownRelease(unsafe.Pointer(c.ctx), c.ctx.Vtbl.Release)
+	}
+	if c.dev != nil {
+		d3d11.IUnknownRelease(unsafe.Pointer(c.dev), c.dev.Vtbl.Release)
+	}
+	*c = d3d11Context{}
+	if debug {
+		d3d11.ReportLiveObjects()
+	}
+}
+
+func (c *d3d11Context) releaseFBO() {
+	if c.renderTarget != nil {
+		d3d11.IUnknownRelease(unsafe.Pointer(c.renderTarget), c.renderTarget.Vtbl.Release)
+		c.renderTarget = nil
+	}
+}