app/internal/wm: rename confusing app/internal/window

Package wm (for "window manager") is a better fit for the package, and
distinguishes it from the low-level package windows for the Windows API.

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

app/internal/wm/d3d11_windows.go

@@ -0,0 +1,140 @@
+// SPDX-License-Identifier: Unlicense OR MIT
+
+package wm
+
+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
+	depthView     *d3d11.DepthStencilView
+	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) 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) MakeCurrent() error {
+	_, width, height := c.win.HWND()
+	if c.renderTarget != nil && width == c.width && height == c.height {
+		c.ctx.OMSetRenderTargets(c.renderTarget, c.depthView)
+		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
+
+	desc, err := c.swchain.GetDesc()
+	if err != nil {
+		return err
+	}
+	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
+	}
+	depthView, err := d3d11.CreateDepthView(c.dev, int(desc.BufferDesc.Width), int(desc.BufferDesc.Height), 24)
+	if err != nil {
+		d3d11.IUnknownRelease(unsafe.Pointer(renderTarget), renderTarget.Vtbl.Release)
+		return err
+	}
+	c.renderTarget = renderTarget
+	c.depthView = depthView
+
+	c.ctx.OMSetRenderTargets(c.renderTarget, c.depthView)
+	return nil
+}
+
+func (c *d3d11Context) Lock() {}
+
+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{}
+}
+
+func (c *d3d11Context) releaseFBO() {
+	if c.depthView != nil {
+		d3d11.IUnknownRelease(unsafe.Pointer(c.depthView), c.depthView.Vtbl.Release)
+		c.depthView = nil
+	}
+	if c.renderTarget != nil {
+		d3d11.IUnknownRelease(unsafe.Pointer(c.renderTarget), c.renderTarget.Vtbl.Release)
+		c.renderTarget = nil
+	}
+}