app,app/internal/wm: introduce app.Window.Run and use it internally

app.Window implements a method for safely running functions against the
underlying native window through the driverFuncs channel. However, the
functions still run in a different goroutine than the one driving the
native event loop, which forces the implementations in package wm to do
complicated synchronization.

A previous change added a mechanism to run functions in the native event
loop thread. The macOS port needed this functionality, but with some
care it can be generalized. That's what this change does through the
new Run method.

The advantage is that the thread switch dance is now confined to
app.Window, with the help of a generic wm.Driver.Wakeup method. All
other Driver methods can then assume they run on their event loop
threads.

Run is exported because it is also needed for programs that use
Windows configured with CustomRenderer to control their own rendering.

Signed-off-by: Elias Naur <mail@eliasnaur.com>
This commit is contained in:
Elias Naur
2021-05-18 12:34:58 +01:00
parent c914935169
commit 8611894b4b
14 changed files with 283 additions and 380 deletions
+33 -66
View File
@@ -179,9 +179,7 @@ type window struct {
dead bool
lastFrameCallback *C.struct_wl_callback
mu sync.Mutex
animating bool
opts *Options
needAck bool
// The most recent configure serial waiting to be ack'ed.
serial C.uint32_t
@@ -189,10 +187,8 @@ type window struct {
height int
newScale bool
scale int
// readClipboard tracks whether a ClipboardEvent is requested.
readClipboard bool
// writeClipboard is set whenever a clipboard write is requested.
writeClipboard *string
wakeups chan struct{}
}
type poller struct {
@@ -319,6 +315,7 @@ func (d *wlDisplay) createNativeWindow(opts *Options) (*window, error) {
newScale: scale != 1,
ppdp: ppdp,
ppsp: ppdp,
wakeups: make(chan struct{}, 1),
}
w.surf = C.wl_compositor_create_surface(d.compositor)
if w.surf == nil {
@@ -473,10 +470,8 @@ func gio_onSeatName(data unsafe.Pointer, seat *C.struct_wl_seat, name *C.char) {
//export gio_onXdgSurfaceConfigure
func gio_onXdgSurfaceConfigure(data unsafe.Pointer, wmSurf *C.struct_xdg_surface, serial C.uint32_t) {
w := callbackLoad(data).(*window)
w.mu.Lock()
w.serial = serial
w.needAck = true
w.mu.Unlock()
w.setStage(system.StageRunning)
w.draw(true)
}
@@ -491,8 +486,6 @@ func gio_onToplevelClose(data unsafe.Pointer, topLvl *C.struct_xdg_toplevel) {
func gio_onToplevelConfigure(data unsafe.Pointer, topLvl *C.struct_xdg_toplevel, width, height C.int32_t, states *C.struct_wl_array) {
w := callbackLoad(data).(*window)
if width != 0 && height != 0 {
w.mu.Lock()
defer w.mu.Unlock()
w.width = int(width)
w.height = int(height)
w.updateOpaqueRegion()
@@ -868,8 +861,6 @@ func (w *window) flushFling() {
invDist := 1 / vel
w.fling.dir.X = estx.Velocity * invDist
w.fling.dir.Y = esty.Velocity * invDist
// Wake up the window loop.
w.disp.wakeup()
}
//export gio_onPointerAxisSource
@@ -897,24 +888,26 @@ func gio_onPointerAxisDiscrete(data unsafe.Pointer, p *C.struct_wl_pointer, axis
}
func (w *window) ReadClipboard() {
w.mu.Lock()
w.readClipboard = true
w.mu.Unlock()
w.disp.wakeup()
r, err := w.disp.readClipboard()
// Send empty responses on unavailable clipboards or errors.
if r == nil || err != nil {
w.w.Event(clipboard.Event{})
return
}
// Don't let slow clipboard transfers block event loop.
go func() {
defer r.Close()
data, _ := ioutil.ReadAll(r)
w.w.Event(clipboard.Event{Text: string(data)})
}()
}
func (w *window) WriteClipboard(s string) {
w.mu.Lock()
w.writeClipboard = &s
w.mu.Unlock()
w.disp.wakeup()
w.disp.writeClipboard([]byte(s))
}
func (w *window) Option(opts *Options) {
w.mu.Lock()
w.opts = opts
w.mu.Unlock()
w.disp.wakeup()
w.setOptions(opts)
}
func (w *window) setOptions(opts *Options) {
@@ -1138,48 +1131,21 @@ func (w *window) loop() error {
if err := w.disp.dispatch(&p); err != nil {
return err
}
select {
case <-w.wakeups:
w.w.Event(WakeupEvent{})
default:
}
if w.dead {
w.w.Event(system.DestroyEvent{})
break
}
w.process()
// pass false to skip unnecessary drawing.
w.draw(false)
}
return nil
}
func (w *window) process() {
w.mu.Lock()
readClipboard := w.readClipboard
writeClipboard := w.writeClipboard
opts := w.opts
w.readClipboard = false
w.writeClipboard = nil
w.opts = nil
w.mu.Unlock()
if readClipboard {
r, err := w.disp.readClipboard()
// Send empty responses on unavailable clipboards or errors.
if r == nil || err != nil {
w.w.Event(clipboard.Event{})
return
}
// Don't let slow clipboard transfers block event loop.
go func() {
defer r.Close()
data, _ := ioutil.ReadAll(r)
w.w.Event(clipboard.Event{Text: string(data)})
}()
}
if writeClipboard != nil {
w.disp.writeClipboard([]byte(*writeClipboard))
}
if opts != nil {
w.setOptions(opts)
}
// pass false to skip unnecessary drawing.
w.draw(false)
}
func (d *wlDisplay) dispatch(p *poller) error {
dispfd := C.wl_display_get_fd(d.disp)
// Poll for events and notifications.
@@ -1222,13 +1188,18 @@ func (d *wlDisplay) dispatch(p *poller) error {
return nil
}
func (w *window) SetAnimating(anim bool) {
w.mu.Lock()
w.animating = anim
w.mu.Unlock()
func (w *window) Wakeup() {
select {
case w.wakeups <- struct{}{}:
default:
}
w.disp.wakeup()
}
func (w *window) SetAnimating(anim bool) {
w.animating = anim
}
// Wakeup wakes up the event loop through the notification pipe.
func (d *wlDisplay) wakeup() {
oneByte := make([]byte, 1)
@@ -1415,12 +1386,10 @@ func (w *window) updateOutputs() {
}
}
}
w.mu.Lock()
if found && scale != w.scale {
w.scale = scale
w.newScale = true
}
w.mu.Unlock()
if !found {
w.setStage(system.StagePaused)
} else {
@@ -1439,10 +1408,8 @@ func (w *window) config() (int, int, unit.Metric) {
func (w *window) draw(sync bool) {
w.flushScroll()
w.mu.Lock()
anim := w.animating || w.fling.anim.Active()
dead := w.dead
w.mu.Unlock()
if dead || (!anim && !sync) {
return
}