restorable: Defer operations between the end and the beginning of frames

Updates #913
This commit is contained in:
Hajime Hoshi 2019-08-12 14:49:08 +09:00
parent de49bbab12
commit 1a2a0aeb76
2 changed files with 96 additions and 2 deletions

View File

@ -122,6 +122,8 @@ func init() {
//
// Note that Dispose is not called automatically.
func NewImage(width, height int) *Image {
// As this should not affect the information for restoring, this doesn't have to be deferred.
i := &Image{
image: graphicscommand.NewImage(width, height),
}
@ -173,6 +175,8 @@ func (i *Image) MakeVolatile() {
//
// Note that Dispose is not called automatically.
func NewScreenFramebufferImage(width, height int) *Image {
// As this should not affect the information for restoring, this doesn't have to be deferred.
i := &Image{
image: graphicscommand.NewScreenFramebufferImage(width, height),
screen: true,
@ -183,6 +187,18 @@ func NewScreenFramebufferImage(width, height int) *Image {
}
func (i *Image) Clear() {
select {
case theImages.deferCh <- struct{}{}:
break
default:
theImages.deferUntilBeginFrame(i.Clear)
return
}
defer func() {
<-theImages.deferCh
}()
theImages.makeStaleIfDependingOn(i)
i.clear()
}
@ -293,6 +309,20 @@ func (i *Image) ClearPixels(x, y, width, height int) {
//
// ReplacePixels for a part is forbidden if the image is rendered with DrawTriangles or Fill.
func (i *Image) ReplacePixels(pixels []byte, x, y, width, height int) {
select {
case theImages.deferCh <- struct{}{}:
break
default:
theImages.deferUntilBeginFrame(func() {
i.ReplacePixels(pixels, x, y, width, height)
})
return
}
defer func() {
<-theImages.deferCh
}()
w, h := i.image.Size()
if width <= 0 || height <= 0 {
panic("restorable: width/height must be positive")
@ -346,6 +376,20 @@ func (i *Image) ReplacePixels(pixels []byte, x, y, width, height int) {
// DrawTriangles draws a given image img to the image.
func (i *Image) DrawTriangles(img *Image, vertices []float32, indices []uint16, colorm *affine.ColorM, mode driver.CompositeMode, filter driver.Filter, address driver.Address) {
select {
case theImages.deferCh <- struct{}{}:
break
default:
theImages.deferUntilBeginFrame(func() {
i.DrawTriangles(img, vertices, indices, colorm, mode, filter, address)
})
return
}
defer func() {
<-theImages.deferCh
}()
if i.priority {
panic("restorable: DrawTriangles cannot be called on a priority image")
}
@ -400,6 +444,8 @@ func (i *Image) readPixelsFromGPUIfNeeded() {
//
// Note that this must not be called until context is available.
func (i *Image) At(x, y int) (byte, byte, byte, byte) {
// As this should not affect the information for restoring, this doesn't have to be deferred.
w, h := i.image.Size()
if x < 0 || y < 0 || w <= x || h <= y {
return 0, 0, 0, 0
@ -528,7 +574,6 @@ func (i *Image) restore() error {
// After disposing, calling the function of the image causes unexpected results.
func (i *Image) Dispose() {
theImages.remove(i)
i.image.Dispose()
i.image = nil
i.basePixels = Pixels{}

View File

@ -16,6 +16,7 @@ package restorable
import (
"path/filepath"
"sync"
"github.com/hajimehoshi/ebiten/internal/graphicscommand"
)
@ -40,11 +41,18 @@ func EnableRestoringForTesting() {
type images struct {
images map[*Image]struct{}
lastTarget *Image
deferred []func()
mDeferred sync.Mutex
deferCh chan struct{}
once sync.Once
}
// theImages represents the images for the current process.
var theImages = &images{
images: map[*Image]struct{}{},
deferCh: make(chan struct{}, 1),
}
// ResolveStaleImages flushes the queued draw commands and resolves
@ -52,6 +60,11 @@ var theImages = &images{
//
// ResolveStaleImages is intended to be called at the end of a frame.
func ResolveStaleImages() {
defer func() {
// Until the begin o the frame (by RestoreIfNeeded, any operations are deferred.
theImages.deferCh <- struct{}{}
}()
graphicscommand.FlushCommands()
if !needsRestoring() {
return
@ -63,6 +76,25 @@ func ResolveStaleImages() {
//
// Restoring means to make all *graphicscommand.Image objects have their textures and framebuffers.
func RestoreIfNeeded() error {
// Unlock except for the first time.
//
// In each frame, restoring images and resolving images happen respectively:
//
// [Restore -> Resolve] -> [Restore -> Resolve] -> ...
//
// Between each frame, any image operations are not permitted, or stale images would remain when restoring
// (#913).
firsttime := false
theImages.once.Do(func() {
firsttime = true
})
if !firsttime {
<-theImages.deferCh
}
// Deferred functions should be resolved after restoring.
defer theImages.resolveDeferred()
if !needsRestoring() {
return nil
}
@ -113,9 +145,26 @@ func (i *images) remove(img *Image) {
delete(i.images, img)
}
func (i *images) deferUntilBeginFrame(f func()) {
i.mDeferred.Lock()
defer i.mDeferred.Unlock()
i.deferred = append(i.deferred, f)
}
func (i *images) resolveDeferred() {
i.mDeferred.Lock()
defer i.mDeferred.Unlock()
for _, f := range i.deferred {
f()
}
i.deferred = nil
}
// resolveStaleImages resolves stale images.
func (i *images) resolveStaleImages() {
i.lastTarget = nil
i.resolveDeferred()
for img := range i.images {
img.resolveStale()
}