commit d63638bb7be75786908c5e87b9c9165cbe95dcfb
author Brian Salomon <bsalomon@google.com> Fri Mar 05 14:00:07 2021 -0500
committer Skia Commit-Bot <skia-commit-bot@chromium.org> Fri Mar 05 19:50:05 2021 +0000
tree d88ac71fecba2e2cbdcd2b881469a2be6ea4806c
parent cad44bcdd288da81060b5ba6bd5ce6833b7e9146

Copy on write for wrapped backend texture surfaces.

Makes SkImage_Gpu backed by two proxies, an original and a copy. The
image uses the original until a new render task is bound to it at which
point further uses of the image will use the copy. If the image is ever
used off a GrDirectContext we fall over to the copy. If the copy is
never used and never can be used by the next flush then the render
task that populates it is marked "skipped" and we don't perform the
copy.

Bug: skia:11208

Change-Id: Id255f4a733acc608c8a53c1a5633207aeafc404b
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/366282
Commit-Queue: Brian Salomon <bsalomon@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>

src/gpu/GrDrawingManager.cpp

diff --git a/src/gpu/GrDrawingManager.cpp b/src/gpu/GrDrawingManager.cpp
index cc4f761..628d0fe 100644
--- a/src/gpu/GrDrawingManager.cpp
+++ b/src/gpu/GrDrawingManager.cpp
@@ -798,11 +798,11 @@
     SkDEBUGCODE(this->validate());
 }
 
-bool GrDrawingManager::newCopyRenderTask(sk_sp<GrSurfaceProxy> src,
-                                         SkIRect srcRect,
-                                         sk_sp<GrSurfaceProxy> dst,
-                                         SkIPoint dstPoint,
-                                         GrSurfaceOrigin origin) {
+sk_sp<GrRenderTask> GrDrawingManager::newCopyRenderTask(sk_sp<GrSurfaceProxy> src,
+                                                        SkIRect srcRect,
+                                                        sk_sp<GrSurfaceProxy> dst,
+                                                        SkIPoint dstPoint,
+                                                        GrSurfaceOrigin origin) {
     SkDEBUGCODE(this->validate());
     SkASSERT(fContext);
 
@@ -813,21 +813,23 @@
     // task, then fail to make a copy task, the next active ops task may target the same proxy. This
     // will trip an assert related to unnecessary ops task splitting.
     if (src->framebufferOnly()) {
-        return false;
+        return nullptr;
     }
 
     this->closeActiveOpsTask();
 
-    GrRenderTask* task = this->appendTask(GrCopyRenderTask::Make(this,
-                                                                 src,
-                                                                 srcRect,
-                                                                 std::move(dst),
-                                                                 dstPoint,
-                                                                 origin));
+    sk_sp<GrRenderTask> task = GrCopyRenderTask::Make(this,
+                                                      src,
+                                                      srcRect,
+                                                      std::move(dst),
+                                                      dstPoint,
+                                                      origin);
     if (!task) {
-        return false;
+        return nullptr;
     }
 
+    this->appendTask(task);
+
     const GrCaps& caps = *fContext->priv().caps();
     // We always say GrMipmapped::kNo here since we are always just copying from the base layer to
     // another base layer. We don't need to make sure the whole mip map chain is valid.
@@ -838,7 +840,7 @@
     // shouldn't be an active one.
     SkASSERT(!fActiveOpsTask);
     SkDEBUGCODE(this->validate());
-    return true;
+    return task;
 }
 
 bool GrDrawingManager::newWritePixelsTask(sk_sp<GrSurfaceProxy> dst,