Introduce AutoBackendTexture into Skia-RenderEngine
Conceptually this is the same class as AutoBackendTextureRelease in
libhwui. We require this because:
* As with the equivalent class in libhwui, buffers are reused and
therefore their content is mutable, but SkImages are defined to be
immutable, so the workaround is to cache the backing texture instead.
* Color spaces associated with a buffer are not guaranteed to be
constant. The HWC is allowed to request a different color space for the
client target depending on the set of input layers. This means that
SkSurfaces need to be recreated when the color space changes.
Furthermore, since LinearEffects performs tone-mapping and wants
to sidestep Skia's built-in tone mapping process, this means that when
tone-mapping is enabled we lie about the color space of the input
buffers so that we don't do multiple tone-mapping passes. But this means
that SkImages need to be recreated for those scenarios too so that the
input content can be reinterpreted with a different color space.
Also, append additional trace points onto this CL to get a better handle
on RenderEngine perf.
Bug: 164223050
Test: On a Pixel 3, play HDR content on Youtube with PQ and HLG transfer
functions, and toggle full-screen GL composition on and off.
Change-Id: Ic53a422545b4fb563c7e75c73d978350d38181d5
diff --git a/libs/renderengine/skia/AutoBackendTexture.h b/libs/renderengine/skia/AutoBackendTexture.h
new file mode 100644
index 0000000..30f4b77
--- /dev/null
+++ b/libs/renderengine/skia/AutoBackendTexture.h
@@ -0,0 +1,111 @@
+/*
+ * Copyright 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <GrAHardwareBufferUtils.h>
+#include <GrDirectContext.h>
+#include <SkImage.h>
+#include <SkSurface.h>
+#include <sys/types.h>
+
+#include "android-base/macros.h"
+#include "ui/GraphicTypes.h"
+
+namespace android {
+namespace renderengine {
+namespace skia {
+
+/**
+ * AutoBackendTexture manages GPU image lifetime. It is a ref-counted object
+ * that keeps GPU resources alive until the last SkImage or SkSurface object using them is
+ * destroyed.
+ */
+class AutoBackendTexture {
+public:
+ // Local reference that supports RAII-style management of an AutoBackendTexture
+ // AutoBackendTexture by itself can't be managed in a similar fashion because
+ // of shared ownership with Skia objects, so we wrap it here instead.
+ class LocalRef {
+ public:
+ LocalRef() {}
+
+ ~LocalRef() {
+ // Destroying the texture is the same as setting it to null
+ setTexture(nullptr);
+ }
+
+ // Sets the texture to locally ref-track.
+ void setTexture(AutoBackendTexture* texture) {
+ if (mTexture != nullptr) {
+ mTexture->unref(true);
+ }
+
+ mTexture = texture;
+ if (mTexture != nullptr) {
+ mTexture->ref();
+ }
+ }
+
+ AutoBackendTexture* getTexture() const { return mTexture; }
+
+ DISALLOW_COPY_AND_ASSIGN(LocalRef);
+
+ private:
+ AutoBackendTexture* mTexture = nullptr;
+ };
+
+ // Creates a GrBackendTexture whose contents come from the provided buffer.
+ AutoBackendTexture(GrDirectContext* context, AHardwareBuffer* buffer, bool isRender);
+
+ void ref() { mUsageCount++; }
+
+ // releaseLocalResources is true if the underlying SkImage and SkSurface
+ // should be deleted from local tracking.
+ void unref(bool releaseLocalResources);
+
+ // Makes a new SkImage from the texture content.
+ // As SkImages are immutable but buffer content is not, we create
+ // a new SkImage every time.
+ sk_sp<SkImage> makeImage(ui::Dataspace dataspace, SkAlphaType alphaType,
+ GrDirectContext* context);
+
+ // Makes a new SkSurface from the texture content, if needed.
+ sk_sp<SkSurface> getOrCreateSurface(ui::Dataspace dataspace, GrDirectContext* context);
+
+private:
+ // The only way to invoke dtor is with unref, when mUsageCount is 0.
+ ~AutoBackendTexture() {}
+
+ GrBackendTexture mBackendTexture;
+ GrAHardwareBufferUtils::DeleteImageProc mDeleteProc;
+ GrAHardwareBufferUtils::UpdateImageProc mUpdateProc;
+ GrAHardwareBufferUtils::TexImageCtx mImageCtx;
+
+ static void releaseSurfaceProc(SkSurface::ReleaseContext releaseContext);
+ static void releaseImageProc(SkImage::ReleaseContext releaseContext);
+
+ int mUsageCount = 0;
+
+ sk_sp<SkImage> mImage = nullptr;
+ sk_sp<SkSurface> mSurface = nullptr;
+ ui::Dataspace mDataspace = ui::Dataspace::UNKNOWN;
+ SkColorType mColorType = kUnknown_SkColorType;
+};
+
+} // namespace skia
+} // namespace renderengine
+} // namespace android