| Index: third_party/WebKit/Source/platform/graphics/skia/SkiaUtils.h
|
| diff --git a/third_party/WebKit/Source/platform/graphics/skia/SkiaUtils.h b/third_party/WebKit/Source/platform/graphics/skia/SkiaUtils.h
|
| index 3c3781bc87a3a63ba77324fec711ceb68d8e1fdb..08aac8948be7dcbbb24b211d617d9ee872bbe66d 100644
|
| --- a/third_party/WebKit/Source/platform/graphics/skia/SkiaUtils.h
|
| +++ b/third_party/WebKit/Source/platform/graphics/skia/SkiaUtils.h
|
| @@ -38,6 +38,7 @@
|
| #include "platform/graphics/Image.h"
|
| #include "platform/transforms/AffineTransform.h"
|
| #include "third_party/skia/include/core/SkCanvas.h"
|
| +#include "third_party/skia/include/core/SkRefCnt.h"
|
| #include "wtf/MathExtras.h"
|
|
|
| namespace blink {
|
| @@ -126,6 +127,84 @@ inline SkCanvas::SrcRectConstraint WebCoreClampingModeToSkiaRectConstraint(Image
|
| : SkCanvas::kFast_SrcRectConstraint;
|
| }
|
|
|
| +
|
| } // namespace blink
|
|
|
| +namespace WTF {
|
| +
|
| +// Skia's smart pointer APIs are preferable over their legacy raw pointer counterparts.
|
| +// The following helpers ensure interoperability between Skia's SkRefCnt wrapper sk_sp<T> and
|
| +// Blink's RefPtr<T>/PassRefPtr<T>.
|
| +//
|
| +// - adoptRef(sk_sp<T>): adopts an sk_sp rvalue into a PassRefPtr (to be used when
|
| +// transferring ownership from Skia to Blink).
|
| +// - adoptSkSp(PassRefPtr<T>): adopts a PassRefPtr rvalue into a sk_sp (to be used when
|
| +// transferring ownership from Blink to Skia).
|
| +//
|
| +// General guidelines
|
| +//
|
| +// When receiving ref counted objects from Skia:
|
| +//
|
| +// 1) use sk_sp-based Skia factories if available (e.g. SkShader::MakeFoo() instead of
|
| +// SkShader::CreateFoo())
|
| +//
|
| +// 2) use sk_sp<T> locals for temporary objects (to be immediately transferred back to Skia)
|
| +//
|
| +// 3) use RefPtr<T>/PassRefPtr<T> for objects to be retained in Blink, use
|
| +// adoptRef(sk_sp<T>) to convert
|
| +//
|
| +// When passing ref counted objects to Skia:
|
| +//
|
| +// 1) use sk_sk-based Skia APIs when available (e.g. SkPaint::setShader(sk_sp<SkShader>)
|
| +// instead of SkPaint::setShader(SkShader*))
|
| +//
|
| +// 2) if the object ownership is being passed to Skia, use std::move(sk_sp<T>) or
|
| +// adoptSkSp(PassRefPtr<T>) to transfer without refcount churn
|
| +//
|
| +// 3) if the object ownership is shared with Skia (Blink retains a reference), use
|
| +// sk_ref_sp(RefPtr<T>::get())
|
| +//
|
| +// Example (creating a SkShader and setting it on SkPaint):
|
| +//
|
| +// a) legacy/old style
|
| +//
|
| +// RefPtr<SkShader> shader = adoptRef(SkShader::CreateFoo(...));
|
| +// paint.setShader(shader.get());
|
| +//
|
| +// (Note: the legacy approach introduces refcount churn as Skia grabs a ref while Blink is
|
| +// temporarily holding on to its own)
|
| +//
|
| +// b) new style, ownership transferred
|
| +//
|
| +// // using Skia smart pointer locals
|
| +// sk_sp<SkShader> shader = SkShader::MakeFoo(...);
|
| +// paint.setShader(std::move(shader));
|
| +//
|
| +// // using Blink smart pointer locals
|
| +// RefPtr<SkShader> shader = adoptRef(SkShader::MakeFoo(...));
|
| +// paint.setShader(adoptSkSp(shader.release());
|
| +//
|
| +// // using no locals
|
| +// paint.setShader(SkShader::MakeFoo(...));
|
| +//
|
| +// c) new style, shared ownership
|
| +//
|
| +// RefPtr<SkShader> m_shader = adoptRef(SkShader::MakeFoo(...));
|
| +// paint.setShader(adoptSkSp<SkShader>(m_shader));
|
| +//
|
| +template <typename T> PassRefPtr<T> adoptRef(sk_sp<T> sp)
|
| +{
|
| + return adoptRef(sp.release());
|
| +}
|
| +
|
| +template <typename T> sk_sp<T> adoptSkSp(PassRefPtr<T> ref)
|
| +{
|
| + return sk_sp<T>(ref.leakRef());
|
| +}
|
| +
|
| +} // namespace WTF
|
| +
|
| +using WTF::adoptRef;
|
| +using WTF::adoptSkSp;
|
| +
|
| #endif // SkiaUtils_h
|
|
|