SkImage::isValid

Lets clients know if an image is drawable to a particular GrContext
(or to CPU). Checks for abandoned GrContexts beneath GPU backed
images, as well as context mis-match.

Bug: skia:
Change-Id: Ibe88c7ce8091f965c14f6023a3597be4b70c3f99
Reviewed-on: https://skia-review.googlesource.com/15801
Commit-Queue: Brian Osman <brianosman@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/include/core/SkImageGenerator.h b/include/core/SkImageGenerator.h
index a899c44d92..348f281965 100644
--- a/include/core/SkImageGenerator.h
+++ b/include/core/SkImageGenerator.h
@@ -51,6 +51,14 @@ public:
     const SkImageInfo& getInfo() const { return fInfo; }
 
     /**
+     *  Can this generator be used to produce images that will be drawable to the specified context
+     *  (or to CPU, if context is nullptr)?
+     */
+    bool isValid(GrContext* context) const {
+        return this->onIsValid(context);
+    }
+
+    /**
      *  Decode into the given pixels, a block of memory of size at
      *  least (info.fHeight - 1) * rowBytes + (info.fWidth *
      *  bytesPerPixel)
@@ -166,6 +174,8 @@ protected:
     virtual bool onGetPixels(const SkImageInfo& info, void* pixels, size_t rowBytes,
                              SkPMColor ctable[], int* ctableCount);
 
+    virtual bool onIsValid(GrContext*) const;
+
     virtual bool onQueryYUV8(SkYUVSizeInfo*, SkYUVColorSpace*) const {
         return false;
     }