Move instanced index buffer creation to flush time

include/gpu/GrResourceKey.h

 
 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrResourceKey_DEFINED
 #define GrResourceKey_DEFINED
 
 #include "GrTypes.h"
+#include "SkOnce.h"
 #include "SkTemplates.h"
 
 uint32_t GrResourceKeyHash(const uint32_t* data, size_t size);
 
 /**
  * Base class for all GrGpuResource cache keys. There are two types of cache keys. Refer to the
  * comments for each key type below.
  */
 class GrResourceKey {
 public:
@@ skipping 236 matching lines @@
         }
 
     private:
         static int Data32CntForInnerKey(const GrUniqueKey& innerKey) {
             // key data + domain
             return SkToInt((innerKey.dataSize() >> 2) + 1);
         }
     };
 };
 
+/**
+ * It is common to need a frequently reused GrUniqueKey where the only requirement is that the key
+ * is unique. These macros create such a key in a thread safe manner so the key can be truly global
+ * and only constructed once.
+ */
+
+/** Place outside of function/class definitions. */
+#define GR_DECLARE_STATIC_UNIQUE_KEY(name) SK_DECLARE_STATIC_ONCE(name##_once)
+
+/** Place inside function where the key is used. */
+#define GR_DEFINE_STATIC_UNIQUE_KEY(name)                           \
+    static GrUniqueKey name;                                        \
+    SkOnce(&name##_once, gr_init_static_unique_key_once, &name)
+
+static inline void gr_init_static_unique_key_once(GrUniqueKey* key) {
+    GrUniqueKey::Builder builder(key, GrUniqueKey::GenerateDomain(), 0);
+}
+
 // The cache listens for these messages to purge junk resources proactively.
 class GrUniqueKeyInvalidatedMessage {
 public:
     explicit GrUniqueKeyInvalidatedMessage(const GrUniqueKey& key) : fKey(key) {}
 
     GrUniqueKeyInvalidatedMessage(const GrUniqueKeyInvalidatedMessage& that) : fKey(that.fKey) {}
 
     GrUniqueKeyInvalidatedMessage& operator=(const GrUniqueKeyInvalidatedMessage& that) {
         fKey = that.fKey;
         return *this;
     }
 
     const GrUniqueKey& key() const { return fKey; }
 
 private:
     GrUniqueKey fKey;
 };
 #endif