Reopened: Caching the result of readPixelsSupported

src/gpu/gl/GrGLCaps.h

Index: src/gpu/gl/GrGLCaps.h
diff --git a/src/gpu/gl/GrGLCaps.h b/src/gpu/gl/GrGLCaps.h
index ccf04fd7ba5a3d668ef5d2671d0defc5af6ea6b6..a316af668a12b923c2e71a561ecc553223a61324 100644
--- a/src/gpu/gl/GrGLCaps.h
+++ b/src/gpu/gl/GrGLCaps.h
@@ -11,8 +11,9 @@
 
 #include "GrDrawTargetCaps.h"
 #include "GrGLStencilBuffer.h"
+#include "SkTHashCache.h"
+#include "GrTHashTable.h"

[mtklein, 2014/07/11 17:08:08]

Do you still need this?

[Rémi Piotaix, 2014/07/11 17:45:01]

This one is not needed: "GrTHashTable.h"

Deleted.

 #include "SkTArray.h"
-#include "SkTDArray.h"
 
 class GrGLContextInfo;
 
@@ -253,7 +254,8 @@ public:
     /// Does ReadPixels support the provided format/type combo?
     bool readPixelsSupported(const GrGLInterface* intf,
                              GrGLenum format,
-                             GrGLenum type) const;
+                             GrGLenum type,
+                             GrGLenum currFboFormat) const;
 
     bool isCoreProfile() const { return fIsCoreProfile; }
 
@@ -324,6 +326,10 @@ private:
     void initConfigRenderableTable(const GrGLContextInfo&);
     void initConfigTexturableTable(const GrGLContextInfo&, const GrGLInterface*);
 
+    bool doReadPixelsSupported(const GrGLInterface* intf,
+                                   GrGLenum format,
+                                   GrGLenum type) const;
+
     // tracks configs that have been verified to pass the FBO completeness when
     // used as a color attachment
     VerifiedColorConfigs fVerifiedColorConfigs;
@@ -364,6 +370,55 @@ private:
     bool fFullClearIsFree : 1;
     bool fDropsTileOnZeroDivide : 1;
 
+    class ReadPixelsSupportedFormats {
+    public:
+        struct Key {
+            GrGLenum fFormat;
+            GrGLenum fType;
+            GrGLenum fFboFormat;
+
+            bool operator==(const Key& rhs) const {
+                return fFormat == rhs.fFormat
+                        && fType == rhs.fType
+                        && fFboFormat == rhs.fFboFormat;
+            }
+
+            uint32_t getHash() const {
+                // fFormat has different values like 0x190X or 0x8XXX: 16 bits are required
+                uint32_t hash = ((static_cast<uint32_t> (fFormat) & 0xFFFF) << 16);
+                // fType is 0x14XX: 8 lower bits are enough
+                hash |= ((static_cast<uint32_t> (fType) & 0xFF) << 8);
+                // fFboFormat is enum GrPixelConfig which has less than 15 values: 8 bits OK
+                hash |= (static_cast<uint32_t> (fFboFormat) & 0xFF);
+
+                return hash;
+            }
+        };
+        
+        ReadPixelsSupportedFormats(Key key,
+                bool value)
+        : fKey(key), fValue(value) {
+        }
+
+        static const Key& GetKey(const ReadPixelsSupportedFormats& element) {
+            return element.fKey;
+        }
+
+        static uint32_t Hash(const Key& key) {
+            return key.getHash();
+        }
+
+        bool value() const {
+            return fValue;
+        }
+    private:
+        Key fKey;
+        bool fValue;
+    };
+
+    mutable SkTHashCache<ReadPixelsSupportedFormats,
+                         ReadPixelsSupportedFormats::Key> fReadPixelsSupportedCache;
+
     typedef GrDrawTargetCaps INHERITED;
 };