Modified GPU command signature hash to use a binary representation.

gpu/command_buffer/service/renderbuffer_manager.cc

Index: gpu/command_buffer/service/renderbuffer_manager.cc
diff --git a/gpu/command_buffer/service/renderbuffer_manager.cc b/gpu/command_buffer/service/renderbuffer_manager.cc
index 03c37cbe2f6ea735343467763d4fe47fc2814c8e..d034fee0c1043a6ab3edf45aa76749c0f3d7fc11 100644
--- a/gpu/command_buffer/service/renderbuffer_manager.cc
+++ b/gpu/command_buffer/service/renderbuffer_manager.cc
@@ -48,9 +48,12 @@ size_t Renderbuffer::EstimatedSize() {
 void Renderbuffer::AddToSignature(
     std::string* signature) const {
   DCHECK(signature);
-  *signature += base::StringPrintf(
-      "|Renderbuffer|internal_format=%04x|samples=%d|width=%d|height=%d",
-      internal_format_, samples_, width_, height_);
+  signature->append("|Renderbuffer|");
+  signature->append(reinterpret_cast<const char*>(&internal_format_),
+                    sizeof(internal_format_));
+  signature->append(reinterpret_cast<const char*>(&samples_), sizeof(samples_));
+  signature->append(reinterpret_cast<const char*>(&width_), sizeof(width_));
+  signature->append(reinterpret_cast<const char*>(&height_), sizeof(height_));

[vmiura, 2014/09/23 20:26:47]

Could this be improved by packing the values in a struct, then appending to the
signature in one go?  Or if the values were already in a struct ready to append?

[David Yen, 2014/09/23 20:45:24]

I'll create a structure to do this.

 }
 
 Renderbuffer::Renderbuffer(RenderbufferManager* manager,