Add subscribeUniform extension pipeline

gpu/command_buffer/service/valuebuffer_manager.h

+// Copyright (c) 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef GPU_COMMAND_BUFFER_SERVICE_VALUEBUFFER_MANAGER_H_
+#define GPU_COMMAND_BUFFER_SERVICE_VALUEBUFFER_MANAGER_H_
+
+#include <set>
+
+#include "base/basictypes.h"
+#include "base/containers/hash_tables.h"
+#include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
+#include "gpu/command_buffer/service/gl_utils.h"
+#include "gpu/gpu_export.h"
+
+namespace gpu {
+namespace gles2 {
+
+class ValuebufferManager;
+
+class ValueState : public base::RefCounted<ValueState> {
+ public:
+  ValueState(GLenum target);
+
+  GLenum target() const { return target_; }
+
+ protected:
+  virtual ~ValueState() = 0;
+
+ private:
+  friend class base::RefCounted<ValueState>;
+
+  GLenum target_;

[piman, 2014/11/04 02:38:22]

You only use target_ for ValuebufferManager::UpdateValueState, but afterwards
it's redundant with the map keys.
I suggest just passing the target to UpdateValueState.

[orglofch, 2014/11/04 19:53:28]

Done.

+};
+
+class IntValueState : public ValueState {

[orglofch, 2014/11/04 01:30:06]

It would be nice to simply store a void* data member in ValueState and cast it
appropriately in UniformValueBuffer (or template the class), but we don't allow
un-scoped ptrs and scoped_ptrs can't encapsulate void. Other alternatives are
welcome.

[piman, 2014/11/04 02:38:22]

My suggestion: given that the number of elements is bounded by 4, I'd just have
ValueState be a union { float float_value[4]; int int_value[4]; }. You can pass
float_value or int_value directly to glUniform[1-4][if]v as appropriate.

Less code, more compact and cache coherent data structures (just the malloc
header + pointer would take more bytes than the actual data). It's most likely a
lot cheaper to copy 16 bytes of data than alloc/free/refcounting, let alone all
the pointer chasing.

[orglofch, 2014/11/04 19:53:29]

Nice, I didn't know about unions! Done.

+ public:
+  IntValueState(GLenum target, GLint* data);
+
+  const GLint* data() const { return data_.get(); }
+
+ private:
+  ~IntValueState();
+
+  scoped_ptr<GLint[]> data_;
+};
+
+class FloatValueState : public ValueState {
+ public:
+  FloatValueState(GLenum target, GLfloat* data);
+
+  const GLfloat* data() const { return data_.get(); }
+
+ private:
+  ~FloatValueState();
+
+  scoped_ptr<GLfloat[]> data_;
+};
+
+class GPU_EXPORT Valuebuffer : public base::RefCounted<Valuebuffer> {
+ public:
+  typedef base::hash_map<GLenum, scoped_refptr<ValueState>> StateMap;
+
+  Valuebuffer(ValuebufferManager* manager, GLuint client_id);
+
+  GLuint client_id() const { return client_id_; }
+
+  bool IsDeleted() const { return client_id_ == 0; }
+
+  void MarkAsValid() { has_been_bound_ = true; }
+
+  bool IsValid() const { return has_been_bound_ && !IsDeleted(); }
+
+  void AddSubscription(GLenum subscription);
+  void RemoveSubscription(GLenum subscription);
+
+  // Returns true if this Valuebuffer is subscribed to subscription
+  bool IsSubscribed(GLenum subscription);
+
+  // Returns the active state for a given target in this Valuebuffer
+  // returns NULL if target state doesn't exist
+  const ValueState* GetState(GLenum target) const;
+
+ private:
+  friend class ValuebufferManager;
+  friend class base::RefCounted<Valuebuffer>;
+
+  typedef std::set<GLenum> SubscriptionSet;

[piman, 2014/11/04 02:38:22]

nit: make this a hash_set, since you don't care about the order. hash_sets are
generally more efficient.
Given that you only expect few entries, a std::vector might even be cheaper.

[orglofch, 2014/11/04 19:53:29]

Done. I'll leave it as a hash_set to it's more extensible.

+
+  ~Valuebuffer();
+
+  void UpdateState(const StateMap& pending_state);
+
+  void MarkAsDeleted() { client_id_ = 0; }
+
+  // ValuebufferManager that owns this Valuebuffer.
+  ValuebufferManager* manager_;
+
+  // Client side Valuebuffer id.
+  GLuint client_id_;
+
+  // Whether this Valuebuffer has ever been bound.
+  bool has_been_bound_;
+
+  SubscriptionSet subscriptions_;
+
+  StateMap active_state_map_;
+};
+
+class GPU_EXPORT ValuebufferManager {
+ public:
+  ValuebufferManager();
+  ~ValuebufferManager();
+
+  // Must call before destruction.
+  void Destroy(bool have_context);
+
+  // Creates a Valuebuffer for the given Valuebuffer ids.
+  void CreateValuebuffer(GLuint client_id);
+
+  // Gets the Valuebuffer for the given Valuebuffer id.
+  Valuebuffer* GetValuebuffer(GLuint client_id);
+
+  // Removes a Valuebuffer for the given Valuebuffer id.
+  void RemoveValuebuffer(GLuint client_id);
+
+  // Updates the value state for the given Valuebuffer
+  void UpdateValuebufferState(GLuint client_id);
+
+  // Gets the state for the given subscription target
+  void UpdateValueState(ValueState* state);
+
+  static uint32 ApiTypeForSubscriptionTarget(GLenum target);
+
+ private:
+  friend class Valuebuffer;
+
+  typedef base::hash_map<GLuint, scoped_refptr<Valuebuffer>> ValuebufferMap;
+
+  void StartTracking(Valuebuffer* valuebuffer);
+  void StopTracking(Valuebuffer* valuebuffer);
+
+  // Counts the number of Valuebuffer allocated with 'this' as its manager.
+  // Allows to check no Valuebuffer will outlive this.
+  unsigned valuebuffer_count_;
+
+  bool have_context_;
+
+  // Info for each Valuebuffer in the system.
+  ValuebufferMap valuebuffer_map_;
+
+  // Current value state in the system
+  Valuebuffer::StateMap pending_state_map_;
+
+  DISALLOW_COPY_AND_ASSIGN(ValuebufferManager);
+};
+
+}  // namespace gles2
+}  // namespace gpu
+
+#endif  // GPU_COMMAND_BUFFER_SERVICE_VALUEBUFFER_MANAGER_H_