text: /*
   * Copyright (C) 2011 Apple Inc. All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   *
   * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
   * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
   * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
   * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
   * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
   * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
   * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
   * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  
  #ifndef THIRD_PARTY_BLINK_RENDERER_MODULES_WEBGL_WEBGL_CONTEXT_GROUP_H_
  #define THIRD_PARTY_BLINK_RENDERER_MODULES_WEBGL_WEBGL_CONTEXT_GROUP_H_
  
  #include "base/macros.h"
  #include "base/memory/scoped_refptr.h"
  #include "third_party/blink/renderer/modules/webgl/webgl_rendering_context_base.h"
  #include "third_party/blink/renderer/platform/bindings/name_client.h"
  #include "third_party/blink/renderer/platform/wtf/hash_set.h"
  #include "third_party/blink/renderer/platform/wtf/ref_counted.h"
  
  namespace blink {
  
  class WebGLContextGroup final : public GarbageCollected<WebGLContextGroup>,
                                  public NameClient {
   public:
    WebGLContextGroup();
  
    void AddContext(WebGLRenderingContextBase*);
  
    // There's no point in having a removeContext method any more now that
    // the context group is GarbageCollected. The only time it would be
    // called would be during WebGLRenderingContext destruction, and at that
    // time, the context is not allowed to refer back to the context group
    // since both are on the Oilpan heap.
  
    gpu::gles2::GLES2Interface* GetAGLInterface();
  
    void LoseContextGroup(WebGLRenderingContextBase::LostContextMode,
                          WebGLRenderingContextBase::AutoRecoveryMethod);
  
    // This counter gets incremented every time context loss is
    // triggered. Because there's no longer any explicit enumeration of
    // the objects in a given context group upon context loss, each
    // object needs to keep track of the context loss count when it was
    // created, in order to validate itself.
    uint32_t NumberOfContextLosses() const;
  
    void Trace(Visitor* visitor) { visitor->Trace(contexts_); }
    const char* NameInHeapSnapshot() const override {
      return "WebGLContextGroup";
    }
  
   private:
    friend class WebGLObject;
  
    uint32_t number_of_context_losses_;
  
    HeapHashSet<Member<WebGLRenderingContextBase>> contexts_;
  
    DISALLOW_COPY_AND_ASSIGN(WebGLContextGroup);
  };
  
  }  // namespace blink
  
  #endif  // THIRD_PARTY_BLINK_RENDERER_MODULES_WEBGL_WEBGL_CONTEXT_GROUP_H_
  