ui/gl/gl_context.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef UI_GL_GL_CONTEXT_H_
   6 #define UI_GL_GL_CONTEXT_H_
   7
   8 #include <string>
   9 #include <vector>
  10
  11 #include "base/basictypes.h"
  12 #include "base/cancelable_callback.h"
  13 #include "base/memory/ref_counted.h"
  14 #include "base/memory/scoped_ptr.h"
  15 #include "base/synchronization/cancellation_flag.h"
  16 #include "ui/gl/gl_share_group.h"
  17 #include "ui/gl/gl_state_restorer.h"
  18 #include "ui/gl/gpu_preference.h"
  19
  20 namespace gpu {
  21 class GLContextVirtual;
  22 }  // namespace gpu
  23
  24 namespace gfx {
  25
  26 class GLSurface;
  27 class GPUTiming;
  28 class GPUTimingClient;
  29 class VirtualGLApi;
  30 struct GLVersionInfo;
  31
  32
  33 // Encapsulates an OpenGL context, hiding platform specific management.
  34 class GL_EXPORT GLContext : public base::RefCounted<GLContext> {
  35  public:
  36   explicit GLContext(GLShareGroup* share_group);
  37
  38   // Initializes the GL context to be compatible with the given surface. The GL
  39   // context can be made with other surface's of the same type. The compatible
  40   // surface is only needed for certain platforms like WGL, OSMesa and GLX. It
  41   // should be specific for all platforms though.
  42   virtual bool Initialize(
  43       GLSurface* compatible_surface, GpuPreference gpu_preference) = 0;
  44
  45   // Destroys the GL context.
  46   virtual void Destroy() = 0;
  47
  48   // Makes the GL context and a surface current on the current thread.
  49   virtual bool MakeCurrent(GLSurface* surface) = 0;
  50
  51   // Releases this GL context and surface as current on the current thread.
  52   virtual void ReleaseCurrent(GLSurface* surface) = 0;
  53
  54   // Returns true if this context and surface is current. Pass a null surface
  55   // if the current surface is not important.
  56   virtual bool IsCurrent(GLSurface* surface) = 0;
  57
  58   // Get the underlying platform specific GL context "handle".
  59   virtual void* GetHandle() = 0;
  60
  61   // Creates a GPUTimingClient class which abstracts various GPU Timing exts.
  62   virtual scoped_refptr<gfx::GPUTimingClient> CreateGPUTimingClient() = 0;
  63
  64   // Gets the GLStateRestorer for the context.
  65   GLStateRestorer* GetGLStateRestorer();
  66
  67   // Sets the GLStateRestorer for the context (takes ownership).
  68   void SetGLStateRestorer(GLStateRestorer* state_restorer);
  69
  70   // Set swap interval. This context must be current.
  71   void SetSwapInterval(int interval);
  72
  73   // Forces the swap interval to zero (no vsync) regardless of any future values
  74   // passed to SetSwapInterval.
  75   void ForceSwapIntervalZero(bool force);
  76
  77   // Returns space separated list of extensions. The context must be current.
  78   virtual std::string GetExtensions();
  79
  80   // Returns in bytes the total amount of GPU memory for the GPU which this
  81   // context is currently rendering on. Returns false if no extension exists
  82   // to get the exact amount of GPU memory.
  83   virtual bool GetTotalGpuMemory(size_t* bytes);
  84
  85   // Indicate that it is safe to force this context to switch GPUs, since
  86   // transitioning can cause corruption and hangs (OS X only).
  87   virtual void SetSafeToForceGpuSwitch();
  88
  89   // Attempt to force the context to move to the GPU of its sharegroup. Return
  90   // false only in the event of an unexpected error on the context.
  91   virtual bool ForceGpuSwitchIfNeeded();
  92
  93   // Indicate that the real context switches should unbind the FBO first
  94   // (For an Android work-around only).
  95   virtual void SetUnbindFboOnMakeCurrent();
  96
  97   // Returns whether the current context supports the named extension. The
  98   // context must be current.
  99   bool HasExtension(const char* name);
 100
 101   // Returns version info of the underlying GL context. The context must be
 102   // current.
 103   const GLVersionInfo* GetVersionInfo();
 104
 105   GLShareGroup* share_group();
 106
 107   // Create a GL context that is compatible with the given surface.
 108   // |share_group|, if non-NULL, is a group of contexts which the
 109   // internally created OpenGL context shares textures and other resources.
 110   static scoped_refptr<GLContext> CreateGLContext(
 111       GLShareGroup* share_group,
 112       GLSurface* compatible_surface,
 113       GpuPreference gpu_preference);
 114
 115   static bool LosesAllContextsOnContextLost();
 116
 117   // Returns the last GLContext made current, virtual or real.
 118   static GLContext* GetCurrent();
 119
 120   virtual bool WasAllocatedUsingRobustnessExtension();
 121
 122   // Use this context for virtualization.
 123   void SetupForVirtualization();
 124
 125   // Make this context current when used for context virtualization.
 126   bool MakeVirtuallyCurrent(GLContext* virtual_context, GLSurface* surface);
 127
 128   // Notify this context that |virtual_context|, that was using us, is
 129   // being released or destroyed.
 130   void OnReleaseVirtuallyCurrent(GLContext* virtual_context);
 131
 132   // Returns the GL version string. The context must be current.
 133   virtual std::string GetGLVersion();
 134
 135   // Returns the GL renderer string. The context must be current.
 136   virtual std::string GetGLRenderer();
 137
 138   // Return a callback that, when called, indicates that the state the
 139   // underlying context has been changed by code outside of the command buffer,
 140   // and will need to be restored.
 141   virtual base::Closure GetStateWasDirtiedExternallyCallback();
 142
 143   // Restore the context's state if it was dirtied by an external caller.
 144   virtual void RestoreStateIfDirtiedExternally();
 145
 146  protected:
 147   virtual ~GLContext();
 148
 149   // Will release the current context when going out of scope, unless canceled.
 150   class ScopedReleaseCurrent {
 151    public:
 152     ScopedReleaseCurrent();
 153     ~ScopedReleaseCurrent();
 154
 155     void Cancel();
 156
 157    private:
 158     bool canceled_;
 159   };
 160
 161   // Sets the GL api to the real hardware API (vs the VirtualAPI)
 162   static void SetRealGLApi();
 163   virtual void SetCurrent(GLSurface* surface);
 164
 165   // Initialize function pointers to functions where the bound version depends
 166   // on GL version or supported extensions. Should be called immediately after
 167   // this context is made current.
 168   bool InitializeDynamicBindings();
 169
 170   // Returns the last real (non-virtual) GLContext made current.
 171   static GLContext* GetRealCurrent();
 172
 173   virtual void OnSetSwapInterval(int interval) = 0;
 174
 175   bool GetStateWasDirtiedExternally() const;
 176   void SetStateWasDirtiedExternally(bool dirtied_externally);
 177
 178  private:
 179   friend class base::RefCounted<GLContext>;
 180
 181   // For GetRealCurrent.
 182   friend class VirtualGLApi;
 183   friend class gpu::GLContextVirtual;
 184
 185   scoped_refptr<GLShareGroup> share_group_;
 186   scoped_ptr<VirtualGLApi> virtual_gl_api_;
 187   bool state_dirtied_externally_;
 188   scoped_ptr<GLStateRestorer> state_restorer_;
 189   scoped_ptr<GLVersionInfo> version_info_;
 190
 191   int swap_interval_;
 192   bool force_swap_interval_zero_;
 193
 194   base::CancelableCallback<void()> state_dirtied_callback_;
 195
 196   DISALLOW_COPY_AND_ASSIGN(GLContext);
 197 };
 198
 199 class GL_EXPORT GLContextReal : public GLContext {
 200  public:
 201   explicit GLContextReal(GLShareGroup* share_group);
 202   scoped_refptr<gfx::GPUTimingClient> CreateGPUTimingClient() override;
 203
 204  protected:
 205   ~GLContextReal() override;
 206
 207   void SetCurrent(GLSurface* surface) override;
 208
 209  private:
 210   scoped_ptr<gfx::GPUTiming> gpu_timing_;
 211   DISALLOW_COPY_AND_ASSIGN(GLContextReal);
 212 };
 213
 214 }  // namespace gfx
 215
 216 #endif  // UI_GL_GL_CONTEXT_H_