cc/resources/resource_provider.h

   1 // Copyright 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 CC_RESOURCES_RESOURCE_PROVIDER_H_
   6 #define CC_RESOURCES_RESOURCE_PROVIDER_H_
   7
   8 #include <deque>
   9 #include <set>
  10 #include <string>
  11 #include <utility>
  12 #include <vector>
  13
  14 #include "base/basictypes.h"
  15 #include "base/callback.h"
  16 #include "base/containers/hash_tables.h"
  17 #include "base/memory/linked_ptr.h"
  18 #include "base/memory/scoped_ptr.h"
  19 #include "base/threading/thread_checker.h"
  20 #include "cc/base/cc_export.h"
  21 #include "cc/base/resource_id.h"
  22 #include "cc/output/context_provider.h"
  23 #include "cc/output/output_surface.h"
  24 #include "cc/resources/release_callback_impl.h"
  25 #include "cc/resources/resource_format.h"
  26 #include "cc/resources/return_callback.h"
  27 #include "cc/resources/shared_bitmap.h"
  28 #include "cc/resources/single_release_callback_impl.h"
  29 #include "cc/resources/texture_mailbox.h"
  30 #include "cc/resources/transferable_resource.h"
  31 #include "third_party/khronos/GLES2/gl2.h"
  32 #include "third_party/khronos/GLES2/gl2ext.h"
  33 #include "third_party/skia/include/core/SkBitmap.h"
  34 #include "third_party/skia/include/core/SkCanvas.h"
  35 #include "ui/gfx/geometry/size.h"
  36
  37 class GrContext;
  38
  39 namespace gpu {
  40 class GpuMemoryBufferManager;
  41 namespace gles {
  42 class GLES2Interface;
  43 }
  44 }
  45
  46 namespace gfx {
  47 class GpuMemoryBuffer;
  48 class Rect;
  49 class Vector2d;
  50 }
  51
  52 namespace cc {
  53 class BlockingTaskRunner;
  54 class IdAllocator;
  55 class SharedBitmap;
  56 class SharedBitmapManager;
  57
  58 // This class is not thread-safe and can only be called from the thread it was
  59 // created on (in practice, the impl thread).
  60 class CC_EXPORT ResourceProvider {
  61  private:
  62   struct Resource;
  63
  64  public:
  65   typedef std::vector<ResourceId> ResourceIdArray;
  66   typedef base::hash_set<ResourceId> ResourceIdSet;
  67   typedef base::hash_map<ResourceId, ResourceId> ResourceIdMap;
  68   enum TextureHint {
  69     TEXTURE_HINT_DEFAULT = 0x0,
  70     TEXTURE_HINT_IMMUTABLE = 0x1,
  71     TEXTURE_HINT_FRAMEBUFFER = 0x2,
  72     TEXTURE_HINT_IMMUTABLE_FRAMEBUFFER =
  73         TEXTURE_HINT_IMMUTABLE | TEXTURE_HINT_FRAMEBUFFER
  74   };
  75   enum ResourceType {
  76     RESOURCE_TYPE_GL_TEXTURE,
  77     RESOURCE_TYPE_BITMAP,
  78   };
  79
  80   static scoped_ptr<ResourceProvider> Create(
  81       OutputSurface* output_surface,
  82       SharedBitmapManager* shared_bitmap_manager,
  83       gpu::GpuMemoryBufferManager* gpu_memory_buffer_manager,
  84       BlockingTaskRunner* blocking_main_thread_task_runner,
  85       int highp_threshold_min,
  86       bool use_rgba_4444_texture_format,
  87       size_t id_allocation_chunk_size,
  88       bool use_persistent_map_for_gpu_memory_buffers);
  89   virtual ~ResourceProvider();
  90
  91   void DidLoseOutputSurface() { lost_output_surface_ = true; }
  92
  93   int max_texture_size() const { return max_texture_size_; }
  94   ResourceFormat memory_efficient_texture_format() const {
  95     return use_rgba_4444_texture_format_ ? RGBA_4444 : best_texture_format_;
  96   }
  97   ResourceFormat best_texture_format() const { return best_texture_format_; }
  98   ResourceFormat best_render_buffer_format() const {
  99     return best_render_buffer_format_;
 100   }
 101   ResourceFormat yuv_resource_format() const { return yuv_resource_format_; }
 102   bool use_sync_query() const { return use_sync_query_; }
 103   bool use_persistent_map_for_gpu_memory_buffers() const {
 104     return use_persistent_map_for_gpu_memory_buffers_;
 105   }
 106   size_t num_resources() const { return resources_.size(); }
 107
 108   // Checks whether a resource is in use by a consumer.
 109   bool InUseByConsumer(ResourceId id);
 110
 111   bool IsLost(ResourceId id);
 112
 113   void LoseResourceForTesting(ResourceId id);
 114   void EnableReadLockFencesForTesting(ResourceId id);
 115
 116   // Producer interface.
 117
 118   ResourceType default_resource_type() const { return default_resource_type_; }
 119   ResourceType GetResourceType(ResourceId id);
 120
 121   // Creates a resource of the default resource type.
 122   ResourceId CreateResource(const gfx::Size& size,
 123                             GLint wrap_mode,
 124                             TextureHint hint,
 125                             ResourceFormat format);
 126
 127   // Creates a resource which is tagged as being managed for GPU memory
 128   // accounting purposes.
 129   ResourceId CreateManagedResource(const gfx::Size& size,
 130                                    GLenum target,
 131                                    GLint wrap_mode,
 132                                    TextureHint hint,
 133                                    ResourceFormat format);
 134
 135   // You can also explicitly create a specific resource type.
 136   ResourceId CreateGLTexture(const gfx::Size& size,
 137                              GLenum target,
 138                              GLenum texture_pool,
 139                              GLint wrap_mode,
 140                              TextureHint hint,
 141                              ResourceFormat format);
 142
 143   ResourceId CreateBitmap(const gfx::Size& size, GLint wrap_mode);
 144   // Wraps an IOSurface into a GL resource.
 145   ResourceId CreateResourceFromIOSurface(const gfx::Size& size,
 146                                          unsigned io_surface_id);
 147
 148   // Wraps an external texture mailbox into a GL resource.
 149   ResourceId CreateResourceFromTextureMailbox(
 150       const TextureMailbox& mailbox,
 151       scoped_ptr<SingleReleaseCallbackImpl> release_callback_impl);
 152
 153   ResourceId CreateResourceFromTextureMailbox(
 154       const TextureMailbox& mailbox,
 155       scoped_ptr<SingleReleaseCallbackImpl> release_callback_impl,
 156       bool read_lock_fences_enabled);
 157
 158   void DeleteResource(ResourceId id);
 159
 160   // Update pixels from image, copying source_rect (in image) to dest_offset (in
 161   // the resource).
 162   void CopyToResource(ResourceId id,
 163                       const uint8_t* image,
 164                       const gfx::Size& image_size);
 165
 166   // Only flush the command buffer if supported.
 167   // Returns true if the shallow flush occurred, false otherwise.
 168   bool ShallowFlushIfSupported();
 169
 170   // Creates accounting for a child. Returns a child ID.
 171   int CreateChild(const ReturnCallback& return_callback);
 172
 173   // Destroys accounting for the child, deleting all accounted resources.
 174   void DestroyChild(int child);
 175
 176   // Sets whether resources need sync points set on them when returned to this
 177   // child. Defaults to true.
 178   void SetChildNeedsSyncPoints(int child, bool needs_sync_points);
 179
 180   // Gets the child->parent resource ID map.
 181   const ResourceIdMap& GetChildToParentMap(int child) const;
 182
 183   // Prepares resources to be transfered to the parent, moving them to
 184   // mailboxes and serializing meta-data into TransferableResources.
 185   // Resources are not removed from the ResourceProvider, but are marked as
 186   // "in use".
 187   void PrepareSendToParent(const ResourceIdArray& resources,
 188                            TransferableResourceArray* transferable_resources);
 189
 190   // Receives resources from a child, moving them from mailboxes. Resource IDs
 191   // passed are in the child namespace, and will be translated to the parent
 192   // namespace, added to the child->parent map.
 193   // This adds the resources to the working set in the ResourceProvider without
 194   // declaring which resources are in use. Use DeclareUsedResourcesFromChild
 195   // after calling this method to do that. All calls to ReceiveFromChild should
 196   // be followed by a DeclareUsedResourcesFromChild.
 197   // NOTE: if the sync_point is set on any TransferableResource, this will
 198   // wait on it.
 199   void ReceiveFromChild(
 200       int child, const TransferableResourceArray& transferable_resources);
 201
 202   // Once a set of resources have been received, they may or may not be used.
 203   // This declares what set of resources are currently in use from the child,
 204   // releasing any other resources back to the child.
 205   void DeclareUsedResourcesFromChild(int child,
 206                                      const ResourceIdSet& resources_from_child);
 207
 208   // Receives resources from the parent, moving them from mailboxes. Resource
 209   // IDs passed are in the child namespace.
 210   // NOTE: if the sync_point is set on any TransferableResource, this will
 211   // wait on it.
 212   void ReceiveReturnsFromParent(
 213       const ReturnedResourceArray& transferable_resources);
 214
 215   // The following lock classes are part of the ResourceProvider API and are
 216   // needed to read and write the resource contents. The user must ensure
 217   // that they only use GL locks on GL resources, etc, and this is enforced
 218   // by assertions.
 219   class CC_EXPORT ScopedReadLockGL {
 220    public:
 221     ScopedReadLockGL(ResourceProvider* resource_provider,
 222                      ResourceId resource_id);
 223     virtual ~ScopedReadLockGL();
 224
 225     unsigned texture_id() const { return resource_->gl_id; }
 226     GLenum target() const { return resource_->target; }
 227
 228    protected:
 229     ResourceProvider* resource_provider_;
 230     ResourceId resource_id_;
 231
 232    private:
 233     const ResourceProvider::Resource* resource_;
 234
 235     DISALLOW_COPY_AND_ASSIGN(ScopedReadLockGL);
 236   };
 237
 238   class CC_EXPORT ScopedSamplerGL : public ScopedReadLockGL {
 239    public:
 240     ScopedSamplerGL(ResourceProvider* resource_provider,
 241                     ResourceId resource_id,
 242                     GLenum filter);
 243     ScopedSamplerGL(ResourceProvider* resource_provider,
 244                     ResourceId resource_id,
 245                     GLenum unit,
 246                     GLenum filter);
 247     ~ScopedSamplerGL() override;
 248
 249     GLenum target() const { return target_; }
 250
 251    private:
 252     GLenum unit_;
 253     GLenum target_;
 254
 255     DISALLOW_COPY_AND_ASSIGN(ScopedSamplerGL);
 256   };
 257
 258   class CC_EXPORT ScopedWriteLockGL {
 259    public:
 260     ScopedWriteLockGL(ResourceProvider* resource_provider,
 261                       ResourceId resource_id);
 262     ~ScopedWriteLockGL();
 263
 264     unsigned texture_id() const { return texture_id_; }
 265
 266    private:
 267     ResourceProvider* resource_provider_;
 268     ResourceProvider::Resource* resource_;
 269     unsigned texture_id_;
 270
 271     DISALLOW_COPY_AND_ASSIGN(ScopedWriteLockGL);
 272   };
 273
 274   class CC_EXPORT ScopedReadLockSoftware {
 275    public:
 276     ScopedReadLockSoftware(ResourceProvider* resource_provider,
 277                            ResourceId resource_id);
 278     ~ScopedReadLockSoftware();
 279
 280     const SkBitmap* sk_bitmap() const {
 281       DCHECK(valid());
 282       return &sk_bitmap_;
 283     }
 284     GLint wrap_mode() const { return wrap_mode_; }
 285
 286     bool valid() const { return !!sk_bitmap_.getPixels(); }
 287
 288    private:
 289     ResourceProvider* resource_provider_;
 290     ResourceId resource_id_;
 291     SkBitmap sk_bitmap_;
 292     GLint wrap_mode_;
 293
 294     DISALLOW_COPY_AND_ASSIGN(ScopedReadLockSoftware);
 295   };
 296
 297   class CC_EXPORT ScopedWriteLockSoftware {
 298    public:
 299     ScopedWriteLockSoftware(ResourceProvider* resource_provider,
 300                             ResourceId resource_id);
 301     ~ScopedWriteLockSoftware();
 302
 303     SkBitmap& sk_bitmap() { return sk_bitmap_; }
 304     bool valid() const { return !!sk_bitmap_.getPixels(); }
 305
 306    private:
 307     ResourceProvider* resource_provider_;
 308     ResourceProvider::Resource* resource_;
 309     SkBitmap sk_bitmap_;
 310     base::ThreadChecker thread_checker_;
 311
 312     DISALLOW_COPY_AND_ASSIGN(ScopedWriteLockSoftware);
 313   };
 314
 315   class CC_EXPORT ScopedWriteLockGpuMemoryBuffer {
 316    public:
 317     ScopedWriteLockGpuMemoryBuffer(ResourceProvider* resource_provider,
 318                                    ResourceId resource_id);
 319     ~ScopedWriteLockGpuMemoryBuffer();
 320
 321     gfx::GpuMemoryBuffer* GetGpuMemoryBuffer();
 322
 323    private:
 324     ResourceProvider* resource_provider_;
 325     ResourceProvider::Resource* resource_;
 326     gpu::GpuMemoryBufferManager* gpu_memory_buffer_manager_;
 327     gfx::GpuMemoryBuffer* gpu_memory_buffer_;
 328     gfx::Size size_;
 329     ResourceFormat format_;
 330     base::ThreadChecker thread_checker_;
 331
 332     DISALLOW_COPY_AND_ASSIGN(ScopedWriteLockGpuMemoryBuffer);
 333   };
 334
 335   class CC_EXPORT ScopedWriteLockGr {
 336    public:
 337     ScopedWriteLockGr(ResourceProvider* resource_provider,
 338                       ResourceId resource_id);
 339     ~ScopedWriteLockGr();
 340
 341     void InitSkSurface(bool use_distance_field_text,
 342                        bool can_use_lcd_text,
 343                        int msaa_sample_count);
 344     void ReleaseSkSurface();
 345
 346     SkSurface* sk_surface() { return sk_surface_.get(); }
 347     ResourceProvider::Resource* resource() { return resource_; }
 348
 349    private:
 350     ResourceProvider* resource_provider_;
 351     ResourceProvider::Resource* resource_;
 352     base::ThreadChecker thread_checker_;
 353     skia::RefPtr<SkSurface> sk_surface_;
 354
 355     DISALLOW_COPY_AND_ASSIGN(ScopedWriteLockGr);
 356   };
 357
 358   class Fence : public base::RefCounted<Fence> {
 359    public:
 360     Fence() {}
 361
 362     virtual void Set() = 0;
 363     virtual bool HasPassed() = 0;
 364     virtual void Wait() = 0;
 365
 366    protected:
 367     friend class base::RefCounted<Fence>;
 368     virtual ~Fence() {}
 369
 370    private:
 371     DISALLOW_COPY_AND_ASSIGN(Fence);
 372   };
 373
 374   class SynchronousFence : public ResourceProvider::Fence {
 375    public:
 376     explicit SynchronousFence(gpu::gles2::GLES2Interface* gl);
 377
 378     // Overridden from Fence:
 379     void Set() override;
 380     bool HasPassed() override;
 381     void Wait() override;
 382
 383     // Returns true if fence has been set but not yet synchornized.
 384     bool has_synchronized() const { return has_synchronized_; }
 385
 386    private:
 387     ~SynchronousFence() override;
 388
 389     void Synchronize();
 390
 391     gpu::gles2::GLES2Interface* gl_;
 392     bool has_synchronized_;
 393
 394     DISALLOW_COPY_AND_ASSIGN(SynchronousFence);
 395   };
 396
 397   // Acquire pixel buffer for resource. The pixel buffer can be used to
 398   // set resource pixels without performing unnecessary copying.
 399   void AcquirePixelBuffer(ResourceId resource);
 400   void ReleasePixelBuffer(ResourceId resource);
 401   // Map/unmap the acquired pixel buffer.
 402   uint8_t* MapPixelBuffer(ResourceId id, int* stride);
 403   void UnmapPixelBuffer(ResourceId id);
 404   // Asynchronously update pixels from acquired pixel buffer.
 405   void BeginSetPixels(ResourceId id);
 406   void ForceSetPixelsToComplete(ResourceId id);
 407   bool DidSetPixelsComplete(ResourceId id);
 408
 409   // For tests only! This prevents detecting uninitialized reads.
 410   // Use SetPixels or LockForWrite to allocate implicitly.
 411   void AllocateForTesting(ResourceId id);
 412
 413   // For tests only!
 414   void CreateForTesting(ResourceId id);
 415
 416   GLenum TargetForTesting(ResourceId id);
 417
 418   // Sets the current read fence. If a resource is locked for read
 419   // and has read fences enabled, the resource will not allow writes
 420   // until this fence has passed.
 421   void SetReadLockFence(Fence* fence) { current_read_lock_fence_ = fence; }
 422
 423   // Indicates if we can currently lock this resource for write.
 424   bool CanLockForWrite(ResourceId id);
 425
 426   // Copy |rect| pixels from source to destination.
 427   void CopyResource(ResourceId source_id,
 428                     ResourceId dest_id,
 429                     const gfx::Rect& rect);
 430
 431   void WaitSyncPointIfNeeded(ResourceId id);
 432
 433   void WaitReadLockIfNeeded(ResourceId id);
 434
 435   static GLint GetActiveTextureUnit(gpu::gles2::GLES2Interface* gl);
 436
 437   OutputSurface* output_surface() { return output_surface_; }
 438
 439   void ValidateResource(ResourceId id) const;
 440
 441  protected:
 442   ResourceProvider(OutputSurface* output_surface,
 443                    SharedBitmapManager* shared_bitmap_manager,
 444                    gpu::GpuMemoryBufferManager* gpu_memory_buffer_manager,
 445                    BlockingTaskRunner* blocking_main_thread_task_runner,
 446                    int highp_threshold_min,
 447                    bool use_rgba_4444_texture_format,
 448                    size_t id_allocation_chunk_size,
 449                    bool use_persistent_map_for_gpu_memory_buffers);
 450   void Initialize();
 451
 452  private:
 453   struct Resource {
 454     enum Origin { INTERNAL, EXTERNAL, DELEGATED };
 455
 456     ~Resource();
 457     Resource(unsigned texture_id,
 458              const gfx::Size& size,
 459              Origin origin,
 460              GLenum target,
 461              GLenum filter,
 462              GLenum texture_pool,
 463              GLint wrap_mode,
 464              TextureHint hint,
 465              ResourceFormat format);
 466     Resource(uint8_t* pixels,
 467              SharedBitmap* bitmap,
 468              const gfx::Size& size,
 469              Origin origin,
 470              GLenum filter,
 471              GLint wrap_mode);
 472     Resource(const SharedBitmapId& bitmap_id,
 473              const gfx::Size& size,
 474              Origin origin,
 475              GLenum filter,
 476              GLint wrap_mode);
 477
 478     int child_id;
 479     unsigned gl_id;
 480     // Pixel buffer used for set pixels without unnecessary copying.
 481     unsigned gl_pixel_buffer_id;
 482     // Query used to determine when asynchronous set pixels complete.
 483     unsigned gl_upload_query_id;
 484     // Query used to determine when read lock fence has passed.
 485     unsigned gl_read_lock_query_id;
 486     TextureMailbox mailbox;
 487     ReleaseCallbackImpl release_callback_impl;
 488     uint8_t* pixels;
 489     int lock_for_read_count;
 490     int imported_count;
 491     int exported_count;
 492     bool dirty_image : 1;
 493     bool locked_for_write : 1;
 494     bool lost : 1;
 495     bool marked_for_deletion : 1;
 496     bool pending_set_pixels : 1;
 497     bool set_pixels_completion_forced : 1;
 498     bool allocated : 1;
 499     bool read_lock_fences_enabled : 1;
 500     bool has_shared_bitmap_id : 1;
 501     scoped_refptr<Fence> read_lock_fence;
 502     gfx::Size size;
 503     Origin origin;
 504     GLenum target;
 505     // TODO(skyostil): Use a separate sampler object for filter state.
 506     GLenum original_filter;
 507     GLenum filter;
 508     unsigned image_id;
 509     unsigned bound_image_id;
 510     GLenum texture_pool;
 511     GLint wrap_mode;
 512     TextureHint hint;
 513     ResourceType type;
 514     ResourceFormat format;
 515     SharedBitmapId shared_bitmap_id;
 516     SharedBitmap* shared_bitmap;
 517     gfx::GpuMemoryBuffer* gpu_memory_buffer;
 518   };
 519   typedef base::hash_map<ResourceId, Resource> ResourceMap;
 520
 521   struct Child {
 522     Child();
 523     ~Child();
 524
 525     ResourceIdMap child_to_parent_map;
 526     ResourceIdMap parent_to_child_map;
 527     ReturnCallback return_callback;
 528     bool marked_for_deletion;
 529     bool needs_sync_points;
 530   };
 531   typedef base::hash_map<int, Child> ChildMap;
 532
 533   bool ReadLockFenceHasPassed(const Resource* resource) {
 534     return !resource->read_lock_fence.get() ||
 535            resource->read_lock_fence->HasPassed();
 536   }
 537
 538   Resource* InsertResource(ResourceId id, const Resource& resource);
 539   Resource* GetResource(ResourceId id);
 540   const Resource* LockForRead(ResourceId id);
 541   void UnlockForRead(ResourceId id);
 542   Resource* LockForWrite(ResourceId id);
 543   void UnlockForWrite(Resource* resource);
 544
 545   static void PopulateSkBitmapWithResource(SkBitmap* sk_bitmap,
 546                                            const Resource* resource);
 547
 548   void TransferResource(gpu::gles2::GLES2Interface* gl,
 549                         ResourceId id,
 550                         TransferableResource* resource);
 551   enum DeleteStyle {
 552     NORMAL,
 553     FOR_SHUTDOWN,
 554   };
 555   void DeleteResourceInternal(ResourceMap::iterator it, DeleteStyle style);
 556   void DeleteAndReturnUnusedResourcesToChild(ChildMap::iterator child_it,
 557                                              DeleteStyle style,
 558                                              const ResourceIdArray& unused);
 559   void DestroyChildInternal(ChildMap::iterator it, DeleteStyle style);
 560   void LazyCreate(Resource* resource);
 561   void LazyAllocate(Resource* resource);
 562
 563   void BindImageForSampling(Resource* resource);
 564   // Binds the given GL resource to a texture target for sampling using the
 565   // specified filter for both minification and magnification. Returns the
 566   // texture target used. The resource must be locked for reading.
 567   GLenum BindForSampling(ResourceId resource_id, GLenum unit, GLenum filter);
 568
 569   // Returns NULL if the output_surface_ does not have a ContextProvider.
 570   gpu::gles2::GLES2Interface* ContextGL() const;
 571   class GrContext* GrContext(bool worker_context) const;
 572
 573   OutputSurface* output_surface_;
 574   SharedBitmapManager* shared_bitmap_manager_;
 575   gpu::GpuMemoryBufferManager* gpu_memory_buffer_manager_;
 576   BlockingTaskRunner* blocking_main_thread_task_runner_;
 577   bool lost_output_surface_;
 578   int highp_threshold_min_;
 579   ResourceId next_id_;
 580   ResourceMap resources_;
 581   int next_child_;
 582   ChildMap children_;
 583
 584   ResourceType default_resource_type_;
 585   bool use_texture_storage_ext_;
 586   bool use_texture_format_bgra_;
 587   bool use_texture_usage_hint_;
 588   bool use_compressed_texture_etc1_;
 589   ResourceFormat yuv_resource_format_;
 590   int max_texture_size_;
 591   ResourceFormat best_texture_format_;
 592   ResourceFormat best_render_buffer_format_;
 593
 594   base::ThreadChecker thread_checker_;
 595
 596   scoped_refptr<Fence> current_read_lock_fence_;
 597   bool use_rgba_4444_texture_format_;
 598
 599   const size_t id_allocation_chunk_size_;
 600   scoped_ptr<IdAllocator> texture_id_allocator_;
 601   scoped_ptr<IdAllocator> buffer_id_allocator_;
 602
 603   bool use_sync_query_;
 604   bool use_persistent_map_for_gpu_memory_buffers_;
 605   // Fence used for CopyResource if CHROMIUM_sync_query is not supported.
 606   scoped_refptr<SynchronousFence> synchronous_fence_;
 607
 608   DISALLOW_COPY_AND_ASSIGN(ResourceProvider);
 609 };
 610
 611 // TODO(epenner): Move these format conversions to resource_format.h
 612 // once that builds on mac (npapi.h currently #includes OpenGL.h).
 613 inline int BitsPerPixel(ResourceFormat format) {
 614   switch (format) {
 615     case BGRA_8888:
 616     case RGBA_8888:
 617       return 32;
 618     case RGBA_4444:
 619     case RGB_565:
 620       return 16;
 621     case ALPHA_8:
 622     case LUMINANCE_8:
 623     case RED_8:
 624       return 8;
 625     case ETC1:
 626       return 4;
 627   }
 628   NOTREACHED();
 629   return 0;
 630 }
 631
 632 inline GLenum GLDataType(ResourceFormat format) {
 633   DCHECK_LE(format, RESOURCE_FORMAT_MAX);
 634   static const unsigned format_gl_data_type[RESOURCE_FORMAT_MAX + 1] = {
 635       GL_UNSIGNED_BYTE,           // RGBA_8888
 636       GL_UNSIGNED_SHORT_4_4_4_4,  // RGBA_4444
 637       GL_UNSIGNED_BYTE,           // BGRA_8888
 638       GL_UNSIGNED_BYTE,           // ALPHA_8
 639       GL_UNSIGNED_BYTE,           // LUMINANCE_8
 640       GL_UNSIGNED_SHORT_5_6_5,    // RGB_565,
 641       GL_UNSIGNED_BYTE,           // ETC1
 642       GL_UNSIGNED_BYTE            // RED_8
 643   };
 644   return format_gl_data_type[format];
 645 }
 646
 647 inline GLenum GLDataFormat(ResourceFormat format) {
 648   DCHECK_LE(format, RESOURCE_FORMAT_MAX);
 649   static const unsigned format_gl_data_format[RESOURCE_FORMAT_MAX + 1] = {
 650       GL_RGBA,           // RGBA_8888
 651       GL_RGBA,           // RGBA_4444
 652       GL_BGRA_EXT,       // BGRA_8888
 653       GL_ALPHA,          // ALPHA_8
 654       GL_LUMINANCE,      // LUMINANCE_8
 655       GL_RGB,            // RGB_565
 656       GL_ETC1_RGB8_OES,  // ETC1
 657       GL_RED_EXT         // RED_8
 658   };
 659   return format_gl_data_format[format];
 660 }
 661
 662 inline GLenum GLInternalFormat(ResourceFormat format) {
 663   return GLDataFormat(format);
 664 }
 665
 666 }  // namespace cc
 667
 668 #endif  // CC_RESOURCES_RESOURCE_PROVIDER_H_