Adds support for the GL_ANGLE_texture_usage and GL_EXT_texture_storage

gpu/command_buffer/service/texture_manager.h

 // Copyright (c) 2011 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_TEXTURE_MANAGER_H_
 #define GPU_COMMAND_BUFFER_SERVICE_TEXTURE_MANAGER_H_
 
 #include <vector>
 #include "base/basictypes.h"
 #include "base/hash_tables.h"
@@ skipping 22 matching lines @@
     explicit TextureInfo(GLuint service_id)
         : service_id_(service_id),
           deleted_(false),
           cleared_(true),
           num_uncleared_mips_(0),
           target_(0),
           min_filter_(GL_NEAREST_MIPMAP_LINEAR),
           mag_filter_(GL_LINEAR),
           wrap_s_(GL_REPEAT),
           wrap_t_(GL_REPEAT),
+          usage_(GL_NONE),
           max_level_set_(-1),
           texture_complete_(false),
           cube_complete_(false),
           npot_(false),
           has_been_bound_(false),
           framebuffer_attachment_count_(0),
           owned_(true),
-          stream_texture_(false) {
+          stream_texture_(false),
+          immutable_(false) {
     }
 
     GLenum min_filter() const {
       return min_filter_;
     }
 
     GLenum mag_filter() const {
       return mag_filter_;
     }
 
     GLenum wrap_s() const {
       return wrap_s_;
     }
 
     GLenum wrap_t() const {
       return wrap_t_;
     }
 
+    GLenum usage() const {
+      return usage_;
+    }
+
     int num_uncleared_mips() const {
       return num_uncleared_mips_;
     }
 
     // True if this texture meets all the GLES2 criteria for rendering.
     // See section 3.8.2 of the GLES2 spec.
     bool CanRender(const FeatureInfo* feature_info) const;
 
     bool CanRenderTo() const {
       return !stream_texture_ && target_ != GL_TEXTURE_EXTERNAL_OES;
@@ skipping 83 matching lines @@
     }
 
     void SetStreamTexture(bool stream_texture) {
       stream_texture_ = stream_texture;
     }
 
     int IsStreamTexture() {
       return stream_texture_;
     }
 
+    void SetImmutable(bool immutable) {
+      immutable_ = immutable;

[greggman, 2011/12/03 01:41:01]

DCHECK(!immutable_) ?

+    }
+
+    bool IsImmutable() {
+      return immutable_;
+    }
+
     // Whether a particular level/face is cleared.
     bool IsLevelCleared(GLenum target, GLint level);
 
    private:
     friend class TextureManager;
     friend class base::RefCounted<TextureInfo>;
 
     ~TextureInfo() { }
 
     struct LevelInfo {
@@ skipping 50 matching lines @@
     // Returns false if a GL error was generated.
     bool ClearLevel(GLES2Decoder* decoder, GLenum target, GLint level);
 
     // Sets a texture parameter.
     // TODO(gman): Expand to SetParameteri,f,iv,fv
     // Returns false if param was INVALID_ENUN
     bool SetParameter(
         const FeatureInfo* feature_info, GLenum pname, GLint param);
 
     // Makes each of the mip levels as though they were generated.
-    bool MarkMipmapsGenerated(const FeatureInfo* feature_info);
+    bool MarkMipmapsGenerated(const FeatureInfo* feature_info, bool cleared);
 
     void MarkAsDeleted() {
       service_id_ = 0;
       deleted_ = true;
     }
 
     bool NeedsMips() const {
       return min_filter_ != GL_NEAREST && min_filter_ != GL_LINEAR;
     }
 
@@ skipping 22 matching lines @@
     int num_uncleared_mips_;
 
     // The target. 0 if unset, otherwise GL_TEXTURE_2D or GL_TEXTURE_CUBE_MAP.
     GLenum target_;
 
     // Texture parameters.
     GLenum min_filter_;
     GLenum mag_filter_;
     GLenum wrap_s_;
     GLenum wrap_t_;
+    GLenum usage_;
 
     // The maximum level that has been set.
     GLint max_level_set_;
 
     // Whether or not this texture is "texture complete"
     bool texture_complete_;
 
     // Whether or not this texture is "cube complete"
     bool cube_complete_;
 
     // Whether or not this texture is non-power-of-two
     bool npot_;
 
     // Whether this texture has ever been bound.
     bool has_been_bound_;
 
     // The number of framebuffers this texture is attached to.
     int framebuffer_attachment_count_;
 
     // Whether the associated context group owns this texture and should delete
     // it.
     bool owned_;
 
     // Whether this is a special streaming texture.
     bool stream_texture_;
 
+    // Whether the texture is immutable and no further changes to the format
+    // or dimensions of the texture object can be made.
+    bool immutable_;
+
     DISALLOW_COPY_AND_ASSIGN(TextureInfo);
   };
 
   TextureManager(GLsizei max_texture_size,
                  GLsizei max_cube_map_texture_size);
   ~TextureManager();
 
   // Init the texture manager.
   bool Initialize(const FeatureInfo* feature_info);
 
@@ skipping 16 matching lines @@
   GLsizei MaxSizeForTarget(GLenum target) const {
     switch (target) {
       case GL_TEXTURE_2D:
       case GL_TEXTURE_EXTERNAL_OES:
         return max_texture_size_;
       default:
         return max_cube_map_texture_size_;
     }
   }
 
+  // Returns the maxium number of levels a texture of the given size can have.
+  static GLsizei ComputeMipMapCount(
+    GLsizei width, GLsizei height, GLsizei depth);
+
   // Checks if a dimensions are valid for a given target.
   bool ValidForTarget(
       const FeatureInfo* feature_info,
       GLenum target, GLint level,
       GLsizei width, GLsizei height, GLsizei depth);
 
   // Sets the TextureInfo's target
   // Parameters:
   //   target: GL_TEXTURE_2D or GL_TEXTURE_CUBE_MAP
   //   max_levels: The maximum levels this type of target can have.
@@ skipping 21 matching lines @@
   void SetLevelCleared(TextureInfo* info, GLenum target, GLint level);
 
   // Sets a texture parameter of a TextureInfo
   // TODO(gman): Expand to SetParameteri,f,iv,fv
   bool SetParameter(
       const FeatureInfo* feature_info,
       TextureInfo* info, GLenum pname, GLint param);
 
   // Makes each of the mip levels as though they were generated.
   // Returns false if that's not allowed for the given texture.
-  bool MarkMipmapsGenerated(const FeatureInfo* feature_info, TextureInfo* info);
+  bool MarkMipmapsGenerated(const FeatureInfo* feature_info, TextureInfo* info,
+                            bool cleared);
 
   // Clears any uncleared renderable levels.
   bool ClearRenderableLevels(GLES2Decoder* decoder, TextureInfo* info);
 
   // Clear a specific level.
   bool ClearTextureLevel(
       GLES2Decoder* decoder,TextureInfo* info, GLenum target, GLint level);
 
   // Creates a new texture info.
   TextureInfo* CreateTextureInfo(
@@ skipping 86 matching lines @@
   TextureInfo::Ref default_texture_external_oes_;
   TextureInfo::Ref default_texture_rectangle_arb_;
 
   DISALLOW_COPY_AND_ASSIGN(TextureManager);
 };
 
 }  // namespace gles2
 }  // namespace gpu
 
 #endif  // GPU_COMMAND_BUFFER_SERVICE_TEXTURE_MANAGER_H_