1 2 /* 3 * Copyright 2014 Google Inc. 4 * 5 * Use of this source code is governed by a BSD-style license that can be 6 * found in the LICENSE file. 7 */ 8 9 #ifndef GrGLNameAllocator_DEFINED 10 #define GrGLNameAllocator_DEFINED 11 12 #include "SkRefCnt.h" 13 #include "gl/GrGLFunctions.h" 14 15 /** 16 * This class assumes ownership of an explicit range of OpenGL object names and 17 * manages allocations within that range. This allows the app to generate new 18 * objects on the client side without making round trips to the GL server. 19 */ 20 class GrGLNameAllocator { 21 public: 22 /** 23 * Constructs a name allocator that produces names within the explicit 24 * half-open range [firstName, end). Note that the caller will most likely 25 * need to call glGen* beforehand to reserve a range within the GL driver, 26 * and then invoke this constructor with that range. 27 * 28 * @param firstName The first name in the range owned by this class. Must be 29 greater than zero. 30 * @param endName The first past-the-end name beyond the range owned by 31 this class. Must be >= firstName. 32 */ 33 GrGLNameAllocator(GrGLuint firstName, GrGLuint endName); 34 35 /** 36 * Destructs the name allocator. The caller is responsible for calling the 37 * appropriate glDelete* on the range if necessary. 38 */ 39 ~GrGLNameAllocator(); 40 41 /** 42 * Return the beginning of this class's range. 43 * 44 * @return The first name in the range owned by this class. 45 */ firstName()46 GrGLuint firstName() const { return fFirstName; } 47 48 /** 49 * Return the end of this class's range. Note that endName() is not owned by 50 * this class. 51 * 52 * @return One plus the final name in the range owned by this class. 53 */ endName()54 GrGLuint endName() const { return fEndName; } 55 56 /** 57 * Allocate an OpenGL object name from within this class's range. 58 * 59 * @return The name if one was available, 60 0 if all the names in the range were already in use. 61 */ 62 GrGLuint allocateName(); 63 64 /** 65 * Free an OpenGL object name, allowing it to be returned by a future call 66 * to allocateName(). Note that the caller should most likely redefine the 67 * object as empty to deallocate any underlying GPU memory before calling 68 * this method (but not call glDelete*, since that would free up the name 69 * within the driver itself). 70 * 71 * @param name The object name to free. Not-allocated names are silently 72 * ignored the same way they are in the OpenGL spec. 73 */ 74 void free(GrGLuint name); 75 76 private: 77 class SparseNameRange; 78 class SparseNameTree; 79 class ContiguousNameRange; 80 81 const GrGLuint fFirstName; 82 const GrGLuint fEndName; 83 SkAutoTUnref<SparseNameRange> fAllocatedNames; 84 }; 85 86 #endif 87