00001 /* 00002 ----------------------------------------------------------------------------- 00003 This source file is part of OGRE 00004 (Object-oriented Graphics Rendering Engine) 00005 For the latest info, see http://www.ogre3d.org/ 00006 00007 Copyright © 2000-2002 The OGRE Team 00008 Also see acknowledgements in Readme.html 00009 00010 This program is free software; you can redistribute it and/or modify it under 00011 the terms of the GNU Lesser General Public License as published by the Free Software 00012 Foundation; either version 2 of the License, or (at your option) any later 00013 version. 00014 00015 This program is distributed in the hope that it will be useful, but WITHOUT 00016 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS 00017 FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. 00018 00019 You should have received a copy of the GNU Lesser General Public License along with 00020 this program; if not, write to the Free Software Foundation, Inc., 59 Temple 00021 Place - Suite 330, Boston, MA 02111-1307, USA, or go to 00022 http://www.gnu.org/copyleft/lesser.txt. 00023 ----------------------------------------------------------------------------- 00024 */ 00025 #ifndef __HardwareBuffer__ 00026 #define __HardwareBuffer__ 00027 00028 // Precompiler options 00029 #include "OgrePrerequisites.h" 00030 00031 namespace Ogre { 00032 00064 class _OgreExport HardwareBuffer 00065 { 00066 00067 public: 00069 enum Usage 00070 { 00074 HBU_STATIC = 1, 00080 HBU_DYNAMIC = 2, 00087 HBU_WRITE_ONLY = 4, 00089 HBU_STATIC_WRITE_ONLY = 5, 00091 HBU_DYNAMIC_WRITE_ONLY = 6 00092 00093 00094 }; 00096 enum LockOptions 00097 { 00099 HBL_NORMAL, 00104 HBL_DISCARD, 00108 HBL_READ_ONLY, 00112 HBL_NO_OVERWRITE 00113 00114 }; 00115 protected: 00116 size_t mSizeInBytes; 00117 Usage mUsage; 00118 bool mIsLocked; 00119 size_t mLockStart; 00120 size_t mLockSize; 00121 bool mSystemMemory; 00122 bool mUseShadowBuffer; 00123 HardwareBuffer* mpShadowBuffer; 00124 bool mShadowUpdated; 00125 00127 virtual void* lockImpl(size_t offset, size_t length, LockOptions options) = 0; 00129 virtual void unlockImpl(void) = 0; 00130 00131 public: 00133 HardwareBuffer(Usage usage, bool systemMemory, bool useShadowBuffer) 00134 : mUsage(usage), mIsLocked(false), mSystemMemory(systemMemory), 00135 mUseShadowBuffer(useShadowBuffer), mpShadowBuffer(NULL), mShadowUpdated(false) {} 00136 virtual ~HardwareBuffer() {} 00143 virtual void* lock(size_t offset, size_t length, LockOptions options) 00144 { 00145 assert(!isLocked() && "Cannot lock this buffer, it is already locked!"); 00146 void* ret; 00147 if (mUseShadowBuffer) 00148 { 00149 if (options != HBL_READ_ONLY) 00150 { 00151 // we have to assume a read / write lock so we use the shadow buffer 00152 // and tag for sync on unlock() 00153 mShadowUpdated = true; 00154 } 00155 00156 ret = mpShadowBuffer->lock(offset, length, options); 00157 } 00158 else 00159 { 00160 // Lock the real buffer if there is no shadow buffer 00161 ret = lockImpl(offset, length, options); 00162 mIsLocked = true; 00163 } 00164 mLockStart = offset; 00165 mLockSize = length; 00166 return ret; 00167 } 00168 00173 void* lock(LockOptions options) 00174 { 00175 return this->lock(0, mSizeInBytes, options); 00176 } 00189 virtual void unlock(void) 00190 { 00191 assert(isLocked() && "Cannot unlock this buffer, it is not locked!"); 00192 00193 // If we used the shadow buffer this time... 00194 if (mUseShadowBuffer && mpShadowBuffer->isLocked()) 00195 { 00196 mpShadowBuffer->unlock(); 00197 // Potentially update the 'real' buffer from the shadow buffer 00198 _updateFromShadow(); 00199 } 00200 else 00201 { 00202 // Otherwise, unlock the real one 00203 unlockImpl(); 00204 mIsLocked = false; 00205 } 00206 00207 } 00208 00215 virtual void readData(size_t offset, size_t length, void* pDest) = 0; 00224 virtual void writeData(size_t offset, size_t length, const void* pSource, 00225 bool discardWholeBuffer = false) = 0; 00226 00237 virtual void copyData(HardwareBuffer& srcBuffer, size_t srcOffset, 00238 size_t dstOffset, size_t length, bool discardWholeBuffer = false) 00239 { 00240 const void *srcData = srcBuffer.lock( 00241 srcOffset, length, HBL_READ_ONLY); 00242 this->writeData(dstOffset, length, srcData, discardWholeBuffer); 00243 srcBuffer.unlock(); 00244 } 00245 00247 virtual void _updateFromShadow(void) 00248 { 00249 if (mUseShadowBuffer && mShadowUpdated) 00250 { 00251 // Do this manually to avoid locking problems 00252 const void *srcData = mpShadowBuffer->lockImpl( 00253 mLockStart, mLockSize, HBL_READ_ONLY); 00254 // Lock with discard if the whole buffer was locked, otherwise normal 00255 LockOptions lockOpt; 00256 if (mLockStart == 0 && mLockSize == mSizeInBytes) 00257 lockOpt = HBL_DISCARD; 00258 else 00259 lockOpt = HBL_NORMAL; 00260 00261 void *destData = this->lockImpl( 00262 mLockStart, mLockSize, lockOpt); 00263 // Copy shadow to real 00264 memcpy(destData, srcData, mLockSize); 00265 this->unlockImpl(); 00266 mpShadowBuffer->unlockImpl(); 00267 mShadowUpdated = false; 00268 } 00269 } 00270 00272 size_t getSizeInBytes(void) const { return mSizeInBytes; } 00274 Usage getUsage(void) const { return mUsage; } 00276 bool isSystemMemory(void) const { return mSystemMemory; } 00278 bool isLocked(void) const { 00279 return mIsLocked || (mUseShadowBuffer && mpShadowBuffer->isLocked()); 00280 } 00281 00282 00283 00284 00285 00286 }; 00287 } 00288 #endif 00289 00290
Copyright © 2002-2003 by The OGRE Team
Last modified Wed Jan 21 00:10:13 2004