kc3-lang/angle/src/libANGLE/renderer/gl/BufferGL.cpp

• Show log

  Commit

• Hash : 90a96efc
  Author :
  Date : 2016-01-27T14:53:36
  

  Allow BufferGL to function without being able to map buffers for read.
  
  Reading back buffer data is required for index range validation but
  without glMapBufferRange it is not possible to read back buffer data on
  OpenGL ES.  To work around this, keep a shadow copy of the buffer data
  when this function is not available.
  
  BUG=angleproject:1145
  
  Change-Id: I8e9b3b174574316d3af0022bd29c7d9c96d168c3
  Reviewed-on: https://chromium-review.googlesource.com/324092
  Reviewed-by: Corentin Wallez <cwallez@chromium.org>
  Commit-Queue: Geoff Lang <geofflang@chromium.org>
  

Download

• src/libANGLE/renderer/gl/BufferGL.cpp

• //
  // Copyright 2015 The ANGLE Project Authors. All rights reserved.
  // Use of this source code is governed by a BSD-style license that can be
  // found in the LICENSE file.
  //
  
  // BufferGL.cpp: Implements the class methods for BufferGL.
  
  #include "libANGLE/renderer/gl/BufferGL.h"
  
  #include "common/debug.h"
  #include "common/utilities.h"
  #include "libANGLE/angletypes.h"
  #include "libANGLE/formatutils.h"
  #include "libANGLE/renderer/gl/FunctionsGL.h"
  #include "libANGLE/renderer/gl/StateManagerGL.h"
  #include "libANGLE/renderer/gl/renderergl_utils.h"
  
  namespace rx
  {
  
  // Use the GL_COPY_READ_BUFFER binding when two buffers need to be bound simultaneously.
  // GL_ELEMENT_ARRAY_BUFFER is supported on more versions but can modify the state of the currently
  // bound VAO.  Two simultaneous buffer bindings are only needed for glCopyBufferSubData which also
  // adds the GL_COPY_READ_BUFFER binding.
  static const GLenum SourceBufferOperationTarget = GL_COPY_READ_BUFFER;
  
  // Use the GL_ELEMENT_ARRAY_BUFFER binding for most operations since it's available on all
  // supported GL versions and doesn't affect any current state when it changes.
  static const GLenum DestBufferOperationTarget = GL_ARRAY_BUFFER;
  
  BufferGL::BufferGL(const FunctionsGL *functions, StateManagerGL *stateManager)
      : BufferImpl(),
        mIsMapped(false),
        mMapOffset(0),
        mMapSize(0),
        mShadowBufferData(!CanMapBufferForRead(functions)),
        mShadowCopy(),
        mBufferSize(0),
        mFunctions(functions),
        mStateManager(stateManager),
        mBufferID(0)
  {
      ASSERT(mFunctions);
      ASSERT(mStateManager);
  
      mFunctions->genBuffers(1, &mBufferID);
  }
  
  BufferGL::~BufferGL()
  {
      mStateManager->deleteBuffer(mBufferID);
      mBufferID = 0;
  }
  
  gl::Error BufferGL::setData(const void* data, size_t size, GLenum usage)
  {
      mStateManager->bindBuffer(DestBufferOperationTarget, mBufferID);
      mFunctions->bufferData(DestBufferOperationTarget, size, data, usage);
  
      if (mShadowBufferData)
      {
          if (!mShadowCopy.resize(size))
          {
              return gl::Error(GL_OUT_OF_MEMORY, "Failed to resize buffer data shadow copy.");
          }
  
          if (size > 0 && data != nullptr)
          {
              memcpy(mShadowCopy.data(), data, size);
          }
      }
  
      mBufferSize = size;
  
      return gl::Error(GL_NO_ERROR);
  }
  
  gl::Error BufferGL::setSubData(const void* data, size_t size, size_t offset)
  {
      mStateManager->bindBuffer(DestBufferOperationTarget, mBufferID);
      mFunctions->bufferSubData(DestBufferOperationTarget, offset, size, data);
  
      if (mShadowBufferData && size > 0)
      {
          memcpy(mShadowCopy.data() + offset, data, size);
      }
  
      return gl::Error(GL_NO_ERROR);
  }
  
  gl::Error BufferGL::copySubData(BufferImpl* source, GLintptr sourceOffset, GLintptr destOffset, GLsizeiptr size)
  {
      BufferGL *sourceGL = GetAs<BufferGL>(source);
  
      mStateManager->bindBuffer(DestBufferOperationTarget, mBufferID);
      mStateManager->bindBuffer(SourceBufferOperationTarget, sourceGL->getBufferID());
  
      mFunctions->copyBufferSubData(SourceBufferOperationTarget, DestBufferOperationTarget, sourceOffset, destOffset, size);
  
      if (mShadowBufferData && size > 0)
      {
          ASSERT(sourceGL->mShadowBufferData);
          memcpy(mShadowCopy.data() + destOffset, sourceGL->mShadowCopy.data() + sourceOffset, size);
      }
  
      return gl::Error(GL_NO_ERROR);
  }
  
  gl::Error BufferGL::map(GLenum access, GLvoid **mapPtr)
  {
      if (mShadowBufferData)
      {
          *mapPtr = mShadowCopy.data();
      }
      else
      {
          mStateManager->bindBuffer(DestBufferOperationTarget, mBufferID);
          *mapPtr = mFunctions->mapBuffer(DestBufferOperationTarget, access);
      }
  
      mIsMapped = true;
      mMapOffset = 0;
      mMapSize   = mBufferSize;
  
      return gl::Error(GL_NO_ERROR);
  }
  
  gl::Error BufferGL::mapRange(size_t offset, size_t length, GLbitfield access, GLvoid **mapPtr)
  {
      if (mShadowBufferData)
      {
          *mapPtr = mShadowCopy.data() + offset;
      }
      else
      {
          mStateManager->bindBuffer(DestBufferOperationTarget, mBufferID);
          *mapPtr = mFunctions->mapBufferRange(DestBufferOperationTarget, offset, length, access);
      }
  
      mIsMapped = true;
      mMapOffset = offset;
      mMapSize   = length;
  
      return gl::Error(GL_NO_ERROR);
  }
  
  gl::Error BufferGL::unmap(GLboolean *result)
  {
      ASSERT(result);
      ASSERT(mIsMapped);
  
      if (mShadowBufferData)
      {
          mStateManager->bindBuffer(DestBufferOperationTarget, mBufferID);
          mFunctions->bufferSubData(DestBufferOperationTarget, mMapOffset, mMapSize,
                                    mShadowCopy.data() + mMapOffset);
          *result = GL_TRUE;
      }
      else
      {
          mStateManager->bindBuffer(DestBufferOperationTarget, mBufferID);
          *result = mFunctions->unmapBuffer(DestBufferOperationTarget);
      }
  
      mIsMapped = false;
      return gl::Error(GL_NO_ERROR);
  }
  
  gl::Error BufferGL::getIndexRange(GLenum type,
                                    size_t offset,
                                    size_t count,
                                    bool primitiveRestartEnabled,
                                    gl::IndexRange *outRange)
  {
      ASSERT(!mIsMapped);
  
      if (mShadowBufferData)
      {
          *outRange = gl::ComputeIndexRange(type, mShadowCopy.data() + offset, count,
                                            primitiveRestartEnabled);
      }
      else
      {
          mStateManager->bindBuffer(DestBufferOperationTarget, mBufferID);
  
          const gl::Type &typeInfo  = gl::GetTypeInfo(type);
          const uint8_t *bufferData = MapBufferRangeWithFallback(
              mFunctions, DestBufferOperationTarget, offset, count * typeInfo.bytes, GL_MAP_READ_BIT);
          *outRange = gl::ComputeIndexRange(type, bufferData, count, primitiveRestartEnabled);
          mFunctions->unmapBuffer(DestBufferOperationTarget);
      }
  
      return gl::Error(GL_NO_ERROR);
  }
  
  GLuint BufferGL::getBufferID() const
  {
      return mBufferID;
  }
  
  }
  

Download