text: //
  // Copyright (c) 2008-2018 the Urho3D project.
  //
  // Permission is hereby granted, free of charge, to any person obtaining a copy
  // of this software and associated documentation files (the "Software"), to deal
  // in the Software without restriction, including without limitation the rights
  // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  // copies of the Software, and to permit persons to whom the Software is
  // furnished to do so, subject to the following conditions:
  //
  // The above copyright notice and this permission notice shall be included in
  // all copies or substantial portions of the Software.
  //
  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  // THE SOFTWARE.
  //
  
  #include "../../Precompiled.h"
  
  #include "../../Graphics/Graphics.h"
  #include "../../Graphics/GraphicsImpl.h"
  #include "../../Graphics/VertexBuffer.h"
  #include "../../IO/Log.h"
  
  #include "../../DebugNew.h"
  
  namespace Urho3D
  {
  
  void VertexBuffer::OnDeviceLost()
  {
      // Dynamic buffers are in the default pool and need to be released on device loss
      if (dynamic_)
          Release();
  }
  
  void VertexBuffer::OnDeviceReset()
  {
      // Dynamic buffers are in the default pool and need to be recreated after device reset
      if (dynamic_ || !object_.ptr_)
      {
          Create();
          dataLost_ = !UpdateToGPU();
      }
      else if (dataPending_)
          dataLost_ = !UpdateToGPU();
  
      dataPending_ = false;
  }
  
  void VertexBuffer::Release()
  {
      Unlock();
  
      if (graphics_)
      {
          for (unsigned i = 0; i < MAX_VERTEX_STREAMS; ++i)
          {
              if (graphics_->GetVertexBuffer(i) == this)
                  graphics_->SetVertexBuffer(nullptr);
          }
      }
  
      URHO3D_SAFE_RELEASE(object_.ptr_);
  }
  
  bool VertexBuffer::SetData(const void* data)
  {
      if (!data)
      {
          URHO3D_LOGERROR("Null pointer for vertex buffer data");
          return false;
      }
  
      if (!vertexSize_)
      {
          URHO3D_LOGERROR("Vertex elements not defined, can not set vertex buffer data");
          return false;
      }
  
      if (shadowData_ && data != shadowData_.Get())
          memcpy(shadowData_.Get(), data, vertexCount_ * vertexSize_);
  
      if (object_.ptr_)
      {
          if (graphics_->IsDeviceLost())
          {
              URHO3D_LOGWARNING("Vertex buffer data assignment while device is lost");
              dataPending_ = true;
              return true;
          }
  
          void* hwData = MapBuffer(0, vertexCount_, true);
          if (hwData)
          {
              memcpy(hwData, data, vertexCount_ * vertexSize_);
              UnmapBuffer();
          }
          else
              return false;
      }
  
      dataLost_ = false;
      return true;
  }
  
  bool VertexBuffer::SetDataRange(const void* data, unsigned start, unsigned count, bool discard)
  {
      if (start == 0 && count == vertexCount_)
          return SetData(data);
  
      if (!data)
      {
          URHO3D_LOGERROR("Null pointer for vertex buffer data");
          return false;
      }
  
      if (!vertexSize_)
      {
          URHO3D_LOGERROR("Vertex elements not defined, can not set vertex buffer data");
          return false;
      }
  
      if (start + count > vertexCount_)
      {
          URHO3D_LOGERROR("Illegal range for setting new vertex buffer data");
          return false;
      }
  
      if (!count)
          return true;
  
      if (shadowData_ && shadowData_.Get() + start * vertexSize_ != data)
          memcpy(shadowData_.Get() + start * vertexSize_, data, count * vertexSize_);
  
      if (object_.ptr_)
      {
          if (graphics_->IsDeviceLost())
          {
              URHO3D_LOGWARNING("Vertex buffer data assignment while device is lost");
              dataPending_ = true;
              return true;
          }
  
          void* hwData = MapBuffer(start, count, discard);
          if (hwData)
          {
              memcpy(hwData, data, count * vertexSize_);
              UnmapBuffer();
          }
          else
              return false;
      }
  
      return true;
  }
  
  void* VertexBuffer::Lock(unsigned start, unsigned count, bool discard)
  {
      if (lockState_ != LOCK_NONE)
      {
          URHO3D_LOGERROR("Vertex buffer already locked");
          return nullptr;
      }
  
      if (!vertexSize_)
      {
          URHO3D_LOGERROR("Vertex elements not defined, can not lock vertex buffer");
          return nullptr;
      }
  
      if (start + count > vertexCount_)
      {
          URHO3D_LOGERROR("Illegal range for locking vertex buffer");
          return nullptr;
      }
  
      if (!count)
          return nullptr;
  
      lockStart_ = start;
      lockCount_ = count;
  
      // Because shadow data must be kept in sync, can only lock hardware buffer if not shadowed
      if (object_.ptr_ && !shadowData_ && !graphics_->IsDeviceLost())
          return MapBuffer(start, count, discard);
      else if (shadowData_)
      {
          lockState_ = LOCK_SHADOW;
          return shadowData_.Get() + start * vertexSize_;
      }
      else if (graphics_)
      {
          lockState_ = LOCK_SCRATCH;
          lockScratchData_ = graphics_->ReserveScratchBuffer(count * vertexSize_);
          return lockScratchData_;
      }
      else
          return nullptr;
  }
  
  void VertexBuffer::Unlock()
  {
      switch (lockState_)
      {
      case LOCK_HARDWARE:
          UnmapBuffer();
          break;
  
      case LOCK_SHADOW:
          SetDataRange(shadowData_.Get() + lockStart_ * vertexSize_, lockStart_, lockCount_);
          lockState_ = LOCK_NONE;
          break;
  
      case LOCK_SCRATCH:
          SetDataRange(lockScratchData_, lockStart_, lockCount_);
          if (graphics_)
              graphics_->FreeScratchBuffer(lockScratchData_);
          lockScratchData_ = nullptr;
          lockState_ = LOCK_NONE;
          break;
  
      default: break;
      }
  }
  
  bool VertexBuffer::Create()
  {
      Release();
  
      if (!vertexCount_ || elements_.Empty())
          return true;
  
      if (graphics_)
      {
          if (graphics_->IsDeviceLost())
          {
              URHO3D_LOGWARNING("Vertex buffer creation while device is lost");
              return true;
          }
  
          unsigned pool = dynamic_ ? D3DPOOL_DEFAULT : D3DPOOL_MANAGED;
          unsigned d3dUsage = dynamic_ ? D3DUSAGE_DYNAMIC | D3DUSAGE_WRITEONLY : 0;
  
          IDirect3DDevice9* device = graphics_->GetImpl()->GetDevice();
          HRESULT hr = device->CreateVertexBuffer(
              vertexCount_ * vertexSize_,
              d3dUsage,
              0,
              (D3DPOOL)pool,
              (IDirect3DVertexBuffer9**)&object_.ptr_,
              nullptr);
          if (FAILED(hr))
          {
              URHO3D_SAFE_RELEASE(object_.ptr_);
              URHO3D_LOGD3DERROR("Could not create vertex buffer", hr);
              return false;
          }
      }
  
      return true;
  }
  
  bool VertexBuffer::UpdateToGPU()
  {
      if (object_.ptr_ && shadowData_)
          return SetData(shadowData_.Get());
      else
          return false;
  }
  
  void* VertexBuffer::MapBuffer(unsigned start, unsigned count, bool discard)
  {
      void* hwData = nullptr;
  
      if (object_.ptr_)
      {
          DWORD flags = 0;
  
          if (discard && dynamic_)
              flags = D3DLOCK_DISCARD;
  
          HRESULT hr = ((IDirect3DVertexBuffer9*)object_.ptr_)->Lock(start * vertexSize_, count * vertexSize_, &hwData, flags);
          if (FAILED(hr))
              URHO3D_LOGD3DERROR("Could not lock vertex buffer", hr);
          else
              lockState_ = LOCK_HARDWARE;
      }
  
      return hwData;
  }
  
  void VertexBuffer::UnmapBuffer()
  {
      if (object_.ptr_ && lockState_ == LOCK_HARDWARE)
      {
          ((IDirect3DVertexBuffer9*)object_.ptr_)->Unlock();
          lockState_ = LOCK_NONE;
      }
  }
  
  }
  