text: //
  //  GLReshape.cpp
  //  MNN
  //
  //  Created by MNN on 2019/01/31.
  //  Copyright © 2018, Alibaba Group Holding Limited
  //
  
  #include "backend/opengl/GLReshape.hpp"
  #include <sstream>
  #include "AllShader.hpp"
  #include "backend/opengl/GLBackend.hpp"
  #include "core/Macro.h"
  #include "core/TensorUtils.hpp"
  
  namespace MNN {
  namespace OpenGL {
  GLReshape::GLReshape(const std::vector<Tensor *> &inputs, const Op *op, Backend *bn) : Execution(bn) {
      mDimType = op->main_as_Reshape()->dimType();
  }
  
  GLReshape::~GLReshape() {
  
  }
  
  ErrorCode GLReshape::onResize(const std::vector<Tensor *> &inputs, const std::vector<Tensor *> &outputs) {
      std::vector<std::string> prefix;
      setLocalSize(prefix, mLocalSize, 8, 8, 1);
      mTempBuffer.reset(new GLSSBOBuffer(inputs[0]->size()));
      auto input = inputs[0];
  
      if (mDimType == MNN_DATA_FORMAT_NCHW) {
          mSrcProgram = ((GLBackend *)backend())->getProgram("src", glsl_image_to_nchw_buffer_glsl, prefix);
          mDstProgram = ((GLBackend *)backend())->getProgram("dst", glsl_nchw_buffer_to_image_glsl, prefix);
      }else{
          mSrcProgram = ((GLBackend *)backend())->getProgram("src", glsl_image_to_nhwc_buffer_glsl, prefix);
          mDstProgram = ((GLBackend *)backend())->getProgram("dst", glsl_nhwc_buffer_to_image_glsl, prefix);
      }
  
      return NO_ERROR;
  }
  
  ErrorCode GLReshape::onExecute(const std::vector<Tensor *> &inputs, const std::vector<Tensor *> &outputs) {
      auto input = inputs[0];
      auto output = outputs[0];
  
      std::vector<int> inputShape  = tensorShapeFormat(input);
      std::vector<int> outputShape = tensorShapeFormat(output);
  
      int ib = inputShape.at(0);
      int ih = inputShape.at(1);
      int iw = inputShape.at(2);
      int ic = inputShape.at(3);
      int ic_4 = UP_DIV(ic, 4);
  
      int ob = outputShape.at(0);
      int oh = outputShape.at(1);
      int ow = outputShape.at(2);
      int oc = outputShape.at(3);
      int oc_4 = UP_DIV(oc, 4);
  
      if (mDimType == MNN_DATA_FORMAT_NCHW) {
          //image -> buffer(nchw)
          {
              mSrcProgram->useProgram();
              glBindImageTexture(0, input->deviceId(), 0, GL_TRUE, 0, GL_READ_ONLY, ((GLBackend *)backend())->getTextrueFormat());
              glBindBufferBase(GL_SHADER_STORAGE_BUFFER, 1, mTempBuffer->getId());
              glUniform1i(2, iw);
              glUniform1i(3, ih);
              OPENGL_CHECK_ERROR;
              ((GLBackend *)backend())->compute(UP_DIV(iw, mLocalSize[0]), UP_DIV(ih, mLocalSize[1]), UP_DIV(ic_4, mLocalSize[2]));
              OPENGL_CHECK_ERROR;
          }
          //buffer(nchw) -> image
          {
              mDstProgram->useProgram();
              glBindImageTexture(0, output->deviceId(), 0, GL_TRUE, 0, GL_WRITE_ONLY, ((GLBackend *)backend())->getTextrueFormat());
              glBindBufferBase(GL_SHADER_STORAGE_BUFFER, 1, mTempBuffer->getId());
              glUniform1i(2, ow);
              glUniform1i(3, oh);
              OPENGL_CHECK_ERROR;
              ((GLBackend *)backend())->compute(UP_DIV(ow, mLocalSize[0]), UP_DIV(oh, mLocalSize[1]), UP_DIV(oc_4, mLocalSize[2]));
              OPENGL_CHECK_ERROR;
          }
      }else{
          //image -> buffer(nhwc)
          {
              mSrcProgram->useProgram();
              glBindImageTexture(0, input->deviceId(), 0, GL_TRUE, 0, GL_READ_ONLY, ((GLBackend *)backend())->getTextrueFormat());
              glBindBufferBase(GL_SHADER_STORAGE_BUFFER, 1, mTempBuffer->getId());
              glUniform1i(2, iw);
              glUniform1i(3, ih);
              glUniform1i(4, ic);
              OPENGL_CHECK_ERROR;
              ((GLBackend *)backend())->compute(UP_DIV(iw, mLocalSize[0]), UP_DIV(ih, mLocalSize[1]), UP_DIV(ic_4, mLocalSize[2]));
              OPENGL_CHECK_ERROR;
          }
  
          //buffer -> image
          {
              mDstProgram->useProgram();
              glBindImageTexture(0, output->deviceId(), 0, GL_TRUE, 0, GL_WRITE_ONLY, ((GLBackend *)backend())->getTextrueFormat());
              glBindBufferBase(GL_SHADER_STORAGE_BUFFER, 1, mTempBuffer->getId());
              glUniform1i(2, ow);
              glUniform1i(3, oh);
              glUniform1i(4, oc);
              OPENGL_CHECK_ERROR;
              ((GLBackend *)backend())->compute(UP_DIV(ow, mLocalSize[0]), UP_DIV(oh, mLocalSize[1]), UP_DIV(oc_4, mLocalSize[2]));
              OPENGL_CHECK_ERROR;
          }
      }
  
      return NO_ERROR;
  }
  
  class ReshapeCreator : public GLBackend::Creator {
  public:
      virtual ~ReshapeCreator() = default;
      virtual Execution *onCreate(const std::vector<Tensor *> &inputs, const std::vector<Tensor *> &outputs,
                                  const MNN::Op *op, Backend *backend) const override {
  
          if(inputs[0]->dimensions() == 3 || outputs[0]->dimensions() == 3){
              MNN_PRINT("reshape not support dimensions == 3 \n");
              return nullptr;
          }
          return new GLReshape(inputs, op, backend);
      }
  };
  GLCreatorRegister<ReshapeCreator> __reshape_op(OpType_Reshape);
  } // namespace OpenGL
  } // namespace MNN
  