Compositor: Constant folding

Currently there is no clear way to know if an operation is constant
(i.e. when all rendered pixels have same values). Operations may 
need to get constant input values before rendering to determine 
their resolution or areas of interest. This is the case of scale, rotate
and translate operations. Only "set operations" are  known as 
constant but many more are constant when all their inputs are so.
Such cases can be optimized by only rendering one pixel.

Current solution for tiled implementation is to get first pixel
from input. This works for root execution groups, others
need previous groups to be rendered.

On full frame implementation this is not possible, because buffers
are created on rendering to reduce peak memory and there is
no per pixel calls.

This patch evaluates all operations that are constant into primitive
operations (Value/Vector/Color) before determining resolutions.

Reviewed By: jbakker

Differential Revision: https://developer.blender.org/D11490

source/blender/compositor/CMakeLists.txt

@@ -59,6 +59,8 @@ set(SRC
   intern/COM_ChunkOrderHotspot.h
   intern/COM_CompositorContext.cc
   intern/COM_CompositorContext.h
+  intern/COM_ConstantFolder.cc
+  intern/COM_ConstantFolder.h
   intern/COM_Converter.cc
   intern/COM_Converter.h
   intern/COM_Debug.cc
@@ -450,6 +452,8 @@ set(SRC
   operations/COM_MixOperation.h
   operations/COM_ReadBufferOperation.cc
   operations/COM_ReadBufferOperation.h
+  operations/COM_ConstantOperation.cc
+  operations/COM_ConstantOperation.h
   operations/COM_SetColorOperation.cc
   operations/COM_SetColorOperation.h
   operations/COM_SetValueOperation.cc

source/blender/compositor/intern/COM_BufferOperation.cc

@@ -31,6 +31,13 @@ BufferOperation::BufferOperation(MemoryBuffer *buffer, DataType data_type)
   resolution[1] = buffer->getHeight();
   setResolution(resolution);
   addOutputSocket(data_type);
+  flags.is_constant_operation = buffer_->is_a_single_elem();
+}
+
+const float *BufferOperation::get_constant_elem()
+{
+  BLI_assert(buffer_->is_a_single_elem());
+  return buffer_->getBuffer();
 }
 
 void *BufferOperation::initializeTileData(rcti * /*rect*/)

source/blender/compositor/intern/COM_BufferOperation.h

@@ -18,11 +18,11 @@
 
 #pragma once
 
-#include "COM_NodeOperation.h"
+#include "COM_ConstantOperation.h"
 
 namespace blender::compositor {
 
-class BufferOperation : public NodeOperation {
+class BufferOperation : public ConstantOperation {
  private:
   MemoryBuffer *buffer_;
   MemoryBuffer *inflated_buffer_;
@@ -30,6 +30,7 @@ class BufferOperation : public NodeOperation {
  public:
   BufferOperation(MemoryBuffer *buffer, DataType data_type);
 
+  const float *get_constant_elem() override;
   void *initializeTileData(rcti *rect) override;
   void deinitExecution() override;
   void executePixelSampled(float output[4], float x, float y, PixelSampler sampler) override;

source/blender/compositor/intern/COM_ConstantFolder.cc

@@ -0,0 +1,186 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * Copyright 2021, Blender Foundation.
+ */
+
+#include "BLI_rect.h"
+
+#include "COM_ConstantFolder.h"
+#include "COM_ConstantOperation.h"
+#include "COM_SetColorOperation.h"
+#include "COM_SetValueOperation.h"
+#include "COM_SetVectorOperation.h"
+
+namespace blender::compositor {
+
+using Link = NodeOperationBuilder::Link;
+
+/**
+ * \param operations_builder: Contains all operations to fold.
+ * \param exec_system: Execution system.
+ */
+ConstantFolder::ConstantFolder(NodeOperationBuilder &operations_builder)
+    : operations_builder_(operations_builder)
+{
+  BLI_rcti_init(&max_area_, INT_MIN, INT_MAX, INT_MIN, INT_MAX);
+  BLI_rcti_init(&first_elem_area_, 0, 1, 0, 1);
+}
+
+static bool is_constant_foldable(NodeOperation *operation)
+{
+  if (operation->get_flags().can_be_constant && !operation->get_flags().is_constant_operation) {
+    for (int i = 0; i < operation->getNumberOfInputSockets(); i++) {
+      if (!operation->get_input_operation(i)->get_flags().is_constant_operation) {
+        return false;
+      }
+    }
+    return true;
+  }
+  return false;
+}
+
+static Vector<NodeOperation *> find_constant_foldable_operations(Span<NodeOperation *> operations)
+{
+  Vector<NodeOperation *> foldable_ops;
+  for (NodeOperation *op : operations) {
+    if (is_constant_foldable(op)) {
+      foldable_ops.append(op);
+    }
+  }
+  return foldable_ops;
+}
+
+static ConstantOperation *create_constant_operation(DataType data_type, const float *constant_elem)
+{
+  switch (data_type) {
+    case DataType::Color: {
+      SetColorOperation *color_op = new SetColorOperation();
+      color_op->setChannels(constant_elem);
+      return color_op;
+    }
+    case DataType::Vector: {
+      SetVectorOperation *vector_op = new SetVectorOperation();
+      vector_op->setVector(constant_elem);
+      return vector_op;
+    }
+    case DataType::Value: {
+      SetValueOperation *value_op = new SetValueOperation();
+      value_op->setValue(*constant_elem);
+      return value_op;
+    }
+    default: {
+      BLI_assert(!"Non implemented data type");
+      return nullptr;
+    }
+  }
+}
+
+ConstantOperation *ConstantFolder::fold_operation(NodeOperation *operation)
+{
+  const DataType data_type = operation->getOutputSocket()->getDataType();
+  MemoryBuffer *fold_buf = create_constant_buffer(data_type);
+  Vector<MemoryBuffer *> input_bufs = get_constant_input_buffers(operation);
+  operation->render(fold_buf, {first_elem_area_}, input_bufs);
+
+  ConstantOperation *constant_op = create_constant_operation(data_type, fold_buf->getBuffer());
+  operations_builder_.replace_operation_with_constant(operation, constant_op);
+  constant_buffers_.add_new(constant_op, fold_buf);
+  return constant_op;
+}
+
+MemoryBuffer *ConstantFolder::create_constant_buffer(const DataType data_type)
+{
+  /* Create a single elem buffer with maximum area possible so readers can read any coordinate
+   * returning always same element. */
+  return new MemoryBuffer(data_type, max_area_, true);
+}
+
+Vector<MemoryBuffer *> ConstantFolder::get_constant_input_buffers(NodeOperation *operation)
+{
+  const int num_inputs = operation->getNumberOfInputSockets();
+  Vector<MemoryBuffer *> inputs_bufs(num_inputs);
+  for (int i = 0; i < num_inputs; i++) {
+    BLI_assert(operation->get_input_operation(i)->get_flags().is_constant_operation);
+    ConstantOperation *constant_op = static_cast<ConstantOperation *>(
+        operation->get_input_operation(i));
+    MemoryBuffer *constant_buf = constant_buffers_.lookup_or_add_cb(constant_op, [=] {
+      MemoryBuffer *buf = create_constant_buffer(constant_op->getOutputSocket()->getDataType());
+      constant_op->render(buf, {first_elem_area_}, {});
+      return buf;
+    });
+    inputs_bufs[i] = constant_buf;
+  }
+  return inputs_bufs;
+}
+
+/** Returns constant operations resulted from folded operations. */
+Vector<ConstantOperation *> ConstantFolder::try_fold_operations(Span<NodeOperation *> operations)
+{
+  Vector<NodeOperation *> foldable_ops = find_constant_foldable_operations(operations);
+  if (foldable_ops.size() == 0) {
+    return Vector<ConstantOperation *>();
+  }
+
+  Vector<ConstantOperation *> new_folds;
+  for (NodeOperation *op : foldable_ops) {
+    ConstantOperation *constant_op = fold_operation(op);
+    new_folds.append(constant_op);
+  }
+  return new_folds;
+}
+
+/**
+ * Evaluate operations with constant elements into primitive constant operations.
+ */
+int ConstantFolder::fold_operations()
+{
+  Vector<ConstantOperation *> last_folds = try_fold_operations(
+      operations_builder_.get_operations());
+  int folds_count = last_folds.size();
+  while (last_folds.size() > 0) {
+    Vector<NodeOperation *> ops_to_fold;
+    for (ConstantOperation *fold : last_folds) {
+      get_operation_output_operations(fold, ops_to_fold);
+    }
+    last_folds = try_fold_operations(ops_to_fold);
+    folds_count += last_folds.size();
+  }
+
+  delete_constant_buffers();
+
+  return folds_count;
+}
+
+void ConstantFolder::delete_constant_buffers()
+{
+  for (MemoryBuffer *buf : constant_buffers_.values()) {
+    delete buf;
+  }
+  constant_buffers_.clear();
+}
+
+void ConstantFolder::get_operation_output_operations(NodeOperation *operation,
+                                                     Vector<NodeOperation *> &r_outputs)
+{
+  const Vector<Link> &links = operations_builder_.get_links();
+  for (const Link &link : links) {
+    if (&link.from()->getOperation() == operation) {
+      r_outputs.append(&link.to()->getOperation());
+    }
+  }
+}
+
+}  // namespace blender::compositor

source/blender/compositor/intern/COM_ConstantFolder.h

@@ -0,0 +1,64 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * Copyright 2021, Blender Foundation.
+ */
+
+#pragma once
+
+#include "BLI_map.hh"
+#include "BLI_set.hh"
+#include "BLI_vector.hh"
+
+#include "COM_NodeOperationBuilder.h"
+#include "COM_defines.h"
+
+namespace blender::compositor {
+
+class NodeOperation;
+class ConstantOperation;
+class MemoryBuffer;
+
+/**
+ * Evaluates all operations with constant elements into primitive constant operations
+ * (Value/Vector/Color).
+ */
+class ConstantFolder {
+ private:
+  NodeOperationBuilder &operations_builder_;
+
+  /** Constant operations buffers. */
+  Map<ConstantOperation *, MemoryBuffer *> constant_buffers_;
+
+  rcti max_area_;
+  rcti first_elem_area_;
+
+ public:
+  ConstantFolder(NodeOperationBuilder &operations_builder);
+  int fold_operations();
+
+ private:
+  Vector<ConstantOperation *> try_fold_operations(Span<NodeOperation *> operations);
+  ConstantOperation *fold_operation(NodeOperation *operation);
+
+  MemoryBuffer *create_constant_buffer(DataType data_type);
+  Vector<MemoryBuffer *> get_constant_input_buffers(NodeOperation *operation);
+  void delete_constant_buffers();
+
+  void get_operation_output_operations(NodeOperation *operation,
+                                       Vector<NodeOperation *> &r_outputs);
+};
+
+}  // namespace blender::compositor

source/blender/compositor/intern/COM_Debug.cc

@@ -401,7 +401,7 @@ bool DebugInfo::graphviz_system(const ExecutionSystem *system, char *str, int ma
   return (len < maxlen);
 }
 
-void DebugInfo::graphviz(const ExecutionSystem *system)
+void DebugInfo::graphviz(const ExecutionSystem *system, StringRefNull name)
 {
   if (!COM_EXPORT_GRAPHVIZ) {
     return;
@@ -411,7 +411,12 @@ void DebugInfo::graphviz(const ExecutionSystem *system)
     char basename[FILE_MAX];
     char filename[FILE_MAX];
 
-    BLI_snprintf(basename, sizeof(basename), "compositor_%d.dot", m_file_index);
+    if (name.is_empty()) {
+      BLI_snprintf(basename, sizeof(basename), "compositor_%d.dot", m_file_index);
+    }
+    else {
+      BLI_strncpy(basename, (name + ".dot").c_str(), sizeof(basename));
+    }
     BLI_join_dirfile(filename, sizeof(filename), BKE_tempdir_session(), basename);
     m_file_index++;
 

source/blender/compositor/intern/COM_Debug.h

@@ -116,7 +116,7 @@ class DebugInfo {
     }
   };
 
-  static void graphviz(const ExecutionSystem *system);
+  static void graphviz(const ExecutionSystem *system, StringRefNull name = "");
 
  protected:
   static int graphviz_operation(const ExecutionSystem *system,

source/blender/compositor/intern/COM_FullFrameExecutionModel.cc

@@ -60,7 +60,7 @@ void FullFrameExecutionModel::execute(ExecutionSystem &exec_system)
   const bNodeTree *node_tree = this->context_.getbNodeTree();
   node_tree->stats_draw(node_tree->sdh, TIP_("Compositing | Initializing execution"));
 
-  DebugInfo::graphviz(&exec_system);
+  DebugInfo::graphviz(&exec_system, "compositor_prior_rendering");
 
   determine_areas_to_render_and_reads();
   render_operations();
@@ -101,9 +101,7 @@ MemoryBuffer *FullFrameExecutionModel::create_operation_buffer(NodeOperation *op
   BLI_rcti_init(&op_rect, 0, op->getWidth(), 0, op->getHeight());
 
   const DataType data_type = op->getOutputSocket(0)->getDataType();
-  /* TODO: We should check if the operation is constant instead of is_set_operation. Finding a way
-   * to know if an operation is constant has to be implemented yet. */
-  const bool is_a_single_elem = op->get_flags().is_set_operation;
+  const bool is_a_single_elem = op->get_flags().is_constant_operation;
   return new MemoryBuffer(data_type, op_rect, is_a_single_elem);
 }
 

source/blender/compositor/intern/COM_NodeOperation.cc

@@ -441,6 +441,12 @@ std::ostream &operator<<(std::ostream &os, const NodeOperationFlags &node_operat
   if (node_operation_flags.is_fullframe_operation) {
     os << "full_frame,";
   }
+  if (node_operation_flags.is_constant_operation) {
+    os << "contant_operation,";
+  }
+  if (node_operation_flags.can_be_constant) {
+    os << "can_be_constant,";
+  }
 
   return os;
 }

source/blender/compositor/intern/COM_NodeOperation.h

@@ -221,6 +221,7 @@ struct NodeOperationFlags {
 
   /**
    * Is this a set operation (value, color, vector).
+   * TODO: To be replaced by is_constant_operation flag once tiled implementation is removed.
    */
   bool is_set_operation : 1;
   bool is_write_buffer_operation : 1;
@@ -242,6 +243,17 @@ struct NodeOperationFlags {
    */
   bool is_fullframe_operation : 1;
 
+  /**
+   * Whether operation is a primitive constant operation (Color/Vector/Value).
+   */
+  bool is_constant_operation : 1;
+
+  /**
+   * Whether operation have constant elements/pixels values when all its inputs are constant
+   * operations.
+   */
+  bool can_be_constant : 1;
+
   NodeOperationFlags()
   {
     complex = false;
@@ -258,6 +270,8 @@ struct NodeOperationFlags {
     is_preview_operation = false;
     use_datatype_conversion = true;
     is_fullframe_operation = false;
+    is_constant_operation = false;
+    can_be_constant = false;
   }
 };
 

source/blender/compositor/intern/COM_NodeOperationBuilder.cc

@@ -36,6 +36,7 @@
 #include "COM_ViewerOperation.h"
 #include "COM_WriteBufferOperation.h"
 
+#include "COM_ConstantFolder.h"
 #include "COM_NodeOperationBuilder.h" /* own include */
 
 namespace blender::compositor {
@@ -97,6 +98,15 @@ void NodeOperationBuilder::convertToOperations(ExecutionSystem *system)
 
   add_datatype_conversions();
 
+  if (m_context->get_execution_model() == eExecutionModel::FullFrame) {
+    /* Copy operations to system. Needed for graphviz. */
+    system->set_operations(m_operations, {});
+
+    DebugInfo::graphviz(system, "compositor_prior_folding");
+    ConstantFolder folder(*this);
+    folder.fold_operations();
+  }
+
   determineResolutions();
 
   if (m_context->get_execution_model() == eExecutionModel::Tiled) {
@@ -132,6 +142,28 @@ void NodeOperationBuilder::addOperation(NodeOperation *operation)
   operation->set_execution_model(m_context->get_execution_model());
 }
 
+void NodeOperationBuilder::replace_operation_with_constant(NodeOperation *operation,
+                                                           ConstantOperation *constant_operation)
+{
+  BLI_assert(constant_operation->getNumberOfInputSockets() == 0);
+  int i = 0;
+  while (i < m_links.size()) {
+    Link &link = m_links[i];
+    if (&link.to()->getOperation() == operation) {
+      link.to()->setLink(nullptr);
+      m_links.remove(i);
+      continue;
+    }
+
+    if (&link.from()->getOperation() == operation) {
+      link.to()->setLink(constant_operation->getOutputSocket());
+      m_links[i] = Link(constant_operation->getOutputSocket(), link.to());
+    }
+    i++;
+  }
+  addOperation(constant_operation);
+}
+
 void NodeOperationBuilder::mapInputSocket(NodeInput *node_socket,
                                           NodeOperationInput *operation_socket)
 {

source/blender/compositor/intern/COM_NodeOperationBuilder.h

@@ -41,6 +41,7 @@ class NodeOperationOutput;
 class PreviewOperation;
 class WriteBufferOperation;
 class ViewerOperation;
+class ConstantOperation;
 
 class NodeOperationBuilder {
  public:
@@ -96,6 +97,8 @@ class NodeOperationBuilder {
   void convertToOperations(ExecutionSystem *system);
 
   void addOperation(NodeOperation *operation);
+  void replace_operation_with_constant(NodeOperation *operation,
+                                       ConstantOperation *constant_operation);
 
   /** Map input socket of the current node to an operation socket */
   void mapInputSocket(NodeInput *node_socket, NodeOperationInput *operation_socket);

source/blender/compositor/operations/COM_ConstantOperation.cc

@@ -0,0 +1,28 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * Copyright 2021, Blender Foundation.
+ */
+
+#include "COM_ConstantOperation.h"
+
+namespace blender::compositor {
+
+ConstantOperation::ConstantOperation()
+{
+  flags.is_constant_operation = true;
+}
+
+}  // namespace blender::compositor

source/blender/compositor/operations/COM_ConstantOperation.h

@@ -0,0 +1,36 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * Copyright 2021, Blender Foundation.
+ */
+
+#pragma once
+
+#include "COM_NodeOperation.h"
+
+namespace blender::compositor {
+
+/**
+ * Base class for primitive constant operations (Color/Vector/Value). The rest of operations that
+ * can be constant are evaluated into primitives during constant folding.
+ */
+class ConstantOperation : public NodeOperation {
+ public:
+  ConstantOperation();
+
+  virtual const float *get_constant_elem() = 0;
+};
+
+}  // namespace blender::compositor

source/blender/compositor/operations/COM_SetColorOperation.h

@@ -18,7 +18,7 @@
 
 #pragma once
 
-#include "COM_NodeOperation.h"
+#include "COM_ConstantOperation.h"
 
 namespace blender::compositor {
 
@@ -26,7 +26,7 @@ namespace blender::compositor {
  * this program converts an input color to an output value.
  * it assumes we are in sRGB color space.
  */
-class SetColorOperation : public NodeOperation {
+class SetColorOperation : public ConstantOperation {
  private:
   float m_color[4];
 
@@ -36,6 +36,11 @@ class SetColorOperation : public NodeOperation {
    */
   SetColorOperation();
 
+  const float *get_constant_elem() override
+  {
+    return m_color;
+  }
+
   float getChannel1()
   {
     return this->m_color[0];

source/blender/compositor/operations/COM_SetValueOperation.h

@@ -18,7 +18,7 @@
 
 #pragma once
 
-#include "COM_NodeOperation.h"
+#include "COM_ConstantOperation.h"
 
 namespace blender::compositor {
 
@@ -26,7 +26,7 @@ namespace blender::compositor {
  * this program converts an input color to an output value.
  * it assumes we are in sRGB color space.
  */
-class SetValueOperation : public NodeOperation {
+class SetValueOperation : public ConstantOperation {
  private:
   float m_value;
 
@@ -36,6 +36,11 @@ class SetValueOperation : public NodeOperation {
    */
   SetValueOperation();
 
+  const float *get_constant_elem() override
+  {
+    return &m_value;
+  }
+
   float getValue()
   {
     return this->m_value;

source/blender/compositor/operations/COM_SetVectorOperation.cc

@@ -32,9 +32,9 @@ void SetVectorOperation::executePixelSampled(float output[4],
                                              float /*y*/,
                                              PixelSampler /*sampler*/)
 {
-  output[0] = this->m_x;
-  output[1] = this->m_y;
-  output[2] = this->m_z;
+  output[0] = vector_.x;
+  output[1] = vector_.y;
+  output[2] = vector_.z;
 }
 
 void SetVectorOperation::determineResolution(unsigned int resolution[2],

source/blender/compositor/operations/COM_SetVectorOperation.h

@@ -18,7 +18,7 @@
 
 #pragma once
 
-#include "COM_NodeOperation.h"
+#include "COM_ConstantOperation.h"
 
 namespace blender::compositor {
 
@@ -26,12 +26,14 @@ namespace blender::compositor {
  * this program converts an input color to an output value.
  * it assumes we are in sRGB color space.
  */
-class SetVectorOperation : public NodeOperation {
+class SetVectorOperation : public ConstantOperation {
  private:
-  float m_x;
-  float m_y;
-  float m_z;
-  float m_w;
+  struct {
+    float x;
+    float y;
+    float z;
+    float w;
+  } vector_;
 
  public:
   /**
@@ -39,37 +41,42 @@ class SetVectorOperation : public NodeOperation {
    */
   SetVectorOperation();
 
+  const float *get_constant_elem() override
+  {
+    return reinterpret_cast<float *>(&vector_);
+  }
+
   float getX()
   {
-    return this->m_x;
+    return vector_.x;
   }
   void setX(float value)
   {
-    this->m_x = value;
+    vector_.x = value;
   }
   float getY()
   {
-    return this->m_y;
+    return vector_.y;
   }
   void setY(float value)
   {
-    this->m_y = value;
+    vector_.y = value;
   }
   float getZ()
   {
-    return this->m_z;
+    return vector_.z;
   }
   void setZ(float value)
   {
-    this->m_z = value;
+    vector_.z = value;
   }
   float getW()
   {
-    return this->m_w;
+    return vector_.w;
   }
   void setW(float value)
   {
-    this->m_w = value;
+    vector_.w = value;
   }
 
   /**