Merge pull request #2950 from SunBlack/log2

Use std::log2 instead of custom implementation

features/include/pcl/features/impl/brisk_2d.hpp

@@ -469,8 +469,7 @@ pcl::BRISK2DEstimation<PointInT, PointOutT, KeypointT, IntensityT>::compute (
   kscales.resize (ksize);
 
   // initialize constants
-  static const float log2 = 0.693147180559945f;
-  static const float lb_scalerange = std::log (scalerange_) / (log2);
+  static const float lb_scalerange = std::log2 (scalerange_);
 
   typename std::vector<KeypointT, Eigen::aligned_allocator<KeypointT> >::iterator beginning = keypoints_->points.begin ();
   std::vector<int>::iterator beginningkscales = kscales.begin ();
@@ -479,14 +478,14 @@ pcl::BRISK2DEstimation<PointInT, PointOutT, KeypointT, IntensityT>::compute (
   unsigned int basicscale = 0;
 
   if (!scale_invariance_enabled_)
-    basicscale = std::max (static_cast<int> (float (scales_) / lb_scalerange * (log (1.45f * basic_size_ / (basic_size_06)) / log2) + 0.5f), 0);
+    basicscale = std::max (static_cast<int> (float (scales_) / lb_scalerange * (std::log2 (1.45f * basic_size_ / (basic_size_06))) + 0.5f), 0);
 
   for (size_t k = 0; k < ksize; k++)
   {
     unsigned int scale;
     if (scale_invariance_enabled_)
     {
-      scale = std::max (static_cast<int> (float (scales_) / lb_scalerange * (log (keypoints_->points[k].size / (basic_size_06)) / log2) + 0.5f), 0);
+      scale = std::max (static_cast<int> (float (scales_) / lb_scalerange * (std::log2 (keypoints_->points[k].size / (basic_size_06))) + 0.5f), 0);
       // saturate
       if (scale >= scales_) scale = scales_ - 1;
       kscales[k] = scale;

io/include/pcl/compression/entropy_range_coder.h

@@ -168,10 +168,11 @@ namespace pcl
        * \param n_arg: some value
        * \return binary logarithm (log2) of argument n_arg
        */
+      [[deprecated("use std::log2 instead")]]
       inline double
       Log2 (double n_arg)
       {
-        return log (n_arg) / log (2.0);
+        return std::log2 (n_arg);
       }
 
     private:

io/include/pcl/compression/impl/entropy_range_coder.hpp

@@ -294,7 +294,7 @@ pcl::StaticRangeCoder::encodeIntVectorToStream (std::vector<unsigned int>& input
 
   // calculate amount of bytes per frequency table entry
   uint8_t frequencyTableByteSize = static_cast<uint8_t> (ceil (
-      Log2 (static_cast<double> (cFreqTable_[static_cast<std::size_t> (frequencyTableSize - 1)])) / 8.0));
+      std::log2 (static_cast<double> (cFreqTable_[static_cast<std::size_t> (frequencyTableSize - 1)])) / 8.0));
 
   // write size of frequency table to output stream
   outputByteStream_arg.write (reinterpret_cast<const char*> (&frequencyTableSize), sizeof(frequencyTableSize));

octree/include/pcl/octree/impl/octree2buf_base.hpp

@@ -77,7 +77,7 @@ namespace pcl
 
       // tree depth == amount of bits of maxVoxels
       treeDepth = std::max ((std::min (static_cast<unsigned int> (OctreeKey::maxDepth),
-                                       static_cast<unsigned int> (std::ceil (Log2 (max_voxel_index_arg))))),
+                                       static_cast<unsigned int> (std::ceil (std::log2 (max_voxel_index_arg))))),
                                        static_cast<unsigned int> (0));
 
       // define depthMask_ by setting a single bit to 1 at bit position == tree depth

octree/include/pcl/octree/impl/octree_base.hpp

@@ -79,7 +79,7 @@ namespace pcl
         assert(max_voxel_index_arg>0);
 
         // tree depth == bitlength of maxVoxels
-        tree_depth = std::min (static_cast<unsigned int> (OctreeKey::maxDepth), static_cast<unsigned int> (std::ceil (Log2 (max_voxel_index_arg))));
+        tree_depth = std::min (static_cast<unsigned int> (OctreeKey::maxDepth), static_cast<unsigned int> (std::ceil (std::log2 (max_voxel_index_arg))));
 
         // define depthMask_ by setting a single bit to 1 at bit position == tree depth
         depth_mask_ = (1 << (tree_depth - 1));

octree/include/pcl/octree/impl/octree_pointcloud.hpp

@@ -635,7 +635,7 @@ pcl::octree::OctreePointCloud<PointT, LeafContainerT, BranchContainerT, OctreeT>
 
 
   // tree depth == amount of bits of max_voxels
-  this->octree_depth_ = std::max ((std::min (static_cast<unsigned int> (OctreeKey::maxDepth), static_cast<unsigned int> (ceil (this->Log2 (max_voxels)-minValue)))),
+  this->octree_depth_ = std::max ((std::min (static_cast<unsigned int> (OctreeKey::maxDepth), static_cast<unsigned int> (std::ceil (std::log2 (max_voxels) - minValue)))),
                                   static_cast<unsigned int> (0));
 
   octree_side_len = static_cast<double> (1 << this->octree_depth_) * resolution_;

octree/include/pcl/octree/octree2buf_base.h

@@ -885,9 +885,10 @@ namespace pcl
          * \param n_arg: some value
          * \return binary logarithm (log2) of argument n_arg
          */
+        [[deprecated("use std::log2 instead")]]
         inline double Log2 (double n_arg)
         {
-          return log (n_arg) / log (2.0);
+          return std::log2 (n_arg);
         }
 
         /** \brief Test if octree is able to dynamically change its depth. This is required for adaptive bounding box adjustment.

octree/include/pcl/octree/octree_base.h

@@ -654,10 +654,11 @@ namespace pcl
          * \param n_arg: some value
          * \return binary logarithm (log2) of argument n_arg
          */
+        [[deprecated("use std::log2 instead")]]
         double
         Log2 (double n_arg)
         {
-          return log( n_arg ) / log( 2.0 );
+          return std::log2( n_arg );
         }
 
         /** \brief Test if octree is able to dynamically change its depth. This is required for adaptive bounding box adjustment.

outofcore/include/pcl/outofcore/impl/octree_base.hpp

@@ -734,7 +734,7 @@ namespace pcl
       if (side_length < leaf_resolution)
           return (0);
 
-      boost::uint64_t res = static_cast<boost::uint64_t> (std::ceil (log2f (static_cast<float> (side_length / leaf_resolution))));
+      boost::uint64_t res = static_cast<boost::uint64_t> (std::ceil (std::log2 (side_length / leaf_resolution)));
 
       PCL_DEBUG ("[pcl::outofcore::OutofcoreOctreeBase::calculateDepth] Setting depth to %d\n",res);
       return (res);