TSDF学习：pcl::gpu::TsdfVolume Class Reference

http://docs.pointclouds.org/trunk/classpcl_1_1gpu_1_1_tsdf_volume.html

Public Member Functions
	TsdfVolume (const Eigen::Vector3i &resolution)
	Constructor. More... 构造函数
void	setSize (const Eigen::Vector3f &size)
	Sets Tsdf volume size for each dimension. More... 设置Tsdf 立方体在X、Y、Z方向的大小，单位m
void	setTsdfTruncDist (float distance)
	Sets Tsdf truncation distance. More... 设置Tsdf 截断距离，其值必须大于 2 * volume_voxel_size
DeviceArray2D< int >	data () const
	Returns tsdf volume container that point to data in GPU memory. More...
const Eigen::Vector3f &	getSize () const
	Returns volume size in meters. More... 返回体积大小，单位m
const Eigen::Vector3i &	getResolution () const
	Returns volume resolution. More... 返回体素在X、Y、Z方向的个数
const Eigen::Vector3f	getVoxelSize () const
	Returns volume voxel size in meters. More... 返回体素大小，单位m
float	getTsdfTruncDist () const
	Returns tsdf truncation distance in meters. More... 返回截断距离
void	reset ()
	Resets tsdf volume data to uninitialized state. More...
void	fetchCloudHost (PointCloud< PointType > &cloud, bool connected26=false) const
	Generates cloud using CPU (downloads volumetric representation to CPU memory) More...
DeviceArray< PointType >	fetchCloud (DeviceArray< PointType > &cloud_buffer) const
	Generates cloud using GPU in connected6 mode only. More...
void	fetchNormals (const DeviceArray< PointType > &cloud, DeviceArray< PointType > &normals) const
	Computes normals as gradient of tsdf for given points. More...
void	fetchNormals (const DeviceArray< PointType > &cloud, DeviceArray< NormalType > &normals) const
	Computes normals as gradient of tsdf for given points. More...
void	downloadTsdf (std::vector< float > &tsdf) const
	Downloads tsdf volume from GPU memory. More... [out] tsdf Array with tsdf values. if volume resolution is 512x512x512, so for voxel (x,y,z) tsdf value can be retrieved as volume[512*512*z + 512*y + x];
void	downloadTsdfAndWeighs (std::vector< float > &tsdf, std::vector< short > &weights) const
	Downloads TSDF volume and according voxel weights from GPU memory. More... [out] tsdf Array with tsdf values. if volume resolution is 512x512x512, so for voxel (x,y,z) tsdf value can be retrieved as volume[512*512*z + 512*y + x]; [out] weights Array with tsdf voxel weights. Same size and access index as for tsdf. A weight of 0 indicates the voxel was never used.

 如图所示：

TSDF立方体的边长为3m；

分辨率可为32x32x32，64x64x64，128x128x128，256x256x256，512x512x512；

如每个坐标轴的体素数量设为512，则每个体素的边长为3/512=0.00585938m