PCL学习心得

(

pcd_write_test

$${

PCL_COMMON_LIBRARIES

}$${

PC

L_IO_LIBRARIES

}

)

The explanation

cmake_mi nimum_required

(

VERSION2.6FAT AL_ERROR

)

This is mandatory

（强制的）

for cmake, and since we are making very basic project we don’t

need features from cmake 2.8 or higher.

project

(

MY_GRAND_PROJECT

)

This line names your project and sets some useful cmake variables such as those to refer to

the source directory (MY_GRAND_PROJECT_SOURCE_DIR) and the directory from which

you are invoking cmake (MY_GRAND_PROJECT_BINARY_DIR).

find_pac kage

(

PCL1.3REQUIREDCOMPONENT Scommonio

)

We are requesting to find the PCL package at minimum version 1.3. We also says that it

is

REQUIRED

meaning that cmake will fail gracefully if it can’t be found. As PCL is modular

（模

块化的）

one can request:

?

?

?

only one component

（成分）

: find_package(PCL 1.3 REQUIRED COMPONENTS io)

several: find_package(PCL 1.3 REQUIRED COMPONENTS io common)

all existing: find_package(PCL 1.3 REQUIRED)

include_ directories

(

$${

PCL _INCLUDE_DIRS

}

)

l ink_directories

(

$${

PCL_LIBRARY_DIRS

}

)

< br>add_definitions

(

$${

PCL_DEFINITIONS

}

)

When PCL is found, several related variables are set:

?

?

?

?

?

?

PCL_FOUND

: set to 1 if PCL is found, otherwise unset

PCL_INCLUDE_DIRS

: set to the paths to PCL installed headers and the dependency

headers

PCL_LIBRARIES

: set to the file names of the built and installed PCL libraries

PCL_LIBRARY_DIRS

: set to the paths to where PCL libraries and 3rd party

dependencies reside

PCL_VERSION

: the version of the found PCL

PCL_COMPONENTS

: lists all available components

?

PCL_DEFINITIONS

: lists the needed preprocessor definitions and compiler flags

To let cmake know about external headers you include in your project, one needs to

use

include_directories()

macro

（宏）

. In our case

PCL_INCLUDE_DIRS

, contains exactly

what we need, thus we ask cmake to search the paths it contains for a header potentially

included.

add_ex ecutable

（可执行）

(

pcd _write_testpcd_

)

Here, we tell cmake that we are trying to make an executable file

named

pcd_write_test

from one single source file

pcd_

. CMake will take care of

the suffix (

.exe

on Windows platform and blank on UNIX) and the permissions.

target_link_libraries

(

pcd_w rite_test

$${

PCL_COMMON_LIBRAR IES

}$${

PCL_IO_LIBRARIE

S

}

)

The executable we are building makes call to PCL functions. So far, we have only included the

PCL headers so the compilers knows about the methods we are calling. We need also to make

the linker knows about the libraries we are linking against. As said before the, PCL found

libraries are refered to using

PCL_LIBRARIES

variable, all that remains is to trigger the link

operation which we do calling

target_link_libraries()

macro. uses a

CMake special feature named

EXPORT

which allows for using others’ projects targets as if you

built them yourself. When you are using such targets they are called

imported targets

and

acts just like anyother target.

Add the following lines to your file:

cmake_minimum_required

(