寻求基于CMakeLists.txt搭建Drake模拟器C++项目的教程与示例代码

问题描述 #

想尝试新版Drake模拟器，但不想局限在Drake安装目录的examples文件夹下用Bazel构建项目。要开发一个支持多物理模拟器的程序，具备加载模型、设置控制等基础功能，需要通过单个CMakeLists.txt完成构建，但找不到相关示例（哪怕是CMake调用Bazel编译Drake的示例也可以）。尝试在CMake中用find_package(drake REQUIRED)，但找不到drake-config.cmake文件。

我的CMake代码 #

list(APPEND CMAKE_PREFIX_PATH /home/dave/projects/drake/tools/install/libdrake)
message(STATUS "CMAKE_PREFIX_PATH: ${CMAKE_PREFIX_PATH}")
find_package(drake REQUIRED)

错误信息 #

CMake Error at CMakeLists.txt:28 (find_package):
  By not providing "Finddrake.cmake" in CMAKE_MODULE_PATH this project has
  asked CMake to find a package configuration file provided by "drake", but
  CMake did not find one.

  Could not find a package configuration file provided by "drake" with any of
  the following names:

    drakeConfig.cmake
    drake-config.cmake

  Add the installation prefix of "drake" to CMAKE_PREFIX_PATH or set
  "drake_DIR" to a directory containing one of the above files.  If "drake"
  provides a separate development package or SDK, be sure it has been
  installed.

解决方案 #

1. 确认Drake的获取方式 #

• 若你是源码编译Drake，默认不会生成CMake配置文件，需要在编译时加上参数-Ddrake_INSTALL=ON开启安装流程，编译完成后执行make install（或ninja install）把Drake安装到指定目录，此时安装目录下会生成drake-config.cmake。
• 若你是下载预编译二进制包，要确保下载的是包含开发文件的版本，解压后在lib/cmake/drake目录下就能找到drake-config.cmake。

2. 修正CMake前缀路径 #

源码编译并安装后，CMAKE_PREFIX_PATH要指向Drake的安装根目录，不是libdrake子目录。比如安装到/home/dave/drake_install，配置代码如下：

list(APPEND CMAKE_PREFIX_PATH /home/dave/drake_install)
find_package(drake REQUIRED)

或者直接指定drake_DIR指向配置文件所在路径：

set(drake_DIR "/home/dave/drake_install/lib/cmake/drake")
find_package(drake REQUIRED)

3. 基础CMake项目示例 #

以下是最小化的CMake项目示例，可用于编译简单的Drake程序：

cmake_minimum_required(VERSION 3.20)
project(drake_cmake_example)

# 指定Drake配置文件路径
set(drake_DIR "/path/to/drake_install/lib/cmake/drake")
find_package(drake REQUIRED)

# 添加可执行文件
add_executable(hello_drake main.cpp)
# 链接Drake库
target_link_libraries(hello_drake PRIVATE drake::drake)

对应的main.cpp示例（实现模型加载功能）：

#include <drake/multibody/parsing/parser.h>
#include <drake/multibody/plant/multibody_plant.h>
#include <drake/systems/analysis/simulator.h>

int main() {
  // 创建MultibodyPlant实例
  drake::multibody::MultibodyPlant<double> plant(0.0);
  drake::multibody::Parser parser(&plant);
  // 加载URDF模型（替换为你的模型路径）
  parser.AddModelFromFile("path/to/your/model.urdf");
  plant.Finalize();

  // 创建模拟器并初始化
  drake::systems::Simulator<double> simulator(plant);
  simulator.Initialize();
  std::cout << "模型加载成功！" << std::endl;

  return 0;
}

4. CMake调用Bazel编译Drake（可选） #

如果不想单独安装Drake，也可以在CMake中直接调用Bazel构建Drake目标，示例如下：

cmake_minimum_required(VERSION 3.20)
project(drake_bazel_cmake)

# 调用Bazel构建Drake核心库
add_custom_target(drake_build ALL
  COMMAND bazel build //:drake
  WORKING_DIRECTORY /home/dave/projects/drake
)

# 添加可执行文件
add_executable(hello_drake main.cpp)
# 依赖Bazel构建的Drake目标
add_dependencies(hello_drake drake_build)

# 设置包含目录和链接库
target_include_directories(hello_drake PRIVATE
  /home/dave/projects/drake/bazel-bin
  /home/dave/projects/drake
)
target_link_libraries(hello_drake PRIVATE
  /home/dave/projects/drake/bazel-bin/libdrake.a
  # 需额外添加Drake的依赖库（如Eigen、Bullet等），需根据实际情况补充
)

注：这种方式需要手动处理所有依赖库，配置繁琐，优先推荐使用安装后的CMake配置方式。

内容的提问来源于stack exchange，提问作者DMackRus