How to compile Box2D in Linux?

Question

Compiling the Box2d Tesbed is supposed to be simple:

from iforce2d:

Download the Box2D source code archive from here. If you want to use the t

Answer 1

If you have the most recent commit from the Box2D repo checked out, you can restore the original CMake files by running this git command in the repository directory:

git checkout 05ee3c3c22af9ac1e5d88061d0b473f814c8210f^ \
 Box2D/Box2D/Box2DConfig.cmake.in \
 Box2D/Box2D/CMakeLists.txt \
 Box2D/Box2D/UseBox2D.cmake \
 Box2D/CMakeLists.txt \
 Box2D/HelloWorld/CMakeLists.txt \
 Box2D/Testbed/CMakeLists.txt \
 Box2D/glew/CMakeLists.txt \
 Box2D/glfw/CMakeLists.txt

Since Box2D has started using C++11 features since this commit, so you will need to add this line to Box2D/CMakeLists.txt:

set (CMAKE_CXX_STANDARD 11)

If you only want the core library built, you're done; just run the following commands:

mkdir build
cd build
cmake -D BOX2D_BUILD_EXAMPLES=OFF ../Box2D

Testbed

If you want the Testbed, things get a bit more involved. The CMakeLists for Box2D's copy of GLFW seems to be completely broken. Open Box2D/CMakeLists.txt, and find these two lines:

add_subdirectory(glew)
add_subdirectory(glfw)

Replace them with the following. This will cause the build to use your system versions of the libraries, so you will need to have them installed:

find_package(GLEW REQUIRED)
if (GLEW_FOUND)
  include_directories(${GLEW_INCLUDE_DIRS})
  link_libraries(${GLEW_LIBRARIES})
endif()

find_package(PkgConfig REQUIRED)
pkg_search_module(GLFW REQUIRED glfw3)
include_directories(${GLFW_INCLUDE_DIRS})

Open Box2D/Testbed/CMakeLists.txt. At the top of the file, under set(Testbed_Framework_SRCS, remove the 4 lines referring to imgui and RenderGL3. Add the following lines in that section:

../imgui/imgui.h
../imgui/imgui.cpp
../imgui/imgui_draw.cpp
../imgui/imgui_impl_glfw_gl3.cpp

Scroll to the bottom and replace the glew and glfw lines with:

${GLEW_LIBRARIES}
${GLFW_STATIC_LIBRARIES}

Finally replace

file(COPY ../Build/Data DESTINATION ..)

with

file(COPY ./Data DESTINATION .)

At this point, the full library and testbed should be buildable:

mkdir build
cd build
cmake ../Box2D