Static Linking error for Bullet Physics Engine

Development Programming & Scripting C++
1

I’m trying to import the library Bullet physics to unreal engine source.

But I’m having problem with static linking of library, I get this error: unresolved external symbol _DllMainCRTStartup


 Creating makefile for UE4Editor (no existing makefile)
2>  Performing 2 actions (4 in parallel)
2>  [1/2] Link UE4Editor-Engine.dll
2>  [2/2] Link UE4Editor-Bullet.dll
2>LINK : error LNK2001: unresolved external symbol _DllMainCRTStartup
2>D:\WorkSpace\GitHubProjects\UE_4.16\UnrealEngine\Engine\Binaries\Win64\UE4Editor-Bullet.dll : fatal error LNK1120: 1 unresolved externals
2>     Creating library D:\WorkSpace\GitHubProjects\UE_4.16\UnrealEngine\Engine\Intermediate\Build\Win64\UE4Editor\Development\UE4Editor-Engine.suppressed.lib and object D:\WorkSpace\GitHubProjects\UE_4.16\UnrealEngine\Engine\Intermediate\Build\Win64\UE4Editor\Development\UE4Editor-Engine.suppressed.exp
2>ERROR : UBT error : Failed to produce item: D:\WorkSpace\GitHubProjects\UE_4.16\UnrealEngine\Engine\Binaries\Win64\UE4Editor-Bullet.dll

Do you know what cause this error and how to fix it?

What I did
Step 1
I’ve create Bullet VS project using CMake, then I’ve builded it.

Step 2
I’ve copyed either the include and lib directory to “\Engine\Source\ThirdParty\Bullet\build”, created the file Bullet.Build.cs

Bullet.Build.cs


using System.IO;
using System;
using UnrealBuildTool;

public class Bullet : ModuleRules
{

    enum BulletLibraryMode{
        Debug,
        Shipping
    }

    BulletLibraryMode GetPhysXLibraryMode(UnrealTargetConfiguration Config)
    {
        switch (Config)
        {
            case UnrealTargetConfiguration.Shipping:
            case UnrealTargetConfiguration.Test:
                return BulletLibraryMode.Shipping;
            case UnrealTargetConfiguration.Development:
            case UnrealTargetConfiguration.DebugGame:
            case UnrealTargetConfiguration.Unknown:
            case UnrealTargetConfiguration.Debug:
            default:
                return BulletLibraryMode.Debug;
        }
    }

    static string GetBulletLibrarySuffix(BulletLibraryMode Mode){
        switch (Mode){
            case BulletLibraryMode.Debug:
                return "_Debug";
            case BulletLibraryMode.Shipping:
            default:
                return "";
        }
    }

    public Bullet(ReadOnlyTargetRules Target) : base(Target){

        string BulletBaseDir = UEBuildConfiguration.UEThirdPartySourceDirectory + "Bullet/build/";
        string PlatformDir = "";

        bool bSupported = false;
        if (Target.Platform == UnrealTargetPlatform.Win64)
        {
            bSupported = true;
            PlatformDir = "Win64/";
        }
        else if(Target.Platform == UnrealTargetPlatform.Win32)
        {
            bSupported = true;
            PlatformDir = "Win32/";
        }

        if (bSupported)
        {
            BulletBaseDir += PlatformDir;
            string LibraryPath = BulletBaseDir + "lib/";
            string IncludePath = BulletBaseDir + "include/bullet/";
            string Suffix = GetBulletLibrarySuffix(GetPhysXLibraryMode(Target.Configuration));

            PublicIncludePaths.Add(IncludePath);

            // Load libraries

            string] BulletLibs = new string] {
                "Bullet2FileLoader",
                "Bullet3Collision",
                "Bullet3Common",
                "Bullet3Dynamics",
                "Bullet3Geometry",
                "Bullet3OpenCL_clew",
                "BulletCollision",
                "BulletDynamics",
                "BulletInverseDynamics",
                "BulletSoftBody",
                "LinearMath"
            };

            foreach (string Lib in BulletLibs)
            {
                PublicAdditionalLibraries.Add(LibraryPath + Lib + Suffix + ".lib");
            }

        }
    }
}

Step 3
Then I’ve added AddEngineThirdPartyPrivateStaticDependencies(Target, “Bullet”); to Engine.Build.cs

Step 4
After Generating project file using GenerateProjectFiles.bat I’ve builded the engine but I get the error described above.

Do you know what cause this error and how to fix it?

2

I noticed Bullet’s CMake has a rule that force the use of /MT (Multithreaded)


IF (NOT USE_MSVC_RUNTIME_LIBRARY_DLL)
		#We statically link to reduce dependancies
		FOREACH(flag_var CMAKE_CXX_FLAGS CMAKE_CXX_FLAGS_DEBUG CMAKE_CXX_FLAGS_RELEASE CMAKE_CXX_FLAGS_MINSIZEREL CMAKE_CXX_FLAGS_RELWITHDEBINFO CMAKE_C_FLAGS CMAKE_C_FLAGS_DEBUG CMAKE_C_FLAGS_RELEASE CMAKE_C_FLAGS_MINSIZEREL CMAKE_C_FLAGS_RELWITHDEBINFO )
			IF(${flag_var} MATCHES "/MD")
				STRING(REGEX REPLACE "/MD" "/MT" ${flag_var} "${${flag_var}}")
			ENDIF(${flag_var} MATCHES "/MD")
			IF(${flag_var} MATCHES "/MDd")
				STRING(REGEX REPLACE "/MDd" "/MTd" ${flag_var} "${${flag_var}}")
			ENDIF(${flag_var} MATCHES "/MDd")
		ENDFOREACH(flag_var)
	ENDIF (NOT USE_MSVC_RUNTIME_LIBRARY_DLL)

So in the VS project file I swapped from /MTd to /MDd but the problem remain.

3

Are you building 64 bit?

4

Do you mean Bullet? Yes I’m building 64 bit.

This is how the CMake program look like:

Untitled.png
Untitled.png914×1478 47.1 KB

This is the CMakeList.txt



cmake_minimum_required(VERSION 2.4.3)
set(CMAKE_ALLOW_LOOSE_LOOP_CONSTRUCTS true)
cmake_policy(SET CMP0017 NEW)
#this line has to appear before 'PROJECT' in order to be able to disable incremental linking
SET(MSVC_INCREMENTAL_DEFAULT ON)

PROJECT(BULLET_PHYSICS)
FILE (STRINGS "VERSION" BULLET_VERSION)

IF(COMMAND cmake_policy)
   cmake_policy(SET CMP0003 NEW)
   if(POLICY CMP0042)
      # Enable MACOSX_RPATH by default.
      cmake_policy(SET CMP0042 NEW)
   endif(POLICY CMP0042)
ENDIF(COMMAND cmake_policy)


IF (NOT CMAKE_BUILD_TYPE)
# SET(CMAKE_BUILD_TYPE "Debug")
 SET(CMAKE_BUILD_TYPE "Release")
ENDIF (NOT CMAKE_BUILD_TYPE)

SET(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} -D_DEBUG")
#MESSAGE("CMAKE_CXX_FLAGS_DEBUG="+${CMAKE_CXX_FLAGS_DEBUG})

OPTION(USE_DOUBLE_PRECISION "Use double precision"	OFF)
OPTION(USE_GRAPHICAL_BENCHMARK "Use Graphical Benchmark" ON)
OPTION(BUILD_SHARED_LIBS "Use shared libraries" OFF)
OPTION(USE_SOFT_BODY_MULTI_BODY_DYNAMICS_WORLD "Use btSoftMultiBodyDynamicsWorld" OFF)

OPTION(BULLET2_USE_THREAD_LOCKS "Build Bullet 2 libraries with mutex locking around certain operations (required for multi-threading)" OFF)
IF (BULLET2_USE_THREAD_LOCKS)
    OPTION(BULLET2_USE_OPEN_MP_MULTITHREADING "Build Bullet 2 with support for multi-threading with OpenMP (requires a compiler with OpenMP support)" OFF)
    OPTION(BULLET2_USE_TBB_MULTITHREADING "Build Bullet 2 with support for multi-threading with Intel Threading Building Blocks (requires the TBB library to be already installed)" OFF)
    IF (MSVC)
        OPTION(BULLET2_USE_PPL_MULTITHREADING "Build Bullet 2 with support for multi-threading with Microsoft Parallel Patterns Library (requires MSVC compiler)" OFF)
    ENDIF (MSVC)
ENDIF (BULLET2_USE_THREAD_LOCKS)

OPTION(USE_MSVC_INCREMENTAL_LINKING "Use MSVC Incremental Linking" OFF)
OPTION(USE_CUSTOM_VECTOR_MATH "Use custom vectormath library" OFF)

#statically linking VC++ isn't supported for WindowsPhone/WindowsStore
IF (CMAKE_SYSTEM_NAME STREQUAL WindowsPhone OR CMAKE_SYSTEM_NAME STREQUAL WindowsStore)
	OPTION(USE_MSVC_RUNTIME_LIBRARY_DLL "Use MSVC Runtime Library DLL (/MD or /MDd)" ON)
ELSE ()
	OPTION(USE_MSVC_RUNTIME_LIBRARY_DLL "Use MSVC Runtime Library DLL (/MD or /MDd)" OFF)
ENDIF (CMAKE_SYSTEM_NAME STREQUAL WindowsPhone OR CMAKE_SYSTEM_NAME STREQUAL WindowsStore)

#SET(CMAKE_EXE_LINKER_FLAGS_INIT    "/STACK:10000000 /INCREMENTAL:NO")
#SET(CMAKE_EXE_LINKER_FLAGS    "/STACK:10000000 /INCREMENTAL:NO")

#MESSAGE("MSVC_INCREMENTAL_YES_FLAG"+${MSVC_INCREMENTAL_YES_FLAG})

IF(MSVC)
	IF (NOT USE_MSVC_INCREMENTAL_LINKING)
		#MESSAGE("MSVC_INCREMENTAL_DEFAULT"+${MSVC_INCREMENTAL_DEFAULT})
		SET( MSVC_INCREMENTAL_YES_FLAG "/INCREMENTAL:NO")

		STRING(REPLACE "INCREMENTAL:YES" "INCREMENTAL:NO" replacementFlags ${CMAKE_EXE_LINKER_FLAGS_DEBUG})
		SET(CMAKE_EXE_LINKER_FLAGS_DEBUG "/INCREMENTAL:NO ${replacementFlags}" )
		MESSAGE("CMAKE_EXE_LINKER_FLAGS_DEBUG=${CMAKE_EXE_LINKER_FLAGS_DEBUG}")

		STRING(REPLACE "INCREMENTAL:YES" "INCREMENTAL:NO" replacementFlags2 ${CMAKE_EXE_LINKER_FLAGS})

		SET(CMAKE_EXE_LINKER_FLAGS ${replacementFlag2})
		STRING(REPLACE "INCREMENTAL:YES" "" replacementFlags3 "${CMAKE_EXTRA_LINK_FLAGS}")

		SET(CMAKE_EXTRA_LINK_FLAGS ${replacementFlag3})


		STRING(REPLACE "INCREMENTAL:YES" "INCREMENTAL:NO" replacementFlags3 "${CMAKE_EXE_LINKER_FLAGS_RELWITHDEBINFO}")
		SET(CMAKE_EXE_LINKER_FLAGS_RELWITHDEBINFO ${replacementFlags3})
		SET(CMAKE_EXE_LINKER_FLAGS_RELWITHDEBINFO "/INCREMENTAL:NO ${replacementFlags3}" )

	ENDIF (NOT USE_MSVC_INCREMENTAL_LINKING)

	IF (NOT USE_MSVC_RUNTIME_LIBRARY_DLL)
		#We statically link to reduce dependancies
		FOREACH(flag_var CMAKE_CXX_FLAGS CMAKE_CXX_FLAGS_DEBUG CMAKE_CXX_FLAGS_RELEASE CMAKE_CXX_FLAGS_MINSIZEREL CMAKE_CXX_FLAGS_RELWITHDEBINFO CMAKE_C_FLAGS CMAKE_C_FLAGS_DEBUG CMAKE_C_FLAGS_RELEASE CMAKE_C_FLAGS_MINSIZEREL CMAKE_C_FLAGS_RELWITHDEBINFO )
			IF(${flag_var} MATCHES "/MD")
				STRING(REGEX REPLACE "/MD" "/MT" ${flag_var} "${${flag_var}}")
			ENDIF(${flag_var} MATCHES "/MD")
			IF(${flag_var} MATCHES "/MDd")
				STRING(REGEX REPLACE "/MDd" "/MTd" ${flag_var} "${${flag_var}}")
			ENDIF(${flag_var} MATCHES "/MDd")
		ENDFOREACH(flag_var)
	ENDIF (NOT USE_MSVC_RUNTIME_LIBRARY_DLL)

	IF (CMAKE_CL_64)
	  ADD_DEFINITIONS(-D_WIN64)
	ELSE()
	  OPTION(USE_MSVC_SSE "Use MSVC /arch:sse option"	ON)
	  option(USE_MSVC_SSE2 "Compile your program with SSE2 instructions" ON)

	  IF (USE_MSVC_SSE)
		  SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /arch:SSE")
	  ENDIF()
	  IF (USE_MSVC_SSE2)
		  SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /arch:SSE2")
	  ENDIF()

	ENDIF()

	option(USE_MSVC_AVX "Compile your program with AVX instructions"  OFF)

	IF(USE_MSVC_AVX)
		add_definitions(/arch:AVX)
	ENDIF()

	OPTION(USE_MSVC_FAST_FLOATINGPOINT "Use MSVC /fp:fast option"	ON)
	IF (USE_MSVC_FAST_FLOATINGPOINT)
		  SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /fp:fast")
  ENDIF()

	OPTION(USE_MSVC_STRING_POOLING "Use MSVC /GF string pooling option"	ON)
	IF (USE_MSVC_STRING_POOLING)
		SET(CMAKE_C_FLAGS "/GF ${CMAKE_C_FLAGS}")
		SET(CMAKE_CXX_FLAGS "/GF ${CMAKE_CXX_FLAGS}")
	ENDIF()

	OPTION(USE_MSVC_FUNCTION_LEVEL_LINKING "Use MSVC /Gy function level linking option"	ON)
	IF(USE_MSVC_FUNCTION_LEVEL_LINKING)
		SET(CMAKE_C_FLAGS "/Gy ${CMAKE_C_FLAGS}")
		SET(CMAKE_CXX_FLAGS "/Gy ${CMAKE_CXX_FLAGS}")
		set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} /OPT:REF")
		set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} /OPT:REF")
	ENDIF(USE_MSVC_FUNCTION_LEVEL_LINKING)

	OPTION(USE_MSVC_EXEPTIONS "Use MSVC C++ exceptions option"	OFF)



	OPTION(USE_MSVC_COMDAT_FOLDING "Use MSVC /OPT:ICF COMDAT folding option"	ON)

	IF(USE_MSVC_COMDAT_FOLDING)
		set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} /OPT:ICF")
		set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} /OPT:ICF")
	ENDIF()

	OPTION(USE_MSVC_DISABLE_RTTI "Use MSVC /GR- disabled RTTI flags option"	ON)
	IF(USE_MSVC_DISABLE_RTTI)
	  STRING(REGEX REPLACE "/GR" "" CMAKE_CXX_FLAGS ${CMAKE_CXX_FLAGS}) # Disable RTTI
		SET(CMAKE_C_FLAGS "/GR- ${CMAKE_C_FLAGS}")
		SET(CMAKE_CXX_FLAGS "/GR- ${CMAKE_CXX_FLAGS}")
	ENDIF(USE_MSVC_DISABLE_RTTI)

	SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /wd4244 /wd4267")
ENDIF(MSVC)



IF (WIN32)
OPTION(INTERNAL_CREATE_DISTRIBUTABLE_MSVC_PROJECTFILES "Create MSVC projectfiles that can be distributed" OFF)

IF (INTERNAL_CREATE_DISTRIBUTABLE_MSVC_PROJECTFILES)
	SET (LIBRARY_OUTPUT_PATH ${BULLET_PHYSICS_SOURCE_DIR}/lib CACHE PATH "Single output directory for building all libraries.")
	SET( CMAKE_RUNTIME_OUTPUT_DIRECTORY ${BULLET_PHYSICS_SOURCE_DIR})
	SET( CMAKE_RUNTIME_OUTPUT_DIRECTORY_DEBUG ${BULLET_PHYSICS_SOURCE_DIR})
	SET( CMAKE_RUNTIME_OUTPUT_DIRECTORY_RELEASE ${BULLET_PHYSICS_SOURCE_DIR})
	SET( CMAKE_RUNTIME_OUTPUT_DIRECTORY_MINSIZEREL ${BULLET_PHYSICS_SOURCE_DIR})
	SET( CMAKE_RUNTIME_OUTPUT_DIRECTORY_RELWITHDEBINFO ${BULLET_PHYSICS_SOURCE_DIR})
ELSE()
	SET (LIBRARY_OUTPUT_PATH ${CMAKE_BINARY_DIR}/lib CACHE PATH "Single output directory for building all libraries.")
ENDIF()



OPTION(INTERNAL_CREATE_MSVC_RELATIVE_PATH_PROJECTFILES "Create MSVC projectfiles with relative paths" OFF)
OPTION(INTERNAL_ADD_POSTFIX_EXECUTABLE_NAMES "Add MSVC postfix for executable names (_Debug)" OFF)

SET(CMAKE_DEBUG_POSTFIX "_Debug" CACHE STRING "Adds a postfix for debug-built libraries.")
SET(CMAKE_MINSIZEREL_POSTFIX "_MinsizeRel" CACHE STRING "Adds a postfix for MinsizeRelease-built libraries.")
SET(CMAKE_RELWITHDEBINFO_POSTFIX "_RelWithDebugInfo" CACHE STRING "Adds a postfix for ReleaseWithDebug-built libraries.")





IF (INTERNAL_CREATE_MSVC_RELATIVE_PATH_PROJECTFILES)
SET(CMAKE_SUPPRESS_REGENERATION  1)
SET(CMAKE_USE_RELATIVE_PATHS 1)
ENDIF(INTERNAL_CREATE_MSVC_RELATIVE_PATH_PROJECTFILES)

ENDIF (WIN32)


OPTION(BUILD_CPU_DEMOS "Build original Bullet CPU examples" ON)



OPTION(INTERNAL_UPDATE_SERIALIZATION_STRUCTURES "Internal update serialization structures" OFF)
IF (INTERNAL_UPDATE_SERIALIZATION_STRUCTURES)
ADD_DEFINITIONS( -DBT_INTERNAL_UPDATE_SERIALIZATION_STRUCTURES)
ENDIF (INTERNAL_UPDATE_SERIALIZATION_STRUCTURES)

IF (USE_DOUBLE_PRECISION)
ADD_DEFINITIONS( -DBT_USE_DOUBLE_PRECISION)
SET( BULLET_DOUBLE_DEF "-DBT_USE_DOUBLE_PRECISION")
ENDIF (USE_DOUBLE_PRECISION)

IF (USE_SOFT_BODY_MULTI_BODY_DYNAMICS_WORLD)
ADD_DEFINITIONS(-DUSE_SOFT_BODY_MULTI_BODY_DYNAMICS_WORLD)
ENDIF (USE_SOFT_BODY_MULTI_BODY_DYNAMICS_WORLD)

IF(USE_GRAPHICAL_BENCHMARK)
ADD_DEFINITIONS( -DUSE_GRAPHICAL_BENCHMARK)
ENDIF (USE_GRAPHICAL_BENCHMARK)

IF(BULLET2_USE_THREAD_LOCKS)
	ADD_DEFINITIONS( -DBT_THREADSAFE=1 )
	IF (NOT MSVC)
		SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
	ENDIF (NOT MSVC)
ENDIF (BULLET2_USE_THREAD_LOCKS)

IF (BULLET2_USE_OPEN_MP_MULTITHREADING)
    ADD_DEFINITIONS("-DBT_USE_OPENMP=1")
    IF (MSVC)
        SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /openmp")
    ELSE (MSVC)
        # GCC, Clang
        SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fopenmp")
    ENDIF (MSVC)
ENDIF (BULLET2_USE_OPEN_MP_MULTITHREADING)

IF (BULLET2_USE_TBB_MULTITHREADING)
    SET (BULLET2_TBB_INCLUDE_DIR "not found" CACHE PATH "Directory for Intel TBB includes.")
    SET (BULLET2_TBB_LIB_DIR "not found" CACHE PATH "Directory for Intel TBB libraries.")
    find_library(TBB_LIBRARY tbb PATHS ${BULLET2_TBB_LIB_DIR})
    find_library(TBBMALLOC_LIBRARY tbbmalloc PATHS ${BULLET2_TBB_LIB_DIR})
    ADD_DEFINITIONS("-DBT_USE_TBB=1")
    INCLUDE_DIRECTORIES( ${BULLET2_TBB_INCLUDE_DIR} )
    LINK_LIBRARIES( ${TBB_LIBRARY} ${TBBMALLOC_LIBRARY} )
ENDIF (BULLET2_USE_TBB_MULTITHREADING)

IF (BULLET2_USE_PPL_MULTITHREADING)
    ADD_DEFINITIONS("-DBT_USE_PPL=1")
ENDIF (BULLET2_USE_PPL_MULTITHREADING)

IF (WIN32)
OPTION(USE_GLUT "Use Glut"	ON)
ADD_DEFINITIONS( -D_CRT_SECURE_NO_WARNINGS )
ADD_DEFINITIONS( -D_CRT_SECURE_NO_DEPRECATE )
ADD_DEFINITIONS( -D_SCL_SECURE_NO_WARNINGS )

IF (USE_GLUT AND MSVC)
	string (REPLACE "/D_WINDOWS" "" CMAKE_CXX_FLAGS ${CMAKE_CXX_FLAGS})
	remove_definitions(-D_WINDOWS )
ENDIF()



ELSE(WIN32)
OPTION(USE_GLUT "Use Glut"	ON)
ENDIF(WIN32)


IF(COMMAND cmake_policy)
   cmake_policy(SET CMP0003 NEW)
ENDIF(COMMAND cmake_policy)


# This is the shortcut to finding GLU, GLUT and OpenGL if they are properly installed on your system
# This should be the case.

FIND_PACKAGE(OpenGL)
IF (OPENGL_FOUND)
	MESSAGE("OPENGL FOUND")
	MESSAGE(${OPENGL_LIBRARIES})
ELSE (OPENGL_FOUND)
	MESSAGE("OPENGL NOT FOUND")
	SET(OPENGL_gl_LIBRARY opengl32)
	SET(OPENGL_glu_LIBRARY glu32)
ENDIF (OPENGL_FOUND)


#FIND_PACKAGE(GLU)


IF (APPLE)
  FIND_LIBRARY(COCOA_LIBRARY Cocoa)
ENDIF()

OPTION(BUILD_BULLET3 "Set when you want to build Bullet 3" ON)

# Optional Python configuration
# builds pybullet automatically if all the requirements are met
SET(PYTHON_VERSION_PYBULLET "2.7" CACHE STRING "Python version pybullet will use.")
SET(Python_ADDITIONAL_VERSIONS 2.7 2.7.3 3 3.0 3.1 3.2 3.3 3.4 3.5 3.6)
SET_PROPERTY(CACHE PYTHON_VERSION_PYBULLET PROPERTY STRINGS ${Python_ADDITIONAL_VERSIONS})
SET(CMAKE_MODULE_PATH ${CMAKE_CURRENT_SOURCE_DIR}/build3/cmake ${CMAKE_MODULE_PATH})
OPTION(EXACT_PYTHON_VERSION "Require Python and match PYTHON_VERSION_PYBULLET exactly, e.g. 2.7.3" OFF)
IF(EXACT_PYTHON_VERSION)
  set(EXACT_PYTHON_VERSION_FLAG EXACT REQUIRED)
ENDIF(EXACT_PYTHON_VERSION)
# first find the python interpreter
FIND_PACKAGE(PythonInterp ${PYTHON_VERSION_PYBULLET} ${EXACT_PYTHON_VERSION_FLAG})
# python library should exactly match that of the interpreter
FIND_PACKAGE(PythonLibs ${PYTHON_VERSION_STRING} EXACT)
SET(DEFAULT_BUILD_PYBULLET OFF)
IF(PYTHONLIBS_FOUND)
	SET(DEFAULT_BUILD_PYBULLET ON)
ENDIF(PYTHONLIBS_FOUND)
OPTION(BUILD_PYBULLET "Set when you want to build pybullet (Python bindings for Bullet)" ${DEFAULT_BUILD_PYBULLET})

OPTION(BUILD_ENET "Set when you want to build apps with enet UDP networking support" ON)
OPTION(BUILD_CLSOCKET "Set when you want to build apps with enet TCP networking support" ON)


IF(BUILD_PYBULLET)

	OPTION(BUILD_PYBULLET_NUMPY "Set when you want to build pybullet with NumPy support" ON)
	OPTION(BUILD_PYBULLET_ENET "Set when you want to build pybullet with enet UDP networking support" ON)
	OPTION(BUILD_PYBULLET_CLSOCKET "Set when you want to build pybullet with enet TCP networking support" ON)

	OPTION(BUILD_PYBULLET_MAC_USE_PYTHON_FRAMEWORK "Set when you want to use the Python Framework on Mac" OFF)

	IF(BUILD_PYBULLET_NUMPY)
		#include(FindNumPy)
		FIND_PACKAGE(NumPy)
		if (PYTHON_NUMPY_FOUND)
			message("NumPy found")
			add_definitions(-DPYBULLET_USE_NUMPY)
		else()
			message("NumPy not found")
		endif()
	ENDIF()

	IF(WIN32)
		SET(BUILD_SHARED_LIBS OFF CACHE BOOL "Shared Libs" FORCE)
	ELSE(WIN32)
		SET(BUILD_SHARED_LIBS ON CACHE BOOL "Shared Libs" FORCE)
	ENDIF(WIN32)

	IF(APPLE)
		OPTION(BUILD_PYBULLET_MAC_USE_PYTHON_FRAMEWORK "Set when you want to use the Python Framework on Mac" ON)
		IF(NOT BUILD_PYBULLET_MAC_USE_PYTHON_FRAMEWORK)
			add_definitions(-DB3_NO_PYTHON_FRAMEWORK)
		ENDIF(NOT BUILD_PYBULLET_MAC_USE_PYTHON_FRAMEWORK)
		OPTION(BUILD_PYBULLET_SHOW_PY_VERSION "Set when you want to show the PY_MAJOR_VERSION and PY_MAJOR_VERSION using #pragme message." OFF)
		IF(BUILD_PYBULLET_SHOW_PY_VERSION)
			add_definitions(-DB3_DUMP_PYTHON_VERSION)
		ENDIF()

	ENDIF(APPLE)

ENDIF(BUILD_PYBULLET)

IF(BUILD_BULLET3)
	 IF(APPLE)
		MESSAGE("Mac OSX Version is ${_CURRENT_OSX_VERSION}")
		IF(_CURRENT_OSX_VERSION  VERSION_LESS 10.9)
			MESSAGE("Mac OSX below 10.9 has no OpenGL 3 support so please disable the BUILD_OPENGL3_DEMOS option")
			#unset(BUILD_OPENGL3_DEMOS CACHE)

			OPTION(BUILD_OPENGL3_DEMOS "Set when you want to build the OpenGL3+ demos" OFF)
		ELSE()
			OPTION(BUILD_OPENGL3_DEMOS "Set when you want to build the OpenGL3+ demos" ON)
		ENDIF()
	ELSE()
		OPTION(BUILD_OPENGL3_DEMOS "Set when you want to build Bullet 3 OpenGL3+ demos" ON)
	ENDIF()
ELSE(BUILD_BULLET3)
	unset(BUILD_OPENGL3_DEMOS CACHE)
	OPTION(BUILD_OPENGL3_DEMOS "Set when you want to build Bullet 3 OpenGL3+ demos" OFF)
ENDIF(BUILD_BULLET3)
IF(BUILD_OPENGL3_DEMOS)
	IF(EXISTS ${BULLET_PHYSICS_SOURCE_DIR}/Demos3 AND IS_DIRECTORY ${BULLET_PHYSICS_SOURCE_DIR}/Demos3)
		SUBDIRS(Demos3)
	ENDIF()
ELSE()
	ADD_DEFINITIONS(-DNO_OPENGL3)
ENDIF(BUILD_OPENGL3_DEMOS)

OPTION(BUILD_BULLET2_DEMOS "Set when you want to build the Bullet 2 demos" ON)
IF(BUILD_BULLET2_DEMOS)

	IF(EXISTS ${BULLET_PHYSICS_SOURCE_DIR}/examples AND IS_DIRECTORY ${BULLET_PHYSICS_SOURCE_DIR}/examples)
		SUBDIRS(examples)
	ENDIF()

ENDIF(BUILD_BULLET2_DEMOS)



OPTION(BUILD_EXTRAS "Set when you want to build the extras" ON)
IF(BUILD_EXTRAS)
  SUBDIRS(Extras)
ENDIF(BUILD_EXTRAS)


#Maya Dynamica plugin is moved to http://dynamica.googlecode.com

SUBDIRS(src)

IF("${CMAKE_GENERATOR}" MATCHES "Unix Makefiles")
	OPTION(INSTALL_LIBS "Set when you want to install libraries" ON)
ELSE()
	IF(APPLE AND FRAMEWORK)
		OPTION(INSTALL_LIBS "Set when you want to install libraries" ON)
	ELSE()
#by default, don't enable the 'INSTALL' option for Xcode and MSVC projectfiles
		OPTION(INSTALL_LIBS "Set when you want to install libraries" OFF)
	ENDIF()
ENDIF()

IF(INSTALL_LIBS)
	SET (LIB_SUFFIX "" CACHE STRING "Define suffix of directory name (32/64)" )
	SET (LIB_DESTINATION "lib${LIB_SUFFIX}" CACHE STRING "Library directory name")
	## the following are directories where stuff will be installed to
	SET(INCLUDE_INSTALL_DIR "include/bullet/" CACHE PATH "The subdirectory to the header prefix")
	SET(PKGCONFIG_INSTALL_PREFIX "lib${LIB_SUFFIX}/pkgconfig/" CACHE STRING "Base directory for pkgconfig files")
	IF(NOT MSVC)
	  CONFIGURE_FILE(${CMAKE_CURRENT_SOURCE_DIR}/bullet.pc.cmake ${CMAKE_CURRENT_BINARY_DIR}/bullet.pc @ONLY)
  	INSTALL(
		FILES
		${CMAKE_CURRENT_BINARY_DIR}/bullet.pc
		DESTINATION
		${PKGCONFIG_INSTALL_PREFIX})
	ENDIF(NOT MSVC)
ENDIF(INSTALL_LIBS)

#INSTALL of other files requires CMake 2.6
IF (${CMAKE_MAJOR_VERSION}.${CMAKE_MINOR_VERSION} GREATER 2.5)
	OPTION(INSTALL_EXTRA_LIBS "Set when you want extra libraries installed" OFF)
ENDIF (${CMAKE_MAJOR_VERSION}.${CMAKE_MINOR_VERSION} GREATER 2.5)

OPTION(BUILD_UNIT_TESTS "Build Unit Tests"	ON)

IF (BUILD_UNIT_TESTS)
	ENABLE_TESTING()
	SUBDIRS(test)
ENDIF()

set (BULLET_CONFIG_CMAKE_PATH lib${LIB_SUFFIX}/cmake/bullet )
list (APPEND BULLET_LIBRARIES LinearMath)
IF(BUILD_BULLET3)
    list (APPEND BULLET_LIBRARIES BulletInverseDynamics)
ENDIF(BUILD_BULLET3)
list (APPEND BULLET_LIBRARIES BulletCollision)
list (APPEND BULLET_LIBRARIES BulletDynamics)
list (APPEND BULLET_LIBRARIES BulletSoftBody)
set (BULLET_USE_FILE ${BULLET_CONFIG_CMAKE_PATH}/UseBullet.cmake)
configure_file 	( ${CMAKE_CURRENT_SOURCE_DIR}/BulletConfig.cmake.in
					${CMAKE_CURRENT_BINARY_DIR}/BulletConfig.cmake
					@ONLY ESCAPE_QUOTES
				)
install ( FILES ${CMAKE_CURRENT_SOURCE_DIR}/UseBullet.cmake
		${CMAKE_CURRENT_BINARY_DIR}/BulletConfig.cmake
		DESTINATION ${BULLET_CONFIG_CMAKE_PATH}
	)