OpenMW/cmake/CheckBulletPrecision.cmake

set(TMP_ROOT ${CMAKE_BINARY_DIR}/try-compile)
file(MAKE_DIRECTORY ${TMP_ROOT})

file(WRITE ${TMP_ROOT}/checkbullet.cpp
"
#include <BulletCollision/CollisionShapes/btSphereShape.h>
int main(int argc, char** argv)
{
    btSphereShape shape(1.0);
    btScalar mass(1.0);
    btVector3 inertia;
    shape.calculateLocalInertia(mass, inertia);
    return 0;
}
")

message(STATUS "Checking if Bullet uses double precision")

try_compile(RESULT_VAR
    ${TMP_ROOT}/temp
    ${TMP_ROOT}/checkbullet.cpp
    COMPILE_DEFINITIONS "-DBT_USE_DOUBLE_PRECISION"
    LINK_LIBRARIES ${BULLET_LIBRARIES}
    CMAKE_FLAGS  "-DINCLUDE_DIRECTORIES=${BULLET_INCLUDE_DIRS}"
    )
set(HAS_DOUBLE_PRECISION_BULLET ${RESULT_VAR})