[Rock-dev] Rock.cmake

[Peter Soetens]

Could someone explain me why there is this parallel effort in
rock.cmake, which mirrors partially the UseOrocos-RTT.cmake macros ?

The major feedback we got from the Orocos workshop was that there was
a need for a single build system, for both ros, rock and 'pure' orocos
users. What we're now looking at is that the Orocos toolchain can be
installed first, then ros and/or rock are installed and it will depend
on the application package if it's going to be a rosbuild ( no make
install ) or a standard build (with make install). ros would come with
a stack that integrates an existing orocos toolchain installation into
the ros eco system. rock would need to do the same, but orogen
generates packages that are buildable as a ros package, using the
UseOrocos-RTT.cmake macros. Furthermore, we could define a cmake macro
is_ros_package() that returns true if the current package is in a
ROS_PACKAGE_PATH instead of checking against the ROS_ROOT environment
variable (which might be accidentally set).

Looking at the rock.cmake file, it appears now orogen projects will
never work in a ros build environment.If you had used the
UseOrocos-RTT.cmake macros, the generated orogen code would have been
buildable by ROS users too.

I'm really looking for a solution here and not for an argument. If we
don't fix this soon, we'll loose (again) our momentum, and they will
not be moving to rock, but to ros. Guarantee you that.

Peter