Improving CMake rebuild times

[dermont]

It appears that when disabling/enabling a plugin/component from cmake-gui the build OgreBuildSettings.h is regenerated, requiring a complete rebuild of everything.

I understand the need for the plugin defines for a static build and the component defines for the Samples but is there not a way overcome this?

I understand this is probably not an issue for most since build times are probably low but here on an out-dated machine it takes Linux(Unity)-25 mins / MinGW -40 mins and Visual Studio - 1.5 hours.

It may be frustrating for new users to find that when encountering problems building plugins on say MinGW/DirectX* to find disabling a plugin from the cmake-gui restarts the whole build.

[masterfalcon]

It's possible. Even though those component and plugin defines are mostly used for samples, that file is still the best place for them to be. Think about 3rd party libraries or tools that may or may not rely on them being there or needing to know some information about how Ogre was configured at build time.

Now, I'm only theorizing about that. I don't know if that's actually the case. It would be good to get feedback from others.