I'm planning on using Ogre for an upcoming project. I'm hoping to add soft shadows to the engine. Does anyone have any experience making modifications to the engine and how easy/hard it is? I'm just trying to get a rough time estimate for planning.

Well taken from an Ogre wiki:

Quote:Ogre does not support soft shadows as part of the engine. If you want soft shadows you will need to write your own vertex and fragment programs.

So actually in this case, you are going to be writing those script file programs isntead of actually modifying the Ogre engine. Well you could do either or actually, I do not know anything about writing those script programs, so not sure how hard/easy those are. As for modifying the Ogre engine, it's straightforward, there's great documentation, but be warned that the engine itself is HUGE. You cannot actively change and recompile each time, because it would take too long. That's probabally why shaders are a lot better option because you can simply code and develop those, then use them in the engine. As for writing the soft shadows themselves, GameDev has an article here. To get started with the programs, take a look at the start of the documentation here.

So if you are able to get a fragment/vertext program done, then it's just a matter of using it correctly in the engine, which won't take but maybe a day or two depending if everything is working as expected effect wise + the time for writing/debugging that program.

If you have to modify the Ogre engine itself, then you are looking at maybe a week or two to implement in soft shadows. Most of that time is coming from having to recompile and test. Unless you are really good and can write it the first time without needing to compile during, the time will definitly be longer.

Of course those are just broad estimates, not sure really how long it'd take you and your team. Good luck!