Nope it shouldn't be too hard. I'm sorry it's taking so long for a new release of IrrLua. I just haven't had time. I've also been hesitant to start since Irrlicht 1.3 should be here any day now.
Usually, not much changes between versions. You may be able to simply copy the IrrLua sources into an Irrlicht 1.2 folder and rebuild. The few items that break can be commented out if you don't need them.
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Any idea about how hard it would be to update IrrLua to Irrlicht 1.2? Are there a lot of API changes?
Nope it shouldn't be too hard. I'm sorry it's taking so long for a new release of IrrLua. I just haven't had time. I've also been hesitant to start since Irrlicht 1.3 should be here any day now.
If you can build from source Ok, there was a patch posted to the forums: http://irrlicht.sourceforge.net/phpBB2/viewtopic.php?t=6309&start=75
Usually, not much changes between versions. You may be able to simply copy the IrrLua sources into an Irrlicht 1.2 folder and rebuild. The few items that break can be commented out if you don't need them.