I thought it could be useful to add a sticky information about mayaToCorona.
mayaToCorona is currently in closed beta. If you want to participate, have a look here:
https://groups.google.com/forum/?fromgroups#!topic/openmaya-mayatocorona/8uJULQujx0QThe plugin already supports most of the features wich are available for corona. But it is still missing a lot of other features. Unfortunatly for maya there is no way to use the maya shading network directly for plugin renderers, at least not yet. For mayaToCorona a workaround was develped with the usage of OpenShadingLaguage. This means that all maya nodes has to be translated to osl shading language what takes some time and some nodes will not match the maya nodes like fractal, noise marble etc. But they will be similiar.
Unfortunatly we have a basic problem here: OSL texture evaluation and Corona maps are not directly compatible. That means you can use maya shading nodes as input for a Corona surface shader or corona maps. But you
cannot use a corona map as input for a OSL node. e.g. you cannot use the maya blendColors node and connect tow corona materials to the inputs. Another problem is that the OSL version of the the file texture is a bit slow and I could not find out why this is the case. You can get the fastest rendering if you use Corona-only textures what limits you to file textures and other Corona specific maps/shaders.
At the moment the plugin is available for Maya2015 and Maya2016.
You can check the list of known bugs on the github site, there you can see if the bug is already resolved:
https://github.com/haggi/OpenMaya/milestones/mayaToCorona
