Porting from Xilinx to Altera

Hi

I've just started pretty well the same process as well. I am interested in knowing is there a datasheet for all the Altera "design elements" (ie Xilinx has DCM's, BRAMS etc etc) I have looked at the MegaWizard which seems to contain these sorts of things, but no datasheets seem to be avail...

Also is there an equivalent to the unisim library? With Xilinx you would just do:

library unisim;

use unisim.vcomponents.all;

and would be able to instantiate any of the Xilinx design elements. I have found the altera_mf and seem to have successfully instantiated the alt_shift_taps into my design

library altera_mf;

use work.altera_mf_components.all;

but I'm not confident that this is how Altera intended. Do you have to go through the MegaWizard and create all the components by hand? And if so then what happens when the next version of Quartus comes out and subtle changes are made to the design elements?? Do you have to do them all again??

Thanks