Hi Elena, I agree the documentation isn't great, and it doesn't really emphasise a change that we made early in IC616 which removed the need to set a global grid (the danger with a global grid is that if somebody changes it, it could affect your pcell - unless of course you always set the grid at the beginning of your pcell code). I'll make some suggestions to tech pubs to improve it. It really could do with some good examples too. However, the main benefit is that rodCoord objects are essentially integers (64 bit integers underneath) and so don't suffer from rounding errors like floating point numbers do. You can do arithmetic on these rodCoord objects, and snap to grid easily without all the dangers that can occur with floating point numbers. I've not really used them much myself (mainly for historical reasons), but I do think they can take away some of the pain of dealing with floating point numbers in calculations for doing layout work. Essentially the database itself uses integers underneath, so you're working in a similar fashion when using rodCoord. They were added at the request of one of our major customers - but take them or leave them - you don't have to use them! Regards, Andrew.
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