Prims

Four table legs = four prims

Prims, which is short for Primatives, are the basic building block of SL objects. By default they start out as a 0.5 meter square cube when you use your SL viewer's Build function. But they can become just about any shape you can imagine. Think of a basic dining room table. It has a flat surface with four legs. You can create a prim (rez a prim) and stretch it to the table top's size then create four prims stretched to the proper dimensions to represent the table legs. Move them into position so that everything looks right and there you go, a dining room table! This is a very simplified example of object creation in SL but it's to help illustrate the meaning of prims in SL and how they affect your virtual 'life' there.

Plus top = five prims

In the above example, our dining room table requires 5 prims to create. One for each leg and one for the table's surface. It is very important to know the number of prims an object is made up of. Because SL exists on computer servers, each location (region/sim) or parcel has a limit to the number of prims it can process. The more prims a piece of virtual land can process, the higher the tier (rent) cost.

Full region sims can contain up to 15,000 prims. The sim owner can divide his land into smaller sections called parcels. Each parcel will have a limit on the number of prims it can contain usually based on the parcel size. For example, if the sim owner divides his land into quarters, each quarter could contain up to 3750 prims or one quarter of the full sim's 15,000 prim limit. Once that prim limit is reached, the parcel or land can contain no more prims. If you try to rez an item or build something, you will receive an error message telling you that the region is full and no other prims can be created. This is why it is very important that land owners perform what I refer to as Prim Management.

I could go right ahead and fill my Homestead Sim (3750 prims) right up but there would be all sorts of problems with that. First off, I have devices on my land which create prims as you use them. If there were no free prims available, then that device would not function. The first thing that comes to mind are the palm trees I have on the nude beach. Those are capable of rezzing pillows for cuddling, a master's chair for spanking and a rope swing for two among other items. Without the free prims this device requires, it is useless. Therefore, a free reserve of prims must be maintained at all times.

The magic number of free prims for me is between 500 and 600. This ensures that my friends can rez their items and use them. It also ensures that devices such as palm trees, beds, board games and the like will function properly. I also have a rezzing vendor which allows potential customers to walk through my buildings so that they have a good idea of what they might be purchasing. They simply browse through the pictures in the vendor and click on a Rez button once they see something they are interested in. The vendor rezzes the building and the customer can walk through it to check it out before purchase. Some of these buildings can be hundreds of prims, so it's a good idea to have hundreds of free prims available on the land.

If my friends want to rez their vehicles, such as cars, boats, cycles or aircraft, then there must be enough free prims for them to do so. On the other end of the spectrum I have had friends rez their toys and actually just leave them there for me to return to their inventories later. This is just plain rude. We should all be responsible for the 'messes' we create. Go ahead and rez your stuff, but clean up after yourself when you are done with it. It's just common courtesy.

While a region or parcel has a limited number on the prims that it can contain, there is an exception. Any devices or objects attached to an avatar do not count against the prim limit. For example, I have some leather bracelets which are studded. They are 250 prims each and when I wear them, I wear both of them. When I attach them to my wrists, their prims do not count against my sim's prim limit. But they do create lag (which I'll deal with more in a future posting). Lag is undesirable and it is basically the effect perceived when  computer server is slowing down due to over processing. So while the number of prims on a necklace or skirt or head of hair do not count against the land's prim limits, it they do require extra processing. If I were to rez those bracelets onto the ground though, the prims that make them up would count against the land's prim limit.

In future posts, I'll go into more detail concerning other types of prims and also the causes of lag and what it does to dampen the SL experience.