Tuesday, December 2, 2008

ALL YOU WANTED TO KNOW (ALMOST) ABOUT PRIMITIVES (PRIMS)

By Debbie Bulloch


What are Prims

Primitives or prims are Second Life’s (SL) building blocks. A prim is a single part object. Multi-part objects will have multiple prim parts. Think of a prim as a cell in an organism. Organisms can range from single-cell to multi-cells. Similarly, objects in SL may range from one-prim to multi-prims. You may also think of a prim as a kind of LEGO building block.

In SL, virtual physical objects such as cars, houses, jewelry, and even less obvious things like hair are made out of one or more prims. Objects made from prims are usually created in-world using SL’s built in object editing tool. This tool is used for all sorts of 3D modeling in SL, playing the same role as 3D Max, Maya, or Blender, but customized for the Second Life way of doing things.

Prims can be modified in various ways, such as size, twists, shearing, and cutting. Also, images (textures) such as photographs can be applied to each surface of a prim to change its appearance. Perfect examples of this are the beautiful rugs sold by many SL vendors. Take a prim, flatten it out into the shape of a rug, apply a texture (for example, a photograph of a rug design) already in your computer and voila you have just made a rug.

Types of prims

There are eight different types of prims:

1. box: all kinds of rectangular shapes;
2. cylinder: round tables, floors, long pipes;
3. prism: a box with one very small face;
4. sphere: can be used for ellipsoids of all shapes;
5. torus: most complex, can be modified in many exotic ways;
6. tube: another form of hollow cylinder;
7. ring: another variant of tours; and
8. sculpted: new as of 2007, used for highly variable organic shapes.

Prims are important to builders because builders must learn to link, or arrange, prims to create various objects. Again, think of prims as LEGO blocks. Anyone who has watched a child play with LEGO blocks to build objects, knows that different size and shape LEGO blocks must be linked together in order to create an object. The more skilled the child is in arranging LEGO blocks together, the more complex her creations will be. The same is true for SL builders; the more skilled and experienced builders can create amazingly fantastic objects using the very same prims that are available to everyone in SL.



Why should non-builders care about prims?

Understanding prims, and how they work, is also important to non-builders and here is why. SL is a graphic, virtual world that runs on computer power. It takes a lot of processing power to make SL run as well as it does. (I know that some of you like to complain about how laggy SL can be at times, or how it often crashes for no apparent reason, but talk to the people who left text-only chat to join SL and they will tell you how vastly superior SL is to anything else out there, so stop the bellyaching already!). So Linden Labs have limited the amount of prims that can be rezzed (or put) in-world.

Each parcel of land can only support a finite number of prims. Houses, furniture, landscaping, boats, vehicles, animals, toys, etc., EVERYTHING that you rezz or put in a parcel of land adds up towards the parcel’s prim limit. There is a formula to determine how many prims a particular parcel of land can support. The formula goes like this:

(Square meters/65536) X 15000 = Prim limit

So if you own a parcel of land that is 512 sq. meters (the basic SL parcel), your parcel would support the following number of prims:

(512/65536) X 15000 = Prim limit
0.0078125 X 15000 = 117.1875 (or 117) prims


There are some parcels that can support extra (bonus) prims beyond the 117 prims per 512 sq. meters standard. Similarly, there are other parcels where the number of prims allowed is less than the standard 117 prims per 512 sq. meters count (Open Space is an example).

Figuring out how many prims a parcel supports

To see how many prims a parcel actually supports open the About Land dialog box. You can open the About Land dialog box by right-clicking on the ground of the land that you want to check.

This is what the About Land dialog window looks like:



When the About Land dialog box opens, click on the Objects tab. You will then see the Objects window. The Objects window looks like this:



In the example above you will see the following information regarding primitives:

Primitives parcel supports: 2702
Primitives on parcel: 796

In this particular example, the parcel can support a total of 2702 prims with 796 prims being curently used. This means that the parcel may support an additional 1906prims. But if the parcel owner tries to rezz objects that add to more than 1906 prims, SL will not allow him to rezz the objects and he will get an error message stating that he is “over prims.”

Figuring out how many prims are in an object

You can always see how many prims are in any object. This is true even if you do not own the object or do not have rights to the object. Right-click on the object, when the object's pie dialog appears, click on Edit.

This is what the pie dialog looks like:



You will then see the Edit dialog box. (If you get the abbreviated Edit dialog box, click on More and you will get the full Edit dialog box.) On the General tab area look down, about halfway down the dialog box, and you will see how many prims are in the object you are looking at.

The illustration below shows that there is one object, and the object uses only one prim.



A quick word about freebies and prims

There many generous individuals in SL. They freely give away their creations so they may be shared with anyone. Some freebies, however, come with a prim penalty. It is not that freebies are bad; it is just that many times freebies, especially freebie furniture, are the result of a builder’s first creations, when she was still new to building.

The more advance builders are particularly skillful at creating wonderful object using the least amount of prims. It takes a truly talented individual to be able to create very intricate objects using very few prims. In fact, there are builders who take pride in being to build the most beautiful houses using the least amount of prims; for them it becomes a sort of a friendly competition to see how much they can build with the fewest number of prims.

Do a search in SL using the term “low prims” and you will find a large number of shops that specialize in selling low-prim objects. Some of these objects are amazingly deatailed even though they use very few prims. Check them out!

Finally – Why are prims important at Between Homes?

Between Homes was created, and continues to exists, through the generosity of its supporters. Three current members have bought (and continue to buy) land to donate to BH. (You can see who these individuals are by looking up the group’s information dialog box). Other members have made donations of tiers that then allow BH to buy more land. Finally, there are other members who have donated their building and other skills to make BH what it is – a friendly place for homeless avis to visit and stay a while.

All of this, of course, comes with a price tag. Land is expensive and monthly tiers can add up after a while. Building supplies and scripts can also cost money. In order to be able to provide a nice environment to as many avis as possible we need to limit the number of prims that are used by each resident. The main grounds at BH, as well as all the “annexes,” are very nicely decorated and beautifully landscaped. In addition to the apartments, BH has a dance floor, a pond with fishes and diving board (frozen for the winter and ready for ice skating), a park, a chapel and various other areas. All of the above requires the use of lots and lots of prims.

Help us help you - keep your prim usage to 60 or less. And if you hear from me, from Yucca or from any of the BH officers that you are over prims we are not being mean, we just want everyone to have a great time.

For additional information on prims, land and other fun stuff, please watch this short SL video tutorial.

1 comment:

Anonymous said...

hi hi !
your explanations are very interesting and I think it is a good idea to explain what it consists on because in fact when you are new in sl or not , it is not so easy to understand what does that mean ! so thank you for this explanation and the video is quite clear too ! you should be a writer or a teacher ! maybe a journalist for Los Angeles Times or New York Times ! ha ha ! your are our BH reporter ! that's nice ! thank you ! and I can tell everyone that yucca and Deb only want to help you for your happiness ! they are very sweet ! thank you yucca and deb ! kisses
arc