Mesh/FAQ

Note: This page is still undergoing editorial revision!

Why is a mesh cube prim equivalence cost x and a prim cube is 1?

Prim count was not a realistic weight of the objects' resource usage and how they affect performance. However, we are not changing their contribution to resource costs on legacy objects in order to maintain existing content.

Why does my mesh prim equivalence cost depend on the object's scale?

Larger objects do use more streaming and physics cost resources -- they are visible from a greater distance (which means they need to be streamed to more viewers in an area) and they have a larger collision cross-section in the physics engine.

Why do meshes cost x in prim equivalence when they have the same number of triangles as a sculpted prim?

Prim count (in which a sculpted prim counts as 1) was not a realistic weight of the objects' resource usage and how they affect performance.

Why does my PE go up when I add a script?

The prim equivalent weight of an object increases when you add a script if the prim equivalence is determined by server weight. This happens only when the server weight is higher than either the streaming or physics weights of the object. Making an object dynamic (physical or scripted) increases the amount of work the server has to do to track that object. Most often, objects have a higher streaming or physics weight than server weight, so this only affects certain server-intensive pieces of content.

Tip: For highly detailed technical information about server cost, see Mesh Server Weight.

Why does my prim equivalence go way up when I link a mesh object to a prim (eg. torus)?

We want to more accurately display the true resource usage of content on the systems of Second Life and your computer. A torus prim is "only" one prim, but it actually creates a much larger load on the physics engine than other, less complex prim types such as a box or sphere.

I linked my mesh to a torus and its prim equivalence went way up. How do I bring the PE down to a reasonable value?

Set the Physics Shape type of the torus (found on the Features tab of the Build Tools window) to Convex Hull. The hollowness of the torus creates a high computational load on the physics engine. Setting it to Convex Hull simplifies the physics of the torus by putting a cap on the top and bottom, meaning you will no longer be able to stand inside the torus. If you don't need to collide with the torus at all, set the Physics Shape type of the torus to None. Note that the root prim of an object can never be set to Physics Shape type of None.

Why does my (prim object) PE go up when I make some prims have no physics shape?

When any prim in an object is set to a physics type other than "prim", the entire object's land impact is calculated using prim equivalence instead of the traditional prim count. This means that some prims in the linked set may be assigned a cost higher than one.

Why doesn't my mesh import properly?

Please create a thread on our mesh forum ( http://community.secondlife.com/t5/Mesh/bd-p/Mesh ) , and tag it with [UPLOAD]. We're working on creating an upload troubleshooting page, and this will help us to find common trouble areas and answer questions in the future.

I cannot upload a mesh. What are the prerequisites of uploading a mesh?

using a mesh viewer have billing info on your account took the IP test standing on land that you can build on (this req will be removed in the future) the viewer has capabilities (see bug https://jira.secondlife.com/browse/SH-1030 ) not experiencing a rare billing bug (http://community.secondlife.com/t5/Mesh/Mesh-enablement-trouble/td-p/1010933)

How can I reduce the PE of my uploaded mesh?

[Need a link to the release 2 viewer] (With the Mesh release 2 viewer) edit your object and click More Info. Figure out which of download weight, physics weight, and server weight is largest and causing the high PE. For objects with a large physics weight, a simple 2 step process will lower the PE. Set the Physics Shape type of the root prim and any object that needs a physics shape to Convex Hull, then set the Physics Shape type of the rest of the prims to None. For objects with a large streaming weight, try reducing the scale of the object, or provide better optimized levels of detail that reduce the number of triangles drawn when the object is viewed from a distance. For objects with a large server weight, try making the mesh out of fewer pieces, linking small objects together, removing scripts from the object.

How can I reduce the upload fee of my mesh?

A: Identify which of download weight, physics weight, and server weight is largest and attempt to minimize it. Click the "Calculate weights & fee" button to see these weights.

How do I reduce the download weight of my mesh model before I upload it?

A: Use fewer triangles for the 4 LODs of the model.

How do I reduce the physics weight of my mesh model before I upload it?

A: The Physics weight can be minimized by setting Physics > Use Level of Detail to Lowest. A: You can also minimize the physics after upload by linking the mesh to a box, then setting the physics shape type of the linked set to None. (Do you really need to link to another prim to do this?)sorry, that should have said physics weight. Only child prims can actually be set to none. When you set an object to physics shape type None, the root prim is left as is (right?) and all the child prims are set to None.

How do I reduce the server weight of my mesh model before I upload it?

A: Prefer single "large" mesh models over multiple separate meshes. A: Seperate and unlink passive (unscripted, non-physical) content such as walls or landscaping from active and dynamic content. A: https://wiki.secondlife.com/wiki/Mesh/Mesh_Server_Weight

How can I ensure my model looks good from a distance?

A: Test your model on the Aditi test grid. Scale the mesh to the target size. Watch the model while walking away until it disappears. Watch the model as you walk towards it. If the results are not satisfactory, play with the number of triangles in the 4 LODs in the upload dialog. Alternately, create custom LODs in a 3rd party program and upload them into the 4 LOD slots.

How do I test my model on ADITI (test grid) and upload it with the same settings on AGNI (main grid)?

Second Life saves your model upload parameters; when you upload a model on the Aditi test grid, you can upload it again on the main Second Life grid without needing to re-set all the parameters for the model.

Caution: Make sure to check your parameters before uploading! We cannot refund Linden dollars lost in erroneous uploads.

I'm uploading a rigged mesh (animated mesh to be worn on the avatar) and...

Please create a thread on our mesh forum ( http://community.secondlife.com/t5/Mesh/bd-p/Mesh ) , and tag it with [UPLOAD]. We're working on creating a upload troubleshooting page, and this will help us answer questions in the future.

Stop right there. Go see https://wiki.secondlife.com/wiki/Mesh/Troubleshooting (Again, this link does not actually go to a troubleshooting doc. However, we do have http://wiki.secondlife.com/wiki/Mesh/Uploading_and_wearing_a_rigged_mesh ) The Troubleshooting page is useful because the model must have certain bones to upload correctly. Should we incorporate that information somewhere else?