Difference between revisions of "Primitive"

Latest revision as of 09:38, 4 September 2023

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This article is about primitives. For LSL related information, see Category:LSL Prim.

A primitive, or prim, is a single-part object. Multi-part objects will have multiple parts ("prims").

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

Each prim is represented by a set of parameters, including shape/type, position, scale/size, rotation, cut, hollow, twist, shear, etc. These parameters are sent from a server to the viewer running on the resident's desktop, where the local video card is used to render the visual appearance of everything. (Rendering on the server would probably create a much higher amount of network traffic.)

The color, texture, bumpiness, shininess, and transparency of prims can also be adjusted, and images (textures) can be applied to each surface (face/side) of a prim to change its appearance. Box, cylinder, and prism prim shape types can also be made flexible.

Prims can be linked together into link sets. They can also be attached to avatars, but this process is separate from (thought similar to) linking.

In the Viewer source code, primitives are implemented in LLPrimitive, with vertex generation performed in LLVolume and rendering in LLVOVolume.

Shape types

There are eight primitive shape types (Building Block Type in the viewer's build tools).

Box

All kinds of rectangular shapes.

Cylinder

Round tables, floors, long pipes.

Prism

A box with one very small face if created with the object editing tool, otherwise a true, 5-sided solid if changed from another prim type.

Sphere

Can be used for ellipsoids of all shapes.

Torus

Most complex among normal prims, can be modified in many exotic ways.

Tube

Another form of hollow cylinder.

Ring

Another variant of torus.

Sculpted

Sculpted: new as of 2007, used for highly variable organic shapes.

Properties

Mass

The mass of a prim is a function of its volume, different prim shapes have different volumes thus different masses.

Mass Lab demonstrates how different shapes have different masses.

Survival

The survival of properties depends upon the type of the property and what happens to the object.

**Property survival**
Property	Script Set Not Running	Script Removal	Take unscripted and re-rez	Shift-drag-copy
Sit Target	Yes	Yes	Yes	?
Particles	Yes	Yes	Yes	?
Floating Text	Yes	Yes	Yes	No
Spin	Yes	No	?	?
Collision Sound	Yes	Yes	?	?
Looped Sound	Yes	Yes	Yes	No
Remote Script Access Pin	Yes	Yes	?	?
Light	Yes	Yes	Yes	Yes
Status	Yes	Yes	Yes	Yes
Buoyancy	?	No	No	?
Texture Animation	Yes	Yes	Yes	No

It should be noted that when a script (in an object) moves from one simulator into another while being set as "Not Running" (either by llSetScriptState or via the checkbox in the script editor) the script's state will be lost. See SVC-1853 for details.

Materials

There are seven primitive material types that determine things like friction and default collision sound:

stone
metal
glass
wood
flesh
plastic
rubber

Physics

Each prim shape has an automatic physics shape, which is shown in the Primitive_Physics illustration. The physics shape is the shape that the object makes for an avatar or pathfinding object interacting with it. By the use of twisting and cutting, a simple prim may become quite a complex shape.

To remove the physics shape of an object use Physics Optimization; use of phantom makes an object shapeless to avatars but does not remove its physics shape.

Help

Basic Prim Creation and Editing

Scripting

Category:LSL_Prim

Video tutorials

External links

Wikipedia: Geometric primitive

@@ Line 27: / Line 27: @@
 Prims can be linked together into [[link set]]s. They can also be attached to avatars, but this process is separate from (thought similar to) linking.
-In the Viewer [[source code]], primitives are implemented in LLPrimitive, with vertex generation performed in LLVolume and rendering in LLVOVolume.
+In the Viewer [[source code]], primitives are implemented in {{code|LLPrimitive}}, with vertex generation performed in {{code|LLVolume}} and rendering in {{code|LLVOVolume}}.
 ==Shape types==
-There are eight primitive shape types:
+There are eight primitive shape types ('''Building Block Type''' in the viewer's build tools).
-# box: all kinds of rectangular shapes
-# cylinder: round tables, floors, long pipes
+===Box===
-# prism: a box with one very small face
-# sphere: can be used for ellipsoids of all shapes
+[[File:Prim-Box.jpg|50px|left]]
-# torus: most complex, can be modified in many exotic ways
-# tube:  another form of hollow cylinder
+All kinds of rectangular shapes.
-# ring: another variant of torus
-# [[sculpt]]ed: new as of 2007, used for highly variable organic shapes
+===Cylinder===
+[[File:Prim-Cylinder.jpg|50px|left]]
+Round tables, floors, long pipes.
+===Prism===
+[[File:Prim-Prism.jpg|50px|left]]
+A box with one very small face if created with the object editing tool, otherwise a true, 5-sided solid if changed from another prim type.
+=== Sphere ===
+[[File:Prim-Sphere.jpg|50px|left]]
+Can be used for ellipsoids of all shapes.
+=== Torus ===
+[[File:Prim-Torus.jpg|50px|left]]
+Most complex among normal prims, can be modified in many exotic ways.
+===Tube===
+[[File:Prim-Tube.jpg|50px|left]]
+Another form of hollow cylinder.
+=== Ring ===
+[[File:Prim-Ring.jpg|50px|left]]
+Another variant of torus.
+=== Sculpted ===
+[[File:Prim-Sculpted.jpg|50px|left]]
+[[Sculpt]]ed: new as of 2007, used for highly variable organic shapes.
 ==Properties==
+==== Mass ====
+The [[mass]] of a prim is a function of its volume, different prim shapes have different volumes thus different masses.
+* [[Mass Lab]] demonstrates how different shapes have different masses.
+==== Survival ====
+The survival of properties depends upon the type of the property and what happens to the object.
 {| {{Prettytable}}
@@ Line 46: / Line 95: @@
 |- {{Hl2}}
 ! Property
+! Script Set Not Running
 ! Script Removal
 ! Take unscripted and re-rez
 ! Shift-drag-copy
 |-
-|| [[llSitTarget|Sit Target]] || Yes || Yes || ?
+|| [[llSitTarget|Sit Target]] || Yes || Yes || Yes || ?
 |-
-|| [[llParticleSystem|Particles]] || Yes || Yes || ?
+|| [[llParticleSystem|Particles]] || Yes || Yes || Yes || ?
 |-
-|| [[llTargetOmega|Spin]] || Yes || ? || ?
+|| [[llSetText|Floating Text]] || Yes || Yes || Yes || No
 |-
-|| [[llCollisionSound|Collision Sound]] || Yes || ? || ?
+|| [[llTargetOmega|Spin]] || Yes || No || ? || ?
 |-
-|| [[llSetRemoteScriptAccessPin|Remote Script Access Pin]] || Yes || ? || ?
+|| [[llCollisionSound|Collision Sound]] || Yes || Yes || ? || ?
 |-
-|| [[PRIM_POINT_LIGHT|Light]] || Yes || Yes || Yes
+|| [[llLoopSound|Looped Sound]] || Yes || Yes || Yes || No
 |-
-|| [[Temporary]] || Yes || Yes || Yes
+|| [[llSetRemoteScriptAccessPin|Remote Script Access Pin]] || Yes || Yes || ? || ?
+|-
+|| [[PRIM_POINT_LIGHT|Light]] || Yes || Yes || Yes || Yes
+|-
+|| {{LSLGC|Status}} || Yes || Yes || Yes || Yes
+|-
+|| [[llSetBuoyancy|Buoyancy]]
+|| ? || No || No || ?
+|-
+|| [[llSetTextureAnim|Texture Animation]]
+|| Yes || Yes || Yes || No
 |}
+It should be noted that when a script (in an object) moves from one simulator into another while being set as "Not Running" (either by [[llSetScriptState]] or via the checkbox in the script editor) the script's state will be lost. See {{Jira|SVC-1853}} for details.
+* {{Jira|SVC-3925}}
+* {{Jira|VWR-640}}
+* {{Jira|SVC-1242}}
 ==Materials==
-There are seven primitive [[material]] types that determine things like mass and sound:
+There are seven primitive [[material]] types that determine things like friction and default [[llCollisionSound|collision sound]]:
 # stone
 # metal
@@ Line 74: / Line 140: @@
 # plastic
 # rubber
+==Physics==
+Each prim shape has an automatic physics shape, which is shown in the [[Primitive_Physics]] illustration.  The physics shape is the shape that the object makes for an avatar or pathfinding object interacting with it.  By the use of twisting and cutting, a simple prim may become quite a complex shape.
+To remove the physics shape of an object use [[Physics Optimization]]; use of phantom makes an object shapeless to avatars but does not remove its physics shape.
 ==Help==
@@ Line 96: / Line 168: @@
 ==External links==
-* [http://en.wikipedia.org/wiki/Geometric_primitive Wikipedia: Geometric primitive]
+* {{Wikipedia|Geometric primitive|Wikipedia: Geometric primitive}}
+[[Category:Assets]]