PRIM TYPE PRISM

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Description

Constant: integer PRIM_TYPE_PRISM = 2;

The integer constant PRIM_TYPE_PRISM has the value 2

PRIM_TYPE_PRISM is a parameter of PRIM_TYPE used to make prim into a prism and to change specific properties that define the shape of that prism.

[ PRIM_TYPE, PRIM_TYPE_PRISM, integer hole_shape, vector cut, float hollow, vector twist, vector top_size, vector top_shear ]

[ PRIM_TYPE, PRIM_TYPE_PRISM, integer hole_shape, vector cut, float hollow, vector twist, vector top_size, vector top_shear ]
• integer hole_shape PRIM_HOLE_* flag
• vector cut x and y range from 0.0 to 1.0, x must be at least 0.05 smaller than y (z is ignored)
• float hollow ranges from 0.0 (solid) to 0.95 (maximum hollowed)
• vector twist ranges from -1.0 (-180 degree in the edit window) to 1.0 (+180 degree in the edit window) for both x and y (z is ignored)
• vector top_size ranges from 0.0 to 1.0 to 2.0 for both x and y (z is ignored)!
• vector top_shear ranges from -0.5 to 0.5 for both x and y (z is ignored)
hole_shape Flags Shape hole_shape Flags Shape
PRIM_HOLE_DEFAULT 0x00 Default PRIM_HOLE_SQUARE 0x20 Square
PRIM_HOLE_CIRCLE 0x10 Circle PRIM_HOLE_TRIANGLE 0x30 Triangle

[ 1, PRIM_TYPE_PRISM, vector cut, float hollow, float twist, vector top_size, vector top_shear ]

[ 1, PRIM_TYPE_PRISM, vector cut, float hollow, float twist, vector top_size, vector top_shear ]
• vector cut x and y range from 0.0 to 1.0, x must be at least 0.05 smaller than y (z is ignored)
• float hollow ranges from 0.0 (solid) to 0.95 (maximum hollowed)
• float twist ranges from -0.5 (-180 degree in the edit window) to 0.5 (+180 degree in the edit window)
• vector top_size ranges from 0.0 to 1.0 for both x and y (z is ignored)!
• vector top_shear ranges from -0.5 to 0.5 for both x and y (z is ignored)

This is the old PRIM_TYPE format for boxes (PRIM_TYPE used to be 1 instead of 9). Use the new format unless you are maintaining old code.

Caveats

  • The prim description is limited to 127 bytes; any string longer then that will be truncated. This truncation does not always happen when the attribute is set or read.
  • The pipe character '|' and the newline character '\n' are not legal in a prim's description. They will be replaced with '?'.[2]
  • Note that when people have "Hover Tips on All Objects" selected in the viewer's "View" menu, they'll see the object description pop-up for any object under their mouse pointer. For that reason, it is good practice to only set human-friendly information in the description, e.g. keys and such.
  • When an attached object is detached, changes made by script to the name and description (of the root prim) of the attachment will be lost. While the object is attached the name and description can be changed but it will not be reflected in inventory. This caveat does not apply to child prims.
  • If texture is missing from the prim's inventory and it is not a UUID or it is not a texture then an error is shouted on DEBUG_CHANNEL.
  • If texture is a UUID then there are no new asset permissions consequences for the object.
    • The resulting object develops no new usage restrictions that might have occurred if the asset had been placed in the prims inventory.
  • repeats is not only used to set the number of repeats but the sign of the individual components is also used to set the "Flip" attribute.
  • In the default texture mapping mode the texture repeats units are in texture repeats per face. In the planar texture mapping mode the texture repeats units are in texture repeats per half meter. This is in contrast to the in-world editing tool, in which the planar texture scaling units are repeats per meter.
  • If render_material is missing from the prim's inventory and it is not a UUID or it is not a material then an error is shouted on DEBUG_CHANNEL.
  • If render_material is a UUID then there are no new asset permissions consequences for the object.
    • The resulting object develops no new usage restrictions that might have occurred if the asset had been placed in the prims inventory.
  • If render_material is provided as NULL_KEY, the glTF Material is removed from face, reverting back to any underlying Blinn-Phong materials.
  • In the default texture mapping mode the texture repeats units are in texture repeats per face. In the planar texture mapping mode the texture repeats units are in texture repeats per half meter. This is in contrast to the in-world editing tool, in which the planar texture scaling units are repeats per meter.
  • Do not rely on Floating Text as a storage medium; it is neither secure nor finalized.
    • Floating text has been altered in past server updates, breaking existing content; future changes may occur.
    • Even "invisible"[3] floating text is transmitted to the client.
      • It can be viewed by anyone with a client that is capable of rendering text that is supposed to be invisible.
      • The network packets that contain the text can be sniffed and the text read.
  • top_size and client values are different, the ranges do not line up, conversion is required. This simple equation can be used: answer = 1.0 - value. See top_size Explained for more information.
  • PRIM_OMEGA on nonphysical objects, and child prims of physical objects, is only a client side effect; the object or prim will collide as non-moving geometry.
  • PRIM_OMEGA cannot be used on avatars sitting on the object. It will emit the error message "PRIM_OMEGA disallowed on agent".
  • If PRIM_OMEGA does not appear to be working, make sure that that Develop > Network > Velocity Interpolate Objects is enabled on the viewer.
  • In the parameters returned by llGetPrimitiveParams([PRIM_OMEGA]), the vector is normalized, and the spinrate is multiplied by the magnitude of the original vector.
  • If texture is missing from the prim's inventory and it is not a UUID or it is not a texture then an error is shouted on DEBUG_CHANNEL.
  • If texture is a UUID then there are no new asset permissions consequences for the object.
    • The resulting object develops no new usage restrictions that might have occurred if the asset had been placed in the prims inventory.
  • repeats is not only used to set the number of repeats but the sign of the individual components is also used to set the "Flip" attribute.
  • To clear the normal map parameters from the face (and possibly remove the material), set texture to NULL_KEY (the other parameters must be supplied in this case but will be ignored).
  • Note that whenever any face in a linkset contains a material (i.e. has a non-default PRIM_NORMAL, PRIM_SPECULAR, or PRIM_ALPHA_MODE), the linkset will use the new accounting system.
  • In the default texture mapping mode the texture repeats units are in texture repeats per face. In the planar texture mapping mode the texture repeats units are in texture repeats per half meter. This is in contrast to the in-world editing tool, in which the planar texture scaling units are repeats per meter.
  • If texture is missing from the prim's inventory and it is not a UUID or it is not a texture then an error is shouted on DEBUG_CHANNEL.
  • If texture is a UUID then there are no new asset permissions consequences for the object.
    • The resulting object develops no new usage restrictions that might have occurred if the asset had been placed in the prims inventory.
  • repeats is not only used to set the number of repeats but the sign of the individual components is also used to set the "Flip" attribute.
  • To clear the specular map parameters from the face (and possibly remove the material), set texture to NULL_KEY (the other parameters must be supplied in this case but will be ignored).
  • Note that whenever any face in a linkset contains a material (i.e. has a non-default PRIM_NORMAL, PRIM_SPECULAR, or PRIM_ALPHA_MODE), the linkset will use the new accounting system.
  • In the default texture mapping mode the texture repeats units are in texture repeats per face. In the planar texture mapping mode the texture repeats units are in texture repeats per half meter. This is in contrast to the in-world editing tool, in which the planar texture scaling units are repeats per meter.
  • If PRIM_LINK_TARGET's link_target describes a seated avatar...
  • If face is ALL_SIDES then the flag works on all sides.
  • The flag silently fails if its face value indicates a face that does not exist.

Important Issues

~ All Issues ~ Search JIRA for related Bugs
   We need PRIM_ALPHA_MODE_DEFAULT to revert alpha to old "if the texture has an alpha mask, use alpha. If not, don't" behavior.

Related Articles

Constants

•  PRIM_TYPE
•  CHANGED_SHAPE

Functions

•  llSetPrimitiveParams
•  llSetLinkPrimitiveParams
•  llGetPrimitiveParams
•  llGetLinkNumber Returns the link number of the prim the script is in.

Events

•  changed

Articles

•  Limits SL limits and constrictions
•  Limits SL limits and constrictions
•  Color in LSL
•  Translucent Color
•  Color in LSL
•  Color in LSL
•  Translucent Color

Examples

<lsl>llSetPrimitiveParams([PRIM_TYPE,

                       PRIM_TYPE_PRISM, 
                           PRIM_HOLE_DEFAULT,  // hole_shape
                           <0.00, 1.0, 0.0>,   // cut
                           0.0,                // hollow
                           <0.0, 0.0, 0.0>,    // twist
                           <1.0, 1.0, 0.0>,    // top_size
                           <0.0, 0.0, 0.0>     // top_Shear
                     ]);</lsl>

Notes

Link Numbers

Each prim that makes up an object has an address, a link number. To access a specific prim in the object, the prim's link number must be known. In addition to prims having link numbers, avatars seated upon the object do as well.

  • If an object consists of only one prim, and there are no avatars seated upon it, the (root) prim's link number is zero.
  • However, if the object is made up of multiple prims or there is an avatar seated upon the object, the root prim's link number is one.

When an avatar sits on an object, it is added to the end of the link set and will have the largest link number. In addition to this, while an avatar is seated upon an object, the object is unable to link or unlink prims without unseating all avatars first.

Counting Prims & Avatars

There are two functions of interest when trying to find the number of prims and avatars on an object.

integer GetPrimCount() { //always returns only the number of prims
    if(llGetAttached())//Is it attached?
        return llGetNumberOfPrims();//returns avatars and prims but attachments can't be sat on.
    return llGetObjectPrimCount(llGetKey());//returns only prims but won't work on attachments.
}
See llGetNumberOfPrims for more about counting prims and avatars.

Errata

If a script located in a child prim erroneously attempts to access link 0, it will get or set the property of the linkset's root prim. This bug (BUG-5049) is preserved for broken legacy scripts.

Deep Notes

PRIM_TYPE top_size and client taper conversion
Range[4] Top
Tapered
No
Tapering
Bottom
Tapered
Client [-1, 1] 1.0 0.0 -1.0
PRIM_TYPE [0, 2] 0.0 1.0 2.0
LEGACY [0, 1] 0.0 1.0 NA
Client < 1.11 [0, 1] 0.0 1.0 NA

top_size Explained

When the original PRIM_TYPE interface was retired (PRIM_TYPE_LEGACY, SL 1.5), the new PRIM_TYPE interface did not yet support tapering of the bottom of the prim, this feature wasn't added until SL 1.11 (two years later). Instead of retiring the new PRIM_TYPE when it was added, the range of top_size was enlarged; meanwhile in the client they redefined the parameter and it's values. This redefinition and range enlargement resulted in two interfaces that did the same thing but achieved it through different values. Meanwhile PRIM_TYPE_LEGACY's interface was not updated to support tapering of the bottom of the prim. Consequently all three interfaces have different ranges, making for a rather nasty caveat.

All Issues

~ Search JIRA for related Issues
   CHANGED_TEXTURE is not triggered when texture is changed via script
   CHANGED_TEXTURE is not triggered when texture is changed via script
   CHANGED_TEXTURE is not triggered when texture is changed via script
   CHANGED_TEXTURE is not triggered when texture is changed via script
   We need PRIM_ALPHA_MODE_DEFAULT to revert alpha to old "if the texture has an alpha mask, use alpha. If not, don't" behavior.

Footnotes

  1. ^ When LL deprecated this flag they stripped it of it's name, however they did not remove the functionality. To aid in documenting the functionality, the value was given a new name in the documentation only. That is why PRIM_TYPE_LEGACY is not recognized by the compiler.
  2. ^ The pipe character historically has been used to separate fields in the serialized version of inventory. The field is not multi-line so the newline character holds no meaning in this context.
  3. ^ Floating text with an alpha set to 0.0 is rendered "invisible"
  4. ^ The ranges in this article are written in Interval Notation.
  5. ^ LINK_ROOT does not work on single prim objects. Unless there is an avatar sitting on the object.

Signature

integer PRIM_TYPE_PRISM = 2;