Second Life Forums Archive - llSensor and agent vs avatar

Illuminous Beltran

Registered User

Join date: 4 Dec 2006

Posts: 5

03-03-2007 13:21

According to what I understand, a users' digital representation consists of 2 elements, an agent, and an avatar. The agent being your camera and percept, and the avatar the visual element.

I am trying to secure an area using llSensor. It works fine when the agent is attached to the avatar, but when I move the avatar out of range, and 'detach' the agent from the avatar, using the ALT-ZOOM, the sensor does not pick up the agent. Using this technique, I can use the agent to pass through walls, enter areas without sensor detection, and interact with objects in the 'restricted' sensor area.

The constant in llSensor parameter, AGENT, therefore seems to actually apply to the AVATAR, and not the AGENT. Am I missing something or confused by terminology? Thanks for any insight.

Illuminous Beltran

Registered User

Join date: 4 Dec 2006

Posts: 5

03-03-2007 13:28

I guess one solution might be to put the secure area inside of a structure whose dimensions exceed the maximum distance an agent can detach from and avatar, like a large cube with a smaller cube in the middle, out of range. Then permitted avatars can move the avatar into the area, while unauthorized agents can penetrate the external layer, but never reach the secured area. This seems like a prim-expensive approach though.

AJ DaSilva

woz ere

Join date: 15 Jun 2005

Posts: 1,993

03-03-2007 13:58

To put it really basically, the avatar is the graphics that display an agent's position in the world. The location of a camera is a property of the agent and only accessible by scripts which the user gives permission to.

Pale Spectre

Registered User

Join date: 2 Sep 2005

Posts: 586

03-03-2007 14:07

http://www.lslwiki.net/lslwiki/wakka.php?wakka=AgentandAvatar

From: LSL Wiki : AgentandAvatar

A user's presence in Second Life is represented by two entities: an agent and an avatar.

An agent is a client's presence within a simulator. All users connect to a sim as an agent. An agent is not an avatar, though it is represented on the client by one. An agent can be an object creator/owner and/or a group member. An agent "sees" the world through a camera and has an avatar.

An avatar is a visual representation of an agent within Second Life; it is the body other users see and interact with. Avatars can wear clothing, have bodyparts, and constantly play animations (if they didn't, they would just stand with their legs spread wide and their arms stretched out to the sides in a neutral position). Avatars can have attachments and are affected by physics.

The terms "agent" and "avatar" are often used interchangably. While this is technically incorrect, even Linden Lab has neglected the differences between these two entities when naming LSL's built-in functions, so it's more practical to make a page combining the two.

...in any event, I think what you're referring to is the camera, which is another thing again. llGetCameraPos can be used to detect its position but this requires the agent/avatar (aka the user behind the keyboard

) to grant permission.

Learjeff Innis

musician & coder

Join date: 27 Nov 2006

Posts: 817

03-04-2007 09:00

There is little hope of real privacy in SL. Not a problem for me, but that's how it is.

Nexus Laguna

Registered User

Join date: 20 Dec 2006

Posts: 40

03-04-2007 16:49

The problem you are having is with understanding the concept of avatar and agent. An agent is like a grand daddy of OBJECTS. Even an avatar is an object in SL. Agent refers to any object including prims and avatars etc.

Because avatars are so unique in SL they have their own properties too. They have all the properties of an agent (size, coordiantes, etc) but also unique ones just for an avatar.

If you understand the concept of Object Oriented Programming, an agent is essentially the parent object to the avatar object. The agent object is also the parent to the primitive object as primitives have unique characeristics.

Hope that makes sense and helps you out

ed44 Gupte

Explorer (Retired)

Join date: 7 Oct 2005

Posts: 638

03-04-2007 18:28

My understanding is that the camera is controlled by the client and the agent/av by the server, so the only way to get privacy is by the server not sending out info on the area you want private. There have been many threads about this, mainly in the features area.

One day, with an improved client, we might be able to have different views of ourselves walking so we don't have to look at our butts all the time, ok for fems, not so good for us fellows!

AJ DaSilva

woz ere

Join date: 15 Jun 2005

Posts: 1,993

03-04-2007 18:30

From: ed44 Gupte

One day, with an improved client, we might be able to have different views of ourselves walking so we don't have to look at our butts all the time, ok for fems, not so good for us fellows!

We can do that ourselves now we've got scriptable camera control. I guess nobody does because it sucks trying to walk without seeing where you're going.

Winter Ventura

Eclectic Randomness

Join date: 18 Jul 2006

Posts: 2,579

03-04-2007 19:39

Here's a representation of my best guess what the agent is.

BTW it's a prim, and when you sit on something, it becomes part of the linkset. It's physical, and is not phantom. An animation can move your avatar, without moving your agent.. And the nametag appears to be attached to the agent, similar to floating text on a prim.

_____________________

● Inworld Store: http://slurl.eclectic-randomness.com
● Website: http://www.eclectic-randomness.com
● Twitter: @WinterVentura

AJ DaSilva

woz ere

Join date: 15 Jun 2005

Posts: 1,993

03-04-2007 19:44

From: Winter Ventura

Here's a representation.

Of what?

AJ DaSilva

woz ere

Join date: 15 Jun 2005

Posts: 1,993

03-04-2007 19:52

From: Winter Ventura

Here's a representation of my best guess what the agent is.

As far as the world (i.e. physics) is concerned, like I guess your example is showing, it's a stretched sphere.

Winter Ventura

Eclectic Randomness

Join date: 18 Jul 2006

Posts: 2,579

03-04-2007 20:12

that makes a bit more sense.. I haven't any way to tell the shape.. I just know that the agent can get hung up on stuff in a vehicle. (unable to driver under low bridges, etc)

_____________________

● Inworld Store: http://slurl.eclectic-randomness.com
● Website: http://www.eclectic-randomness.com
● Twitter: @WinterVentura

Jeff Kelley

Registered User

Join date: 8 Nov 2006

Posts: 223

03-05-2007 10:09

From: Illuminous Beltran

I guess one solution might be to put the secure area inside of a structure whose dimensions exceed the maximum distance an agent can detach from and avatar

You need a 256x256x256 structure. Wow! Better buying a private island.

AJ DaSilva

woz ere

Join date: 15 Jun 2005

Posts: 1,993

03-05-2007 10:11

From: Jeff Kelley

You need a 256x256x256 structure. Wow! Better buying a private island.

Nah, bigger than that. You'd need a border of 256m on each side.

Deanna Trollop

BZ Enterprises

Join date: 30 Jan 2006

Posts: 671

03-06-2007 11:34

From: Illuminous Beltran

I guess one solution might be to put the secure area inside of a structure whose dimensions exceed the maximum distance an agent can detach from and avatar

Which still doesn't work, because the 50m avatar-camera distance constraint (camera, not agent) can be disabled in the debug settings. The only way to ensure privacy is to own an island.

From: AJ DaSilva

You'd need a border of 256m on each side.

562, if you want to keep anything inside the "secure area" from being transmitted to a client who's agent is outside the buffer zone. Apparently, the sim only sends data on objects and avatars which are within draw distance (max. 512) + 50m of that client's agent, regardless of where that agent's camera is (since the camera is assumed to stay within a 50m radius of the agent). Land data, however, is sent when within draw distance of camera, even when the camera is multiple sims away from its agent.

AJ DaSilva

woz ere

Join date: 15 Jun 2005

Posts: 1,993

03-06-2007 11:43

Duh... 512 draw distance != 512 visible area. Silly me.

Didn't know about the extra 50m, but I will question the land data being sent depending on camera position. 'Nuff times I've had missing land that would only appear if I pointed the agent at it.

Deanna Trollop

BZ Enterprises

Join date: 30 Jan 2006

Posts: 671

03-06-2007 11:51

From: AJ DaSilva

but I will question the land data being sent depending on camera position. 'Nuff times I've had missing land that would only appear if I pointed the agent at it.

Eh? Pointed the camera at it, you mean? Can you elaborate on what you mean by "missing land?"

AJ DaSilva

woz ere

Join date: 15 Jun 2005

Posts: 1,993

03-06-2007 11:58

No, I mean point the agent at. As in turn the avatar around to face that direction.

The land data hasn't been sent, so it's either not displayed or reverts to a hight of 0 (never checked which, possibly there's no difference). It looks like a sheer cliff dropping right down below the water level. Mostly it happens over sim borders, but I've had it in the same sim too.

Deanna Trollop

BZ Enterprises

Join date: 30 Jan 2006

Posts: 671

03-06-2007 12:49

Ah... that could just be a delay in transmission due to server load, and turning the av might be coincidental. I've had my camera more than 3 sims away from my av, and it usually takes a while for land data to load at that distance.

And after double-checking in-world, I'll retract the +50m extension, for objects at least. From my skybox at 700m, with draw distance of 512, I'm receiving objects on the ground (ground height ~100m), not only below me, but 2 sims away, and land as far as 4 sims away.

Land seems to load according to parcel boundaries. Parcels completely within a certain distance (or maybe whose center falls within that distance) seem to load completely, with the falloff cutting across parcels that don't. But I'm definitely not getting any avs at that distance.

AJ DaSilva

woz ere

Join date: 15 Jun 2005

Posts: 1,993

03-06-2007 12:59

The av turning fixed it too often for it to be coincidence, and it's happened after sitting working on stuff facing the other direction for a while, so if it is server load then it's forgetting to send it again after failing. Not a big issue really, and I've bug reported it, but I'm sure it's not working the way it should.

As far as land/object/avatar viewing distances, it seems to me that land does indeed load furthest away, then objects, and avatars have to be closer than anything else to be visible.

I'll agree with the parcel thing, seen some funny shaped trenches in my time.

AJ DaSilva

woz ere

Join date: 15 Jun 2005

Posts: 1,993

03-06-2007 19:15

Somehow I managed to write half the posts in this thread without thinking. Land is totally loaded dependent on camera position, of course.

llSensor and agent vs avatar
Illuminous Beltran Registered User Join date: 4 Dec 2006 Posts: 5	03-03-2007 13:21 According to what I understand, a users' digital representation consists of 2 elements, an agent, and an avatar. The agent being your camera and percept, and the avatar the visual element. I am trying to secure an area using llSensor. It works fine when the agent is attached to the avatar, but when I move the avatar out of range, and 'detach' the agent from the avatar, using the ALT-ZOOM, the sensor does not pick up the agent. Using this technique, I can use the agent to pass through walls, enter areas without sensor detection, and interact with objects in the 'restricted' sensor area. The constant in llSensor parameter, AGENT, therefore seems to actually apply to the AVATAR, and not the AGENT. Am I missing something or confused by terminology? Thanks for any insight.
Illuminous Beltran Registered User Join date: 4 Dec 2006 Posts: 5	03-03-2007 13:28 I guess one solution might be to put the secure area inside of a structure whose dimensions exceed the maximum distance an agent can detach from and avatar, like a large cube with a smaller cube in the middle, out of range. Then permitted avatars can move the avatar into the area, while unauthorized agents can penetrate the external layer, but never reach the secured area. This seems like a prim-expensive approach though.
AJ DaSilva woz ere Join date: 15 Jun 2005 Posts: 1,993	03-03-2007 13:58 To put it really basically, the avatar is the graphics that display an agent's position in the world. The location of a camera is a property of the agent and only accessible by scripts which the user gives permission to.
Pale Spectre Registered User Join date: 2 Sep 2005 Posts: 586	03-03-2007 14:07 http://www.lslwiki.net/lslwiki/wakka.php?wakka=AgentandAvatar From: LSL Wiki : AgentandAvatar A user's presence in Second Life is represented by two entities: an agent and an avatar. An agent is a client's presence within a simulator. All users connect to a sim as an agent. An agent is not an avatar, though it is represented on the client by one. An agent can be an object creator/owner and/or a group member. An agent "sees" the world through a camera and has an avatar. An avatar is a visual representation of an agent within Second Life; it is the body other users see and interact with. Avatars can wear clothing, have bodyparts, and constantly play animations (if they didn't, they would just stand with their legs spread wide and their arms stretched out to the sides in a neutral position). Avatars can have attachments and are affected by physics. The terms "agent" and "avatar" are often used interchangably. While this is technically incorrect, even Linden Lab has neglected the differences between these two entities when naming LSL's built-in functions, so it's more practical to make a page combining the two. ...in any event, I think what you're referring to is the camera, which is another thing again. llGetCameraPos can be used to detect its position but this requires the agent/avatar (aka the user behind the keyboard ) to grant permission.
Learjeff Innis musician & coder Join date: 27 Nov 2006 Posts: 817	03-04-2007 09:00 There is little hope of real privacy in SL. Not a problem for me, but that's how it is.
Nexus Laguna Registered User Join date: 20 Dec 2006 Posts: 40	03-04-2007 16:49 The problem you are having is with understanding the concept of avatar and agent. An agent is like a grand daddy of OBJECTS. Even an avatar is an object in SL. Agent refers to any object including prims and avatars etc. Because avatars are so unique in SL they have their own properties too. They have all the properties of an agent (size, coordiantes, etc) but also unique ones just for an avatar. If you understand the concept of Object Oriented Programming, an agent is essentially the parent object to the avatar object. The agent object is also the parent to the primitive object as primitives have unique characeristics. Hope that makes sense and helps you out
ed44 Gupte Explorer (Retired) Join date: 7 Oct 2005 Posts: 638	03-04-2007 18:28 My understanding is that the camera is controlled by the client and the agent/av by the server, so the only way to get privacy is by the server not sending out info on the area you want private. There have been many threads about this, mainly in the features area. One day, with an improved client, we might be able to have different views of ourselves walking so we don't have to look at our butts all the time, ok for fems, not so good for us fellows!
AJ DaSilva woz ere Join date: 15 Jun 2005 Posts: 1,993	03-04-2007 18:30 From: ed44 Gupte One day, with an improved client, we might be able to have different views of ourselves walking so we don't have to look at our butts all the time, ok for fems, not so good for us fellows! We can do that ourselves now we've got scriptable camera control. I guess nobody does because it sucks trying to walk without seeing where you're going.
Winter Ventura Eclectic Randomness Join date: 18 Jul 2006 Posts: 2,579	03-04-2007 19:39 Here's a representation of my best guess what the agent is. BTW it's a prim, and when you sit on something, it becomes part of the linkset. It's physical, and is not phantom. An animation can move your avatar, without moving your agent.. And the nametag appears to be attached to the agent, similar to floating text on a prim. _____________________ ● Inworld Store: http://slurl.eclectic-randomness.com ● Website: http://www.eclectic-randomness.com ● Twitter: @WinterVentura
AJ DaSilva woz ere Join date: 15 Jun 2005 Posts: 1,993	03-04-2007 19:44 From: Winter Ventura Here's a representation. Of what?
AJ DaSilva woz ere Join date: 15 Jun 2005 Posts: 1,993	03-04-2007 19:52 From: Winter Ventura Here's a representation of my best guess what the agent is. As far as the world (i.e. physics) is concerned, like I guess your example is showing, it's a stretched sphere.
Winter Ventura Eclectic Randomness Join date: 18 Jul 2006 Posts: 2,579	03-04-2007 20:12 that makes a bit more sense.. I haven't any way to tell the shape.. I just know that the agent can get hung up on stuff in a vehicle. (unable to driver under low bridges, etc) _____________________ ● Inworld Store: http://slurl.eclectic-randomness.com ● Website: http://www.eclectic-randomness.com ● Twitter: @WinterVentura
Jeff Kelley Registered User Join date: 8 Nov 2006 Posts: 223	03-05-2007 10:09 From: Illuminous Beltran I guess one solution might be to put the secure area inside of a structure whose dimensions exceed the maximum distance an agent can detach from and avatar You need a 256x256x256 structure. Wow! Better buying a private island.
AJ DaSilva woz ere Join date: 15 Jun 2005 Posts: 1,993	03-05-2007 10:11 From: Jeff Kelley You need a 256x256x256 structure. Wow! Better buying a private island. Nah, bigger than that. You'd need a border of 256m on each side.
Deanna Trollop BZ Enterprises Join date: 30 Jan 2006 Posts: 671	03-06-2007 11:34 From: Illuminous Beltran I guess one solution might be to put the secure area inside of a structure whose dimensions exceed the maximum distance an agent can detach from and avatar Which still doesn't work, because the 50m avatar-camera distance constraint (camera, not agent) can be disabled in the debug settings. The only way to ensure privacy is to own an island. From: AJ DaSilva You'd need a border of 256m on each side. 562, if you want to keep anything inside the "secure area" from being transmitted to a client who's agent is outside the buffer zone. Apparently, the sim only sends data on objects and avatars which are within draw distance (max. 512) + 50m of that client's agent, regardless of where that agent's camera is (since the camera is assumed to stay within a 50m radius of the agent). Land data, however, is sent when within draw distance of camera, even when the camera is multiple sims away from its agent.
AJ DaSilva woz ere Join date: 15 Jun 2005 Posts: 1,993	03-06-2007 11:43 Duh... 512 draw distance != 512 visible area. Silly me. Didn't know about the extra 50m, but I will question the land data being sent depending on camera position. 'Nuff times I've had missing land that would only appear if I pointed the agent at it.
Deanna Trollop BZ Enterprises Join date: 30 Jan 2006 Posts: 671	03-06-2007 11:51 From: AJ DaSilva but I will question the land data being sent depending on camera position. 'Nuff times I've had missing land that would only appear if I pointed the agent at it. Eh? Pointed the camera at it, you mean? Can you elaborate on what you mean by "missing land?"
AJ DaSilva woz ere Join date: 15 Jun 2005 Posts: 1,993	03-06-2007 11:58 No, I mean point the agent at. As in turn the avatar around to face that direction. The land data hasn't been sent, so it's either not displayed or reverts to a hight of 0 (never checked which, possibly there's no difference). It looks like a sheer cliff dropping right down below the water level. Mostly it happens over sim borders, but I've had it in the same sim too.
Deanna Trollop BZ Enterprises Join date: 30 Jan 2006 Posts: 671	03-06-2007 12:49 Ah... that could just be a delay in transmission due to server load, and turning the av might be coincidental. I've had my camera more than 3 sims away from my av, and it usually takes a while for land data to load at that distance. And after double-checking in-world, I'll retract the +50m extension, for objects at least. From my skybox at 700m, with draw distance of 512, I'm receiving objects on the ground (ground height ~100m), not only below me, but 2 sims away, and land as far as 4 sims away. Land seems to load according to parcel boundaries. Parcels completely within a certain distance (or maybe whose center falls within that distance) seem to load completely, with the falloff cutting across parcels that don't. But I'm definitely not getting any avs at that distance.
AJ DaSilva woz ere Join date: 15 Jun 2005 Posts: 1,993	03-06-2007 12:59 The av turning fixed it too often for it to be coincidence, and it's happened after sitting working on stuff facing the other direction for a while, so if it is server load then it's forgetting to send it again after failing. Not a big issue really, and I've bug reported it, but I'm sure it's not working the way it should. As far as land/object/avatar viewing distances, it seems to me that land does indeed load furthest away, then objects, and avatars have to be closer than anything else to be visible. I'll agree with the parcel thing, seen some funny shaped trenches in my time.
AJ DaSilva woz ere Join date: 15 Jun 2005 Posts: 1,993	03-06-2007 19:15 Somehow I managed to write half the posts in this thread without thinking. Land is totally loaded dependent on camera position, of course.

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llSensor and agent vs avatar