Second Life Forums Archive - Particle/Effects question

Zaplok Riggles

Registered User

Join date: 25 Feb 2008

Posts: 119

03-01-2008 18:24

I created a particle effect to shoot a beam at a target. The problem is, instead of a beam, it looks like a stream of spheres pulsing towards the target (they are not tight enough to look like a solid stream). Also, what I want to do is create a particle "splat" or explosion at a the target spot. As far as I can see, particles can only originate from the object that is creating them. How can I cause a particle affect to originate from another point? Thanks!

Ollj Oh

Registered User

Join date: 28 Aug 2007

Posts: 522

03-01-2008 20:28

Particles are "viewer side effects" therfore:
- Particle density is client/viewer side.
--The client only sees particles if he can see the prim that emmits them.
--There is a limit of roughly 1000 to 4000 particles in a scene.

-It also means that particle effects are properties of the prim, and every prim can only have one particle system.
--particles can spawn in a sphere or ring around a prim (or at an offset region with some math). They can move away from there to a target KEY or wind and by an initial impulse. Thats pretty much it.
--usually you end up with 2 or more prims to achieve the desired particle effect.

http://wiki.secondlife.com/wiki/LlParticleSystem tells you to set up:

PSYS_SRC_BURST_RATE float Specifies the time interval, in seconds, between "bursts" of particles being emitted. Specifying a value of 0.0 will cause the emission of particles as fast as the viewer can do so.
PSYS_SRC_BURST_PART_COUNT integer Specifies the number of particles emitted in each "burst".

Zaplok Riggles

Registered User

Join date: 25 Feb 2008

Posts: 119

03-01-2008 20:36

From: Ollj Oh

Particles are "viewer side effects" therfore:
- Particle density is client/viewer side.
--The client only sees particles if he can see the prim that emmits them.
--There is a limit of roughly 1000 to 4000 particles in a scene.

-It also means that particle effects are properties of the prim, and every prim can only have one particle system.
--particles can spawn in a sphere or ring around a prim (or at an offset region with some math). They can move away from there to a target KEY or wind and by an initial impulse. Thats pretty much it.
--usually you end up with 2 or more prims to achieve the desired particle effect.

http://wiki.secondlife.com/wiki/LlParticleSystem tells you to set up:

PSYS_SRC_BURST_RATE float Specifies the time interval, in seconds, between "bursts" of particles being emitted. Specifying a value of 0.0 will cause the emission of particles as fast as the viewer can do so.
PSYS_SRC_BURST_PART_COUNT integer Specifies the number of particles emitted in each "burst".

I have this set as fast as possible and it still looks like bubbles shooting out quickly, not a continuous stream. I have seen some particle effects that were single beams and was wondering how those are achieved.

Hewee Zetkin

Registered User

Join date: 20 Jul 2006

Posts: 2,702

03-01-2008 20:41

Use a large scale in the y direction, and turn on the PSYS_PART_FOLLOW_VELOCITY_MASK flag. You'll want to set the other parameters such that the velocity isn't TOO great. That way the particles overlap rather than forming like a dashed line. You might also want to emit them at a distance of about half the y scale, so they don't originate from behind the emitter (from the side anyway; it's always going to look strange end-on).

Kahiro Watanabe

Registered User

Join date: 28 Sep 2007

Posts: 572

03-02-2008 04:45

Go to the particle laboratory sandbox you have a beam particle example. Or IM me.

Debbie Trilling

Our Lady of Peenemünde

Join date: 17 Oct 2006

Posts: 434

03-02-2008 05:51

'Beam' or 'lazer' effects are most usually easily created by having a narrow x-axis size co-ordinate and a long y-axis co-ordinate

Then minimum (start) size is 0.05; the maximum is 4.00.

When you do this, the texture you use becomes largely unimportant.

Now, having done that set pretty high speeds and use a _ANGLE pattern. Restrict both the begin and end angles as much as possible.

These are the keys to a good quality 'beam'

CODE


llParticleSystem([
        PSYS_PART_FLAGS, PSYS_PART_EMISSIVE_MASK,
        PSYS_SRC_PATTERN, PSYS_SRC_PATTERN_ANGLE,
        PSYS_PART_START_ALPHA, 1.00,
        PSYS_PART_END_ALPHA, 1.00,
        PSYS_PART_START_COLOR, <1.00,0.00,0.00>,
        PSYS_PART_END_COLOR, <1.00,0.00,0.00>,
        PSYS_PART_START_SCALE, <0.05,4.00,0.00>,
        PSYS_PART_END_SCALE, <0.05,4.00,0.00>,
        PSYS_PART_MAX_AGE, 3.50,
        PSYS_SRC_ANGLE_BEGIN, 0.00,
        PSYS_SRC_ANGLE_END, 0.00,
        PSYS_SRC_BURST_PART_COUNT, 20,
        PSYS_SRC_BURST_RATE, 0.10,
        PSYS_SRC_BURST_SPEED_MIN, 1.00,
        PSYS_SRC_BURST_SPEED_MAX, 7.50
    ]);

The viewer is capable of rendering 8192 particles at any one time. See 'Edit | Preferences | Adv. Graphics | Max. Particle Count:'

Particle/Effects question
Zaplok Riggles Registered User Join date: 25 Feb 2008 Posts: 119	03-01-2008 18:24 I created a particle effect to shoot a beam at a target. The problem is, instead of a beam, it looks like a stream of spheres pulsing towards the target (they are not tight enough to look like a solid stream). Also, what I want to do is create a particle "splat" or explosion at a the target spot. As far as I can see, particles can only originate from the object that is creating them. How can I cause a particle affect to originate from another point? Thanks!
Ollj Oh Registered User Join date: 28 Aug 2007 Posts: 522	03-01-2008 20:28 Particles are "viewer side effects" therfore: - Particle density is client/viewer side. --The client only sees particles if he can see the prim that emmits them. --There is a limit of roughly 1000 to 4000 particles in a scene. -It also means that particle effects are properties of the prim, and every prim can only have one particle system. --particles can spawn in a sphere or ring around a prim (or at an offset region with some math). They can move away from there to a target KEY or wind and by an initial impulse. Thats pretty much it. --usually you end up with 2 or more prims to achieve the desired particle effect. http://wiki.secondlife.com/wiki/LlParticleSystem tells you to set up: PSYS_SRC_BURST_RATE float Specifies the time interval, in seconds, between "bursts" of particles being emitted. Specifying a value of 0.0 will cause the emission of particles as fast as the viewer can do so. PSYS_SRC_BURST_PART_COUNT integer Specifies the number of particles emitted in each "burst".
Zaplok Riggles Registered User Join date: 25 Feb 2008 Posts: 119	03-01-2008 20:36 From: Ollj Oh Particles are "viewer side effects" therfore: - Particle density is client/viewer side. --The client only sees particles if he can see the prim that emmits them. --There is a limit of roughly 1000 to 4000 particles in a scene. -It also means that particle effects are properties of the prim, and every prim can only have one particle system. --particles can spawn in a sphere or ring around a prim (or at an offset region with some math). They can move away from there to a target KEY or wind and by an initial impulse. Thats pretty much it. --usually you end up with 2 or more prims to achieve the desired particle effect. http://wiki.secondlife.com/wiki/LlParticleSystem tells you to set up: PSYS_SRC_BURST_RATE float Specifies the time interval, in seconds, between "bursts" of particles being emitted. Specifying a value of 0.0 will cause the emission of particles as fast as the viewer can do so. PSYS_SRC_BURST_PART_COUNT integer Specifies the number of particles emitted in each "burst". I have this set as fast as possible and it still looks like bubbles shooting out quickly, not a continuous stream. I have seen some particle effects that were single beams and was wondering how those are achieved.
Hewee Zetkin Registered User Join date: 20 Jul 2006 Posts: 2,702	03-01-2008 20:41 Use a large scale in the y direction, and turn on the PSYS_PART_FOLLOW_VELOCITY_MASK flag. You'll want to set the other parameters such that the velocity isn't TOO great. That way the particles overlap rather than forming like a dashed line. You might also want to emit them at a distance of about half the y scale, so they don't originate from behind the emitter (from the side anyway; it's always going to look strange end-on).
Kahiro Watanabe Registered User Join date: 28 Sep 2007 Posts: 572	03-02-2008 04:45 Go to the particle laboratory sandbox you have a beam particle example. Or IM me.
Debbie Trilling Our Lady of Peenemünde Join date: 17 Oct 2006 Posts: 434	03-02-2008 05:51 'Beam' or 'lazer' effects are most usually easily created by having a narrow x-axis size co-ordinate and a long y-axis co-ordinate Then minimum (start) size is 0.05; the maximum is 4.00. When you do this, the texture you use becomes largely unimportant. Now, having done that set pretty high speeds and use a _ANGLE pattern. Restrict both the begin and end angles as much as possible. These are the keys to a good quality 'beam' CODE llParticleSystem([ PSYS_PART_FLAGS, PSYS_PART_EMISSIVE_MASK, PSYS_SRC_PATTERN, PSYS_SRC_PATTERN_ANGLE, PSYS_PART_START_ALPHA, 1.00, PSYS_PART_END_ALPHA, 1.00, PSYS_PART_START_COLOR, <1.00,0.00,0.00>, PSYS_PART_END_COLOR, <1.00,0.00,0.00>, PSYS_PART_START_SCALE, <0.05,4.00,0.00>, PSYS_PART_END_SCALE, <0.05,4.00,0.00>, PSYS_PART_MAX_AGE, 3.50, PSYS_SRC_ANGLE_BEGIN, 0.00, PSYS_SRC_ANGLE_END, 0.00, PSYS_SRC_BURST_PART_COUNT, 20, PSYS_SRC_BURST_RATE, 0.10, PSYS_SRC_BURST_SPEED_MIN, 1.00, PSYS_SRC_BURST_SPEED_MAX, 7.50 ]); The viewer is capable of rendering 8192 particles at any one time. See 'Edit \| Preferences \| Adv. Graphics \| Max. Particle Count:'

Welcome to the Second Life Forums Archive

Particle/Effects question