Effects

Effects are visual features rendered by the viewer from a few parameters set by a script. Once set, most of them keep running with no further script activity: the script describes the effect, it does not animate it frame by frame.

High quality effects often combine features: a technical mesh shape made in a modelling tool such as Blender, with an animated texture and glow, can look like particles while costing far less.

Concepts

Particle systems
- A prim can emit one particle system, described by a list of rules for the emitter pattern, particle lifetime, size, color, speed, texture and flags
- Combine flags with the bitwise OR operator (|)
- An empty list stops the system; another prim in the linkset can be set too
Hover text
- Floating text above a prim, with a color and alpha
- It is a prim property, so it stays when the script is removed
Texture animation
- Plays frames from a grid on a texture, or scrolls, rotates or scales the texture, entirely in the viewer
- Works on any prim in the linkset
Light, glow and full bright
- Prims can be point lights or projectors
- Faces can glow or ignore lighting
- PBR materials add emissive color
Media and sound
- Web pages on faces (textures) and sound round out many effects

Functions and events

`void`	`llParticleSystem(list rules)`
`void`	`llLinkParticleSystem(integer link, list rules)`
`void`	`llSetText(string text, vector color, float alpha)`
`void`	`llSetTextureAnim(integer mode, integer face, integer sizex, integer sizey, float start, float length, float rate)`
`void`	`llSetLinkTextureAnim(integer link, integer mode, integer face, integer sizex, integer sizey, float start, float length, float rate)`
`void`	`llSetLinkPrimitiveParamsFast(integer link, list rules)`

Particles

Particle rules are PSYS_* constants: emitter (PSYS_SRC_*) and particle (PSYS_PART_*) settings. See the reference below.

Technical mesh

A mesh shaped for the effect, with texture animation and glow, can replace many particles.

Scripting Details

`void`	`llParticleSystem(list rules)` Creates or updates a particle system on the prim containing the script based on rules. An empty list removes the particle system.
`void`	`llLinkParticleSystem(integer link, list rules)` Creates or updates a particle system on the linked prim link based on the list of rules. An empty list removes the particle system.
`void`	`llSetText(string text, vector color, float alpha)` Displays floating text above the prim with the specified color vector and transparency alpha.
`void`	`llSetTextureAnim(integer mode, integer face, integer sizex, integer sizey, float start, float length, float rate)` Animates the texture on face of the prim by setting its scale and offset. mode defines options, sizex/sizey define frames, start defines the start frame/angle, length defines duration, and rate defines playback speed.
`void`	`llSetLinkTextureAnim(integer link, integer mode, integer face, integer sizex, integer sizey, float start, float length, float rate)` Animates the texture on face of the linked prim link by setting the scale and offset according to mode. Parameters sizex/sizey define frames, start defines the start frame/angle, length defines duration, and rate defines playback speed.
`void`	`llSetLinkPrimitiveParamsFast(integer link, list rules)` Sets primitive parameters for the linked prim link according to rules with no built-in script sleep delay.

Additional

llParticleSystem — the rules list
- PSYS_PART_FLAGS — bitfield of particle flags, combined with |
- PSYS_PART_EMISSIVE_MASK — particles are full-bright and unaffected by global lighting
- PSYS_PART_RIBBON_MASK — joins emitted particles into a continuous ribbon strip
- PSYS_SRC_PATTERN — the generation pattern, such as PSYS_SRC_PATTERN_EXPLODE (outward in all directions)
- PSYS_SRC_TEXTURE — inventory name or UUID of the particle texture
llSetTextureAnim — the mode flags
- ANIM_ON — must be set to start the animation and cleared to stop it
- LOOP — loop continuously
- SMOOTH — slide smoothly instead of instant frame changes
- ROTATE and SCALE — animate rotation or scale; they cannot be combined
llSetLinkPrimitiveParamsFast — light, glow and text as prim parameters
- PRIM_POINT_LIGHT — local lighting; color in linear space (use llsRGB2Linear)
- PRIM_PROJECTOR — texture, field of view, focus and ambiance of a light projection
- PRIM_GLOW — glow intensity on a face
- PRIM_FULLBRIGHT — full-bright rendering on a face
- PRIM_GLTF_EMISSIVE — the GLTF emission override of a face
- PRIM_TEXT — hover text, equivalent to llSetText

Particle rules

Constant groups ParticleParam 27 ParticleFlag 10 ParticleSourcePattern 5 ParticleBlendFunc 8

Texture animation modes

Constant groups TextureAnimMode 7

See also Category Particles SL Wiki LSL Particles SL Wiki Script library: particlesPlanned Recipe: particle effect presets