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Second Life Creation

llMakeExplosion

Deprecated
void llMakeExplosion(integer Particles, float Scale, float Velocity, float Lifetime, float Arc, string Texture, vector Offset)

Make a round explosion of particles. Deprecated: Use llParticleSystem instead.

Make a round explosion of particles using texture from the objects inventory. Deprecated: Use llParticleSystem instead.

Parameters
Particles (integer)
Scale (float)
Velocity (float)
Lifetime (float)
Arc (float)
Texture (string)
Offset (vector)
Technical Details
  • Return Type: void
  • Energy: 10
  • Sleep: 0.1s

Emulation with llParticleSystem

Section titled “Emulation with llParticleSystem”

Beginning in 1.14, the simulator uses llParticleSystem to emulate legacy llMakeExplosion particles. Here’s a working implementation:

fakeMakeExplosion(integer particle_count, float particle_scale, float particle_speed,
                 float particle_lifetime, float source_cone, string source_texture_id,
                 vector local_offset)
{
    //local_offset is ignored
    llParticleSystem([
        PSYS_PART_FLAGS,            PSYS_PART_INTERP_COLOR_MASK | PSYS_PART_INTERP_SCALE_MASK | PSYS_PART_EMISSIVE_MASK | PSYS_PART_WIND_MASK,
        PSYS_SRC_PATTERN,           PSYS_SRC_PATTERN_ANGLE_CONE,
        PSYS_PART_START_COLOR,      <1.0, 1.0, 1.0>,
        PSYS_PART_END_COLOR,        <1.0, 1.0, 1.0>,
        PSYS_PART_START_ALPHA,      0.50,
        PSYS_PART_END_ALPHA,        0.25,
        PSYS_PART_START_SCALE,      <particle_scale, particle_scale, 0.0>,
        PSYS_PART_END_SCALE,        <particle_scale * 2 + particle_lifetime, particle_scale * 2 + particle_lifetime, 0.0>,
        PSYS_PART_MAX_AGE,          particle_lifetime,
        PSYS_SRC_ACCEL,             <0.0, 0.0, 0.0>,
        PSYS_SRC_TEXTURE,           source_texture_id,
        PSYS_SRC_BURST_RATE,        1.0,
        PSYS_SRC_ANGLE_BEGIN,       0.0,
        PSYS_SRC_ANGLE_END,         source_cone * PI,
        PSYS_SRC_BURST_PART_COUNT,  particle_count / 2,
        PSYS_SRC_BURST_RADIUS,      0.0,
        PSYS_SRC_BURST_SPEED_MIN,   particle_speed / 3,
        PSYS_SRC_BURST_SPEED_MAX,   particle_speed * 2/3,
        PSYS_SRC_MAX_AGE,           particle_lifetime / 2,
        PSYS_SRC_OMEGA,             <0.0, 0.0, 0.0>
        ]);
}

Known Discrepancies

Section titled “Known Discrepancies”

When migrating from llMakeExplosion to the llParticleSystem emulation, be aware of these differences:

  1. Particle Lifetime: The original llMakeExplosion had random particle lifetime, which cannot be created in the current particle system via a single call
  2. Particle Growth: The original had continual particle growth throughout its lifetime, ending well past the 4m limit of the current system on long-lived particles
  3. Arc Orientation: The ‘arc’ parameter in the original oriented along the X axis, while the current particle system’s angles orient along the Z axis
  4. Value Scaling: Several values are not taken ‘verbatim’ in the original particle system (velocity is not m/sec, and particle count may vary), approximated via basic divisors
  5. Local Offset: There is no way to duplicate the offset from the old functions within the new particle system

See Also

Section titled “See Also”