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Particles system in 2.46

Tutorial #1 - Basics

Blend file: ParticleTut1.blend

Setup

Create a Plane object and add an Emitter particle system with the following settings.

Physics -> Newtonian -> Normal 2.0
Visualization -> Draw -> Enable Vel, Size, Num
Extras -> Size 0.1 (Affects Visualization -> Draw -> Size)

Play the timeline. You will notice that the particles will emit in a ordered manner. All the particle sizes are same.

Now, we will change both.

Particles -> Emit From -> Random

Emits particles in random order of elements

Extras -> Rand 1.0

Gives particle size a random variation

Displaying the Unborn/Died particles

By default, the particles are shown only when they are born. We can change this behavior by enabling the

Visualization:Render -> Unborn button, 

so that at the beginning all unborn particles are displayed.

Also by default, particles that are dead are removed from display. If you wish to see the dead particles, enable the

Visualization:Render -> Died button.

NOTE: The 'Died' option does not make any difference if the Looping of particles is enabled. (SEE BELOW)

Looping the particles life

If you want the dead particles to be reborn again, enable the Extras:Time -> Loop button. Now the dead particles are reset to unborn state and eventually are born again.

Tweaking the particle simulation

With the current settings, each particle lives for 2 Blender units, before it dies (the lifespan of the particle was set to 25).

Now if you want to scale the life of the particle, say it needs to be alive for 4 Blender units: we can do so by increasing the default value of Extras -> Tweak attribute (1.0) to 2.0.

Exercise:

• Try with a 'Tweak" value of 0.5