How are real particles emitted

Blender Documentation: Particle Settings

This page refers to
Blender v2.41
There is one from this side
more recent version

Create a scene with a single plane in plan view (Num 7). This plane becomes the particle emitter. A surface here has the advantage that the surface normal determines the direction in which the particles are emitted. With the level selected, switch to Physics Sub-context of the Object Context (F7 one or two times). Click the button NEW on the Particles Panel. The particle settings are now displayed (illustration 1). These will all be discussed individually in a moment, but a simple example first.

Simplest example [edit]

Just leave all the settings as they are normal on the Particle Motions Increase Panel to 0.1. Rotate the 3D view slightly so that you are looking at the plane at an angle. Make sure the mouse is over a 3D window and press Alt-A. You will see a flow of particles emanating from the surface in the direction of the surface normal.

Congratulations - you have just created and animated your first particle system.

Now change the parameters: Amount on 10,000, that Life under Emit to 100, Random under Velocity to 0.1, Force-Z to -1.0. The particles should be emitted upwards and then fall downwards (fountain).

The particle settings [edit]

Illustration 1: The settings for the particle effect

The particle settings are divided into different blocks in the panels, we will proceed in the corresponding order in the description.

  • Delete: The particle effect is deleted.
  • Recalc All: After changes to the particle system, this must be recalculated. Usually this happens automatically, sometimes you have to trigger the recalculation.
  • Static: In the case of static particles, the entire service life is displayed at once. They have slightly different material settings, these are discussed in the Static Particles section.

Emit [edit]

  • Amount: The total number of particles produced. You can generate 100,000 particles per emitter. Please note that this is the total number including all daughter generations, if the daughter generations require many particles, no particle at all may be emitted.
  • Sta / End: Start and end frame of the particle animation.
  • Life: The lifetime of the particles in frames. In the case of static particles, this corresponds to the length of the particles.
  • Disp: How many percent of the particles should be displayed in the 3D window. This is particularly important with static particles, as otherwise the work will be slowed down a lot.

From [edit]

These options control from which parts of the mesh the particles should be emitted.

  • Verts: Particles are emitted from the vertices. If you use the options for even distribution of the emission, the particles only emanate from the faces, even if Verts is activated.
  • Faces: Particles are emitted from the faces.
  • Edge: "real" coincidence.
  • Even: even distribution based on the size of the faces. This means that the density of the particles is independent of the size of the faces.
  • P / F: maximum number of particles per face when one Not the Even Distribution used. 0 uses the default settings.
  • VGroup: The particles are only emitted by vertices / faces that are in this vertex group. This can do two things:
    1. Limitation of the emission to certain parts of the mesh.
    2. Control of the particle density via weight painting. Vertices with a Weight of 1 emit full, vertices with one Weight of 0 do not emit.

The best way to use weight painting is to do the following: Switch to the Editing Buttons (F9). Switch to the Edit mode. Select the desired vertices and create a new vertex group (see Edit Mode). Assign the selected vertices to the vertex group (Assign). The vertex group should have a Weight of 1 have.

Switch to the Weight paint Mode. On the now appearing Paint Panel select the one you want Weight and paint with the "brush" on the mesh. Blue corresponds to one Weight from 0, red one Weight from 1.

Now write the name of the vertex group on the Particles Panel in the field VGroup a (don't confuse on the Particle Motion There is also a panel VGroup).

Figure 2: Weight painting to control particle emissions.

Display [edit]

These options control the display of the particles, i.e. how they are rendered.

  • Material: The material for the particles. Mesh and particles can use different materials, and you can quickly switch between different materials.
  • Mesh: The mesh is also rendered, otherwise only the particles.
  • Unborn: Typically, particles are only shown during their lifetime. With Unborn the particles are rendered beforehand. There is a nice video on the release notes page (see below).
  • Died: Particles are rendered after they finish. But then you no longer follow force fields or guides.
  • Vect / VectSize: Basically, halos and objects move with the particles, but they do not take over their rotation. Is Vect turned on, you also take over the rotation of the particles. VectSize affects the size of halos when Vect is employed. Has on objects VectSize no impact. In the case of static particles, the Vect Option also the "strands" of the particles in the 3D window.

Children [edit]

Each "dying" particle can create new particles. In the case of dynamic particles, however, the lifetime (Life) be shorter than the animation duration, otherwise there will be no new generation. You also have to influence the particle movement (Random Parameters), if the daughter generations move in the same direction as the parent generation, you will not be able to recognize the children.

  • Generation: The respective generation for which the settings below are made. generation 0 is the initial generation.
  • Num: The number of daughter particles produced by each "dying" particle. Note the total number of particles (Amount)! If only 100 particles are to be generated in total, but the number of child particles is already 100, no particle will be emitted at all. Note: This button has a tooltip that I don't understand completely, don't let that confuse you.
  • Prob: The probability that a dying particle will have offspring.
  • Life: The lifespan of the next generation.
  • Mat: The material for the next generation. A rising rocket can explode in a different color, or a brown stem can have green rungs.

All other settings are adopted from the parent generation (if applicable). So it is unfortunately not possible to apply different force fields to different generations. The Keys Parameters on the Particle Motion The panel must be large enough (30 to max.), Even if this is memory-intensive. Otherwise the generations are not connected, which of course looks strange with static particles.

For an example, see the Particle Fireworks section.

Particle Motion [edit]

The movement of the particles is controlled on this panel. Their speed of emission, the direction in which they are emitted and the order in which they are emitted. Unfortunately, you cannot differentiate between the parent and daughter generation, even if they use different materials. All texture settings always refer to the material of the parent generation.

  • Keys: The path of the particles is calculated with a certain number of key positions. Complicated forms of movement may require many key positions. However, 100,000 particles in 50 positions require around 150 MB of memory. For static particles in particular, it is important to have a sufficient number of key positions calculated. In the case of dynamic particles, the Keys Number of the speed of the following generations. At a Keys The value of 50 is that all generations are equally fast Keys If the value is smaller, the daughter generations are accelerated at one Keys If the value is greater than 50, the daughter generations are slower.
  • Example: There is no linear interpolation between the key positions, but rather with B-splines, which creates a slightly smoother movement.
  • Seed: Random numbers are often not really random, a "randomly" generated series of numbers reads the same the second time as the first time. By Seed the random numbers get an additional variation.
  • RLife: The lifespan is varied randomly (0.0 to 2.0).

Velocity [edit]

  • Normal: The particles get a start speed in the normal direction (-2.0 to 2.0). If there is no area, the local vertex coordinate is used.
  • Object: If the particles are not emitted from a stationary object but from a moving object, the particles can take over the speed and direction of the object (-1.0 to 1.0). Otherwise the object will move through a static cloud of particles. This can be intentional, as smoke, for example, stops practically immediately due to the high air resistance. In space, a cloud of smoke would move unchecked with the object.
  • Random: The particles get a random starting speed (both by amount and by direction). You absolutely need this parameter so that the daughter generations move in a different direction than the parent generation.
Figure 3: Start speed based on the texture.
Figure 4: The speed settings for Figure 3.
  • Texture: The extent to which the texture in the selected texture channel gives the particles a starting speed. White means high speed, black means low speed (Figure 3 and 4). The texture number refers to the material number under Display. See also the parameters Int, RGB and Degree.
  • Damping: Brakes the particles like a movement in a viscous liquid.
  • VGroup: This vertex group allows you to control how strong the particles are through the options on the Particle Motion Panel can be influenced. To do this, proceed exactly as described for the particle emission.
  • Int / RGB / Grad: These three buttons are mutually exclusive.
    • Int: Uses the intensity of the texture as a factor for that Force.
    • RGB: The color of the texture directly affects the speed of the particles. R the X, G the Y and B the Z component of the speed.
    • Degree: A speed vector is calculated from irregularities in the texture using a mathematical process. The more irregular the texture, the more turbulent the movement of the particles becomes. A Cloud Texture, for example, gives a nice, turbulent effect. In order for this effect to be visible, the number of Keys be raised.
  • Nabla: The size of the area on which the texture for irregularities Degree is examined. Is Nabla too small, nothing happens with a very even texture, if it is too big, the effect of Degree may be too blurred.

Force [edit]

A continuous force, e.g. gravity or wind. Other ways of influencing particles after they have been emitted can be found in the section Controlling Particle Movement.

Texture emission [edit]

The texture that can be set here influences the order in which dynamic particles are emitted. It has no influence on static particles, since these are all emitted at the same time anyway. Dynamic particles are otherwise emitted pseudo-randomly from different places. A burning process can be simulated, for example, with a texture-controlled sequence.

  • TexEmit: Turns the texture-controlled order on or off.
  • Tex: Selects the texture number.

Changes to the parameters seem to have no effect

Use the button often Recalc All. Changes to the textures, for example, always have to be recalculated before they can be displayed.

Links [edit]

Release notes for version 2.40, new particle options
The original, English-language template of this text