We’ll cover a general introduction about Blender’s particle system; how to use it, when to use it, how useful it is on both small scale and large scale projects, and an overview of its implications. In this article, I’ll also discuss how to use the particle system to instance objects
These are just but very few examples of what can really be achieved with the particle system, there’s a vast array of possibilities out there that can be discovered. But I’m hoping with these examples and definitions, you’ll find your way through the wonderful world of visual effects with the particle system.
If you remember watching Blender Foundation’s Big Buck Bunny, it might not seem as a surprise to you that almost the entire film is filled up with so much particle goodness. Thanks to that, great improvements have been made to Blender’s particle system.
As compared to my previous articles, this one uses Blender 2.5, the latest version of Blender which is currently in Alpha stage right now but is fully workable. However, in this article I wouldn’t be telling you what each of the button would do since that would take another article in itself and might deviate from an introductory approach. If you wanted to know more in-depth information about the whole particle system, you can check out the official Blender documentation or the Blender wiki. There had been great improvements on the particle system and now is the right time to start trying it out.
So what are you waiting for? Hop on and ride with me in this journey!
You can watch the video here.
Before we begin with this article, it’s vital to first determine our requirements before proceeding on the actual application. Before going on, we need to have the following:
- Latest Blender 2.5 (you can grab a copy at http://www.blender.org or http://www.graphicall.org)
- Adequate hard disk space
- Decent processor and graphics card
What is a Particle System and where can we find it in Blender?
A particle system is a technique in Computer Graphics that is used to simulate a visual effect that would otherwise be very difficult and cumbersome if not impossible to do in traditional 3D techniques. These effects include crowd simulation, hair, fur, grass, fire, smoke, fluids, dust, snowflakes, and more.
Particle Systems are calculated inside of your simulation program in several ways and one of the most common ones is the Newtonian Physics calculation which regards forces like wind, magnetism, friction, gravity, etc. to generate the particle’s motion along a controllable environment. Properties or parameters of particle systems include: mass, speed, velocity, size, life, color, transparency, softness, damping, and many more. Particle’s behavior along a certain span of time are then saved and written on to your disk. This process is called caching, which enables you to view and edit the particle’s behavior within the timeframe set. And when you’re satisfied with the way your particles act on your simulation space, you can now permanently write these settings to the disk, called baking. Be aware that the longer your particle system’s life is and the greater the number, the more hard disk space it uses, so for testing purposes, it is best to keep the particles number low, then progressively increase them as needed.
Particle mass refers the natural weight (in a gravitational field) of a single particle object/point, where higher mass means a heavier particle and a lower mass implies a lighter particle. A heavy particle is more resistant to external forces such as wind but more reactive to gravitational force as compared to a lighter particle system which is a direct opposite.
Particle speed/velocity refers to how fast or slow the particle points are being thrown or emitted from their source within a given time. They can be displaced and controlled in the x, y, or z directions accordingly. A higher velocity will create a faster shooting particle (as seen in muzzle flares/flash) and a lower one will create slower particle shots.
Size of the particles is one of the most important setting when using a particle system as object instances, since this will better control the size of the objects on the emitting plane as compared to manually resizing the original object. With this option, you can have random sizes which will give the scene a more believable and natural look and offcourse, an easier setup as compared to creating numerous objects for this matter.
Particle life refers to the lifespan of the particles, for how long they will be existent until they disappear and die from the system. In some cases, having a large particle life is useful but it can have some speed drawbacks on your machine. Imagine emitting one million particles within 5 seconds where only half of it is relevant within the first few seconds. That could mean 500,000 particles cached is a sheer waste and rendering your machine slower. Having smaller particle lives sometimes is also useful especially when you’re creating small scale smoke and fire. But all these really depend on the way you setup your scenes. Play around and you’ll find the best settings that suit your needs.
Note though that in Blender, only Mesh objects can be particle emitters (which is simply rational for this purpose). You can modify the size and shape of the mesh object and the particle system reacts accordingly. The direction from which particles are emitted is dictated by the mesh normals, which I will discuss along the way.
In Blender 2.5, we can find the Particle System by selecting any mesh object and clicking the Particles Button in the Properties Editor, as seen in the screenshot. Later, we’ll add and name particle systems and go over their settings more closely.
Blender 2.5’s Particle System
What are the types of Blender particle system?
Currently, there are only two types of particle systems in Blender 2.5, namely Emmiter and Hair. With few on the list, these two have already proved to be very handy tools in creating robust simulations.
Particle System Types
Let’s begin by learning what an Emitter Type is. Aside from the fact that the term emitter is used to define the source of the particles, the emitter type is one different thing on its own.
The Emitter, being the default particle type, is one of the most commonly used particle system type. With it you can create dust, smoke, fire, fluids, snowflakes, and the like. Inside Blender, make the default cube a particle emitter with the type set as Emitter. Leave the default settings as they are and press ALT+A in the 3D Viewport to playback the animation and observe the way the particles act in your observable space, that is, the 3D space that your object is in. During the playback process, the particle system is already caching the position of the particle points in your space and writing these on to the disk. Naturally, this is how the emitter type will act on our space, with a slight pulse from emitter then it drops down as an effect of the gravity. That pulse is coming from the Normal value which tells how strong the points are spurted out until they get affected by external forces. There’s more to the emitter type than there seems to be, so don’t hold back and keep changing the settings and see where they lead you to. And if you can, please send me what you got, I’d be very pleased to see what fun things you came up with.
Leaving from the default settings we had awhile back, change your current frame to 1 (if it is not yet set as such) then let’s change the type from Emitter to Hair. Instantly, you’ll notice that strands come bursting out of our default mesh. This is the particle hair’s nature, whichever frame you are in now, it will stay in the same frame, regardless of any explicit animation you add in. As compared to the Emitter type, Hair doesn’t need to be cached to see the results, it’s an on-the-fly process of editing particle settings. Another great advantage of the hair type over the emitter type is that it has a dedicated Particle Mode which enables you to edit the strands as though you were actually touching real hair. With the hair type, you can create systems like fur, grass, static particle instances/grouping, and more.
Basic and Practical Uses of the Particle System
Now let’s on the real business. From here on, I’ll approach the proceeding steps in a practical application manner. First, let’s check some of the default settings and see where they lead us.
Fire up a fresh Blender session by opening up Blender or by pressing CTRL+N (when you already have it open from our steps awhile ago).
Fresh Blender 2.5 Session
Delete the default cube and add in a Plane object.
Adding a Plane Primitive
Position the camera’s view such that the plane is just on top of the viewing range, this will give us more space to see the particles falling.
Adjusting the View
Select the Plane Mesh and in the Particle Buttons window, add a new Particle System and leave the default values as they are. In the 3D Viewport, press ALT+A to play and pause the animation or use the play buttons in the Timeline Window. Pick a frame you’re satisfied with, any will do right now.
New Particle System
Next, add a new material to the Plane Mesh and the Particle System. Activate the Material Buttons and add a new material, then change the material type from Surface to Halo. Halos is a special material type for particles; they give each point a unique shading system compared to the Surface shaders. With halos, you can control the size of the particles, their transparency, color, brightness, hardness, textures, flares, and other interesting effects. With just the default values, let’s render out our scene and see what we get.
Right now, this doesn’t look too pleasing, but it will be once we get the combinations right. Next, let’s try activating Rings under the halo menu, then Lines, Star, and finally a combination of the three. Below are rendered versions of each and their combination.
Additional Options for Halo
Halo with Rings
Halo with Lines
Halo with Star
Halo with Rings, Lines, and Star
Just by altering the halo settings alone, we can achieve particle effects like pollen dust as seen in the image below where the particle effect was composited over a photo.
Particle Pollen Dust