SpeedSix.Particles (Discreet Box5)
PURPOSE
Provides a comprehensive, general purpose, 2D particle system simulator and renderer. A variety of natural phenomena can be modelled using this, and many interesting effects can be achieved. This system is much more flexible than the specific particle based Monsters (Snow, Rain etc), though those are to be when you want the particular effects they were designed to produce.
A set of tutorial exercises is included to help you get some idea of how this system works. Just reading about it makes it sound unduly complicated! Try the exercises at the end of this chapter and you will understand the principles involved.
INPUT CLIPS
1: Background
Example : Birth
2: Birth
: Particles will only be created within the non-black regions of this clip. Make sure the birth zone covers the region,
Example : Bounce
3: Bounce
: Particles will bounce off the non-black regions of this clip.
Example : Turbulence
4: Turbulence
: Particles will be influenced by the gradients of the luminance in this clip. The particles will flow over the features.
5: Alternative Colours
: Each particle, when born, will take its colour from the corresponding location within this clip.
6: Particle Image
: A particle can be this image! Use with caution as rendering many particles as an image will <i>take some time</i>.
Particles CONTROL PAGE
Kill All Parts (Pushbutton)
Deletes all the current particles ready to start again. This control will be found on several pages to help you quickly see the results of any changes to the birth properties.
Restart+PreRoll (Pushbutton)
Restarts and pre-rolls the particle system for the current value of PreRoll.
Do PreRoll (Pushbutton)
To see further into the evolution of the particles, do another preroll by pressing this button.
PreRoll (Number Min: 1, Max: 1000, Default: 50)
Run the particle system for the specified number of pre-roll frames before generating the first frame of the output clip.
Advance (Pushbutton)
Click to advance system one frame without changing frames or other settings. Useful for checking frame by frame evolution and motion speeds.
Position (Position Default: 0.5,0.5)
Position Var (Number Min: 0.001, Max: 2.0, Default: 0.1)
The particles are born within the region of Position plus and minus Position Var. See also Birth matte, however.
Lifetime (Number Min: 1.0, Max: 1000.0, Default: 150.0)
The average number of frames for which a particle will live. It will definitely be killed after it has lived this number of frames (plus or minus the Lifetime Var below). They may die younger (see Extinction).
Lifetime Var (Number Min: 0.0, Max: 100.0, Default: 5.0)
The actual lifetime of a particle is the average lifetime plus or minus a random number ranging up to LifetimeVar.
Use Birth Matte (Checkbox Default: Off)
On: particles will only be born in the intersection of the birth circle and non-black regions of the images in the birth matte clip you select.
Fecundity (Number Min: 0.0, Max: 10000.0, Default: 100.0)
Fecund Var (Number Min: 0.0, Max: 1000.0, Default: 10.0)
The actual number of particles born at each frame is the average number specified by Fecundity plus or minus a random amount ranging up to the specified Fecundity Variance.
Note: if you are using a birth matte you may not get the full amount as checks are made on the probability of finding a suitable place to create a particle. Without this the particle system could try indefinitely to create the particles and you would not like that!
Scale Fecundity (Checkbox Default: On)
On: when you change your working resolution on the Settings page, the number of particles born is scaled accordingly. Lower resolution equals fewer particles. This is for clarity and speed.
Off: whatever the resolution the same quantities of particles are created.
Extinction (Number Min: 1.0, Max: 1000.0, Default: 150.0)
Extinct Var (Number Min: 0.0, Max: 1000.0, Default: 20.0)
Each particle will gradually fade out as it gets older. Making the extinction twice the lifetime will ensure they do not disappear, but pop off if still in screen.
Seed (Number Min: 0, Max: 999, Default: 127)
Change to have a different selection of particles.
Tutorials (List Box Options: Birth Velocity | Gravity | Friction | Turbulence | Wind1 | Wind2 | Bouncing | Suction1 | Suction2 | Suction3 | Turbulence1 | Turbulence2 | Turbulence3, Default: Birth Velocity)
Work through the /I/BParticles Tutorial/b/i.
Demos (List Box Options: Candy Floss | Fountain | Geyser | Simple Vapour | Smoke | Soft Smoke | Smoke+Wind | Tunnel, Default: Candy Floss)
Select a preset to get you going.
Motion CONTROL PAGE
Kill All Parts (Pushbutton)
Restart+PreRoll (Pushbutton)
Do PreRoll (Pushbutton)
See Particles CONTROL PAGE descriptions.
Use Turbulence Map (Checkbox Default: Off)
Turbulence (List Box Options: Attraction | Direction | Accumulation, Default: Attraction)
Dir Magnitude (Number Min: -500.0, Max: 500.0, Default: 10.0)
Flow Magnitude (Number Min: -500.0, Max: 500.0, Default: 10.0)
These are experimental effects originally written to a beloved customer's specification many moons ago. The effects worked for them, and they may work for you. The 4th input clip is used as a turbulence field which will affect the progress of the particles. Words cannot easily explain what you will see. Try it.
Motion (List Box Options: Motion | Constant | Motion+Constant, Default: Constant)
This is the initial velocity with which each particle moves.
Motion: derives the speed and direction from the motion of the Birth Position. You should set up a movement path for the birth position to see the full effect. With no motion set up, the particles will have no initial movement. This is the same as using Constant with 0.0 Initial Velocity. Use it to eject particles along the path of the motion.
Constant: the motion of the birth position is ignored and only the Initial Velocity value is used.
Motion+Constant: the motion velocity and the initial velocity are combined.
Initial Velocity (Number Min: 0.0, Max: 5000.0, Default: 1000.0)
This is the velocity with which the particles are emitted from the birth position. This is disabled when Motion is selected as it will have no effect.
Vel Scale (Number Min: -5000.0, Max: 5000.0, Default: 100.0)
Used for very extreme initial velocity requirements in Constant mode and to direct the particles in Motion mode. Positive values with Motion will throw the particles in the direction of the movement; negative values throws the particles in the opposite direction to the motion.
Vel Mag Var (Number Min: 0.0, Max: 100.0, Default: 100.0)
A random amount, plus or minus the initial velocity, is added to vary the initial velocity.
Vel Dir (Number Min: 0.0, Max: 360.0, Default: 0.0)
The direction in which the particles are moving, measured in degrees. 0 being East, 90 North, 180 West and 270 South.
Vel Dir Var (Number Min: 0.0, Max: 100.0, Default: 100.0)
At 100.0 percent the particles will travel in all directions. 0.0 they will follow the direction set. And anywhere in-between...
Sink (Checkbox Default: Off)
Sink (Position Default: 0.8,0.8)
Sink Radius (Number Min: 0.0, Max: 2.0, Default: 0.1)
Sink Strength (Number Min: -50.0, Max: 50.0, Default: 5.0)
Strength Rate (Number Min: 0.01, Max: 100.0, Default: 1.0)
Hole Radius (Number Min: 0.0, Max: 1.0, Default: 0.01)
Sink Swirl (Number Min: -10.0, Max: 10.0, Default: 3.0)
Any particles within the sink circle are attracted towards the center with the given [positive] Sink Strength. At the outer circumference the strength is negligible, increasing to the set value as the particle approaches the center. Use the Sink Rate to bias the acceleration of the particles. Values above 1.0 will cause the particles to move more slowly towards the circumference and speed up to the Sink Strength value as they near the centre. Below 1.0 and they start with the Sink Strength which increases as they near the center. Reverse this movement if the Sink Strength value is negative.
When a particle enters the Hole Radius area then it has 'gone down the plughole' and disappears. Add in a Swirl to twist the particles around the center.
Use Bounce Regions (Checkbox Default: Off)
Bounce Rebound (Number Min: -200.0, Max: 200.0, Default: 10.0)
Off: the 3rd input clip is ignored. No bouncing will occur.
On: information in the 3rd input clip deflects the particles as they hit a non black area of this image. The particles bounce of this 'surface' with a Rebound factor. This adds to the velocity of the particle, shooting it off at an angle. The higher the rebound value the more impetus each particle is given and the greater the reaction. This is not extremely scientific but rather artistic license to exaggerate the response. Negative values gives the impression of pouring over the surface rather than bouncing off it. Here the vertical motion is stopped, the horizontal motion continues waiting for gravity to pull on it again.
Forces CONTROL PAGE
Kill All Parts (Pushbutton)
Restart+PreRoll (Pushbutton)
Do PreRoll (Pushbutton)
See Particles CONTROL PAGE descriptions.
Turbulence (Checkbox Default: On)
SwirlDens (Number Min: 0.0, Max: 100.0, Default: 60.0)
SwirlAmp (Number Min: 0.0, Max: 100.0, Default: 1.0)
SwlMaxTim (Number Min: 0.0, Max: 1000.0, Default: 0.0)
For natural swirls and eddies of the air through which the particles move you need turbulence. The Density is the fineness of the turbulence patterns. The lower the Density value the broader the sweeps of turbulence are. High values give rapid changes in direction. The motion can be exaggerated with the Amplitude setting, dramatically forcing the particles around or subtly twisting them as they move. The effect of the turbulence can be built up using Swirl Maximum Time. At 0.0 the particles are influenced by the turbulence immediately. Otherwise it takes that number of frames from birth for the turbulence to build up.
Friction (Checkbox Default: On)
Friction (Number Min: 0.0, Max: 1.0, Default: 0.05)
Friction slows things down. Rubbing against the air and each other, friction will reduce the momentum of the particles,
Gravity (Checkbox Default: On)
Gravity (Number Min: 0.0, Max: 10.0, Default: 0.2)
Grav Angle (Number Min: 0.0, Max: 359.0, Default: 270.0)
At values over 0.0 gravity acts on the particles dragging them in the direction set by the Gravity Angle. A setting of 270.0 degrees is downwards. A natural choice, but varying the angle can bias the movement for artistic purposes.
Multi Directional (Checkbox Default: Off)
Wind (Checkbox Default: Off)
Wind (Position Default: 0.2,0.4)
Wind Target (Position Default: 0.8,0.4)
Wind Spread (Number Min: 0.0, Max: 180.0, Default: 10.0)
Wind Speed (Number Min: 0.0, Max: 180.0, Default: 5.0)
Add in Wind when you want to blow the particles, or some of them, in a specific direction. Drag the wind source to where you want to blow from and the target sets the direction or extent of influence depending on MultiDirectional. When Off the wind has a cone of influence and the wind does not stop blowing at the target location. The Spread governs how far the affect of the wind reaches. When a particle enters the cone, the wind starts to take effect which gradually builds up towards the center of the cone, and then dies away again. Turn MultiDirectional On and the wind blows outward from the center, gradually loosing speed as it reaches the target perimeter. Speed is how fast the wind is blowing. It can be nice to animate this to give gusts.
Flow Scale Speed (Number Min: 10.0, Max: 500.0, Default: 100.0)
If the motion you have set up is too fast or slow then use this global speed change control to adjust the pace of the particles. It will not change any of your set values, but scales them appropriately behind the scenes for you.
Note: this will not affect Turbulence Map options.
Look CONTROL PAGE
Kill All Parts (Pushbutton)
Restart+PreRoll (Pushbutton)
Do PreRoll (Pushbutton)
See Particles CONTROL PAGE descriptions.
Init Dens (Number Min: 0.0, Max: 100.0, Default: 100.0)
Condensation (Number Min: 0.0, Max: 100.0, Default: 100.0)
The density of each particle at birth can be reduced and then the rate of condensation, or 'solidifying' is applied. Think of smoke, at the source you hardly see it until, as it cools it becomes more visible, then turbulence dissipates it. Changing the Condensation will have an immediate effect on all the particles as it is based on the time each particle has been alive. To see an Initial Density change you need to re-run the sequence.
ColourVar (Number Min: 0.0, Max: 100.0, Default: 0.0)
MonoVar (Number Min: 0.0, Max: 100.0, Default: 0.0)
Initial Colour (Colour Box Default: white)
Each particle can take its colour from the colour box which is then changed by the Colour Variance and the saturation by the Monochrome Variance. Thus you can have various colours for your particles if you feel like it.
Fade (List Box Options: Col+Dens | Colour | Density, Default: Col+Dens)
Choose the compositing mode you prefer. Density will make the most use of Density, Condensation and Extinction factors. Colour on its own, the least.
Particle (List Box Options: Point | Soft Point | Streak | Lump | Star | Image, Default: Streak)
Chose the style of particle you want to draw with.
Point: a single pixel.
Soft Point: this softened pixel will need a great many particles to be seen, but probably the nicest if you have the time.
Streak: pixels drawn between the current and previous position to give directionality to the movement. Often helpful to see exactly what is happening.
Lump: soft blobs of a given size.
Star: well they are stars!
Image: the last input clip can be used as an image to be drawn wherever a particle is needed. When it is read in, the image area is clipped to a bounding box based on the image being on a black background. The complete image can be used if needed.
Note: once read in and loaded it is not replaced on processing a clip.
Streak Scale (Number Min: 0.1, Max: 1000.0, Default: 100.0)
When Streak is selected the 'tail' can be scaled to exaggerate the motion.
Lump Rad (Number Min: 1.0, Max: 40.0, Default: 30.0)
Lump RadVar (Number Min: 0.0, Max: 100.0, Default: 0.0)
When lump, star or image is used they are scaled to the Lump Radius plus or minus a random Radius Variance.
Use Image Colours (Checkbox Default: Off)
A particle's colour is set using it's birth location in the 5th input clip.The Box colour and variances are ignored.
Image (List Box Options: Stamp | Punch Front&Back | Punch Back, Default: Stamp)
Using the 6th input as a particle Image chose the method of compositing the shape in the scene.
Stamp: replaces the background.
Punch Front & Back: uses the luminance of the image to composite it into the scene.
Punch Back: uses the luminance to add it into the scene.
Note: The aspect ratio of this input clip should match the background aspect ratio to avoid distortion.
Reacquire (Pushbutton)
The 6th input need only be one frame. Currently this effect does not reload a new image for each frame in the sequence. Once loaded it is used throughout. If you change the input to the 6th clip nothing will happen until you activate the Reacquire button. The old image is then replace with the new. Currently alive particles will now be drawn with the new image.
Note: if you want this to be handled on a frame to frame update basis please email support@speedsix.com