SpeedSix.Snow   (Discreet Box4)



PURPOSE

Snow simulation using particles.
Snow is a time based effect; the characteristics a particle is born with will evolve over time (every frame generated) to create the effect.

snowa.jpg snowb.jpg



INPUT CLIPS

 1: Background Clip
 2: Settle Clip : The snow can settle on non black areas within this clip. However you do need to have a static shot for this to suceed.



Snow   CONTROL PAGE

Restart Snowstorm  (Pushbutton)
     Restarts the snow sequence using the current settings. This control will be found on several pages to help you quickly see the results of any changes to the birth properties of each snow flake.

Restart+PreRoll  (Pushbutton)
     Restarts and pre-rolls the snow for the current value of PreRoll

Do PreRoll  (Pushbutton)
     To see further into the evolution of the particles, do another preroll.

PreRoll  (Number  Min: 1, Max: 1000, Default: 150)
     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 the snow one frame without changing frames or other settings. Useful for checking frame by frame evolution and motion speeds.

Left  (Position  Default: 0.2,0.8)

Right  (Position  Default: 0.8,0.8)

Position Var  (Number  Min: 0.0, Max: 2.0, Default: 0.02)
     The region within which snow particles will be created.

Lifetime  (Number  Min: 1.0, Max: 1000.0, Default: 200.0)
     How long each snow particle drop will live for.

Density  (Number  Min: 0.0, Max: 10000.0, Default: 20.0)
     How many smoke particles will be created each frame.

Initial Velocity  (Number  Min: -20.0, Max: 20.0, Default: -3.0)
     The initial speed of a snow particle. The direction is always in the direction of gravity.

Velocity Var  (Number  Min: 0.0, Max: 100.0, Default: 50.0)
     Size of random variations in initial speed of a snow particle. The direction is always in the direction of gravity.

Snow Settle  (Checkbox  Default: Off)
     Allows the snow to settle on non-black areas of the settle clip.

Probability  (Number  Min: 0.0, Max: 100.0, Default: 50.0)
     How likely it is that the snow will settle.

Bias  (Checkbox  Default: Off)
     Turn on the bias to wet or dry snow feature.

Dry Snow  (List Box  Options: Wet | Dry, Default: Wet)
Select the type of snow your prefer.
On: smaller flakes will fall more quickly.
Off: Larger flakes will fall more quickly.
Size Bias  (Number  Min: 1.0, Max: 20.0, Default: 1.0)
     The speed the snowflakes can fall at varies with size. At 0.0 there is no bias. As the value increases the larger flakes will fall faster than the smaller flakes. But if Dry Snow is On, then the small flakes fall faster than the larger flakes.

Demos  (List Box  Options: Blizzard | Base | Fine | Heavy | Avoid | Divert | Glitter | Pink | Vomit | Amorphous | Pastel | Stream, Default: Blizzard)
Select a preset to get you going.


Forces   CONTROL PAGE

Restart Snowstorm  (Pushbutton)
Restart+PreRoll  (Pushbutton)
Do PreRoll  (Pushbutton)
     See start descriptions.

Turbulence  (Checkbox  Default: On)
     Turn on the turbulence feature.

SwirlDens  (Number  Min: 0.0, Max: 100.0, Default: 60.0)
     How many bumps there are in the atmosphere from one edge of the frame to the other. The snow swirls as it runs into these bumps.

SwirlAmp  (Number  Min: 0.0, Max: 100.0, Default: 1.0)
     How powerful the bumps in the atmosphere are.

SwlMaxTim  (Number  Min: 0.0, Max: 100.0, Default: 0.0)
     Frames over which the swirl amplitude builds up to its maximum value (set by SwirlAmp).

Friction  (Checkbox  Default: On)
     Turn on the friction feature.

Friction  (Number  Min: 0.0, Max: 1.0, Default: 0.05)
     Controls the frictional force of the atmosphere on the snow as a percentage of the snow velocity lost per frame. Slows the snow down.

Gravity  (Checkbox  Default: On)
     Turn on the gravity feature.

Gravity  (Number  Min: 0.0, Max: 10.0, Default: 0.2)
     Scales the strength of the gravitational force.

Grav Angle  (Number  Min: 0.0, Max: 359.0, Default: 270.0)
     Controls the angle at which gravity acts, measured in degrees clockwise from due East. The default [270.0] is towards the bottom of the image.

Multi Directional  (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)
     The wind when active, and not Multi-directional, blows from the Source to the Target within a cone defined by the WindSpread with the strength of the WindSpeed. Turn on Multi-Directional and the wind will blow equally in all directions.

Wind  (Checkbox  Default: Off)
     Turn on the wind feature.



Look   CONTROL PAGE

Restart Snowstorm  (Pushbutton)
Restart+PreRoll  (Pushbutton)
Do PreRoll  (Pushbutton)
     See start descriptions.

ColourVar  (Number  Min: 0.0, Max: 100.0, Default: 0.0)
     Random variation in the colour of the snow particles.

MonoVar  (Number  Min: 0.0, Max: 100.0, Default: 0.0)
     Random variation in the brightness / density of the snow particles.

Snow Colour  (Colour Box  Default: white)
     Bases snow colour.

FadeMode  (List Box  Options: Col+Dens | Colour | Density, Default: Density)
This control affects how the snow particles composite with one another and with the background image and has a great effect on the final appearance.
Look  (List Box  Options: Point | Streak | Flake | Star, Default: Flake)
How the snow particles are drawn.
Size  (Number  Min: 1.0, Max: 20.0, Default: 4.0)
     When in Flake mode this is the maximum size a snow flake can be.

Size Var  (Number  Min: 0.0, Max: 100.0, Default: 100.0)
     How varied the flake sizes are. At 0.0 they will all be of a similar size.



Glints   CONTROL PAGE

Glints  (Checkbox  Default: Off)
     Turn on the glint feature.

Glint Target  (Position  Default: 0.1,0.5)

Glint  (Position  Default: 0.9,0.5)

Glint Prob  (Number  Min: 0.0, Max: 100.0, Default: 50.0)
Glint Zone  (Number  Min: 0.0, Max: 180.0, Default: 90.0)
Glint Tight  (Number  Min: 0.0, Max: 1000.0, Default: 30.0)
Glint Colour  (Colour Box  Default: white)
     With the glint feature on, the snow can catch the light as it passes through the region defined by the glint parameters.

Colour  (List Box  Options: Box Colour | Snow Colour | Random Colour, Default: Box Colour)
The choice of the colour source for the glints.
Box Colour: User selected single colour.
Snow Colour: The colour is taken from the snowflake.
Random Colour: A randomly chosen colour.

Index