ZapTo Generates a forked lightning bolt from a given point to the edges of objects in the ToObj input clip, and renders it over a background input. Inputs: ToObj:  The edges of objects in this clip are extracted, and the lightning connects to points along these edges facing towards the starting point. Back:  The clip to use as background.

Parameters:

Surface Points:   Integer,  Default: 10,  Range: 1 or greater.
The number of points along the edges to connect the lightning to. These surface points are divided up amongst the shapes in the ToObj input. If the number of requested surface points is equal to the number of separate shapes in the ToObj input, one lightning fork will connect to each.

Start:   X & Y,   Default: [360 242],  Range: any.
The starting position of the lightning.

Max Dist:   Default: 1,  Range: 0 or greater.
The maximum distance of surface points from the Start position. Edges outside this distance are ignored.

Threshold:   Default: 0.5,  Range: 0 or greater.
The value used to determine the edge locations. Objects darker than this value are ignored. On smooth objects, larger threshold values move the edges inwards to make smaller shapes, and smaller values move the edges outwards. You can use the Show Edges option to view the edge image directly while adjusting this parameter.

Blur To Obj:   Default: 0.025,  Range: 0 or greater.
Blurs the ToObj input clip before finding the edges. This can help remove noise, and reduce the number of separate shapes. You can use the Show Edges option to view the edge image directly while adjusting this parameter.

Show:   Popup menu,  Default: Result.
Selects what the effect will output.

Result:  shows the normal lightning result over the background.

Over ToObj:  shows the lightning over the ToObj input instead of the Back. This can be useful to view while adjusting the Surface Points, Start, and Max Dist parameters.

Edges:  shows the target edge image. This can be useful to view while adjusting the Threshold and Blur To Obj parameters.

Width:   Default: 0.1,  Range: 0 or greater.
The width of the lightning bolts.

Vary Width:   Default: 0,  Range: 0 to 1.
The amount of random variation in the width of the bolts along their lengths.

End Pointiness:   Default: 0.25,  Range: 0 to 1.
Determines how pointed the end of the bolts are. If 0, the entire bolt will have equal width. If 1, the bolts will thin out along their entire length for a pointed end. If it is .5, the bolts will start thinning out half way between the start and end points.

Wiggle Start:   Default: 0,  Range: 0 or greater.
By default the bolts automatically wiggle over time. This parameter provides a starting offset for these bolt perturbations.

Wiggle Speed:   Default: 1,  Range: 0 or greater.
The speed at which the bolts are perturbed automatically over time. To animate changes in speed, set this to zero and animate the Wiggle Start parameter instead.

Jitter Frames:   Integer,  Default: 0,  Range: 0 or greater.
If this is 0, the same random lightning will be used for every frame processed. If it is 1, different random lightning is used for each frame. If it is 2, new random lightning is used for every other frame, and so on.

Rand Seed:   Default: 0.123,  Range: 0 or greater.
Used to initialize the random number generator. The actual seed value is not significant, but different seeds give different random lightning bolts, and the same value should give a repeatable result.

Brightness:   Default: 1,  Range: 0 or greater.
Scales the brightness of the lightning bolts.

Color:   Default rgb: [1 1 1].
The color of the lightning. If you want to keep the lightning bolt itself bright white, you can still affect the perceived color by adjusting the Glow Color instead.

Wrinkle Amp:   Default: 1,  Range: 0 or greater.
Scales the amount of wrinkles in the bolts. Decrease for straighter smoother bolts or increase for more kinky bolts.

Branchiness:   Default: 1,  Range: 0 to 20.
Scales the number of additional bolts that branch from the main bolt. Set this to 0 for basic bolts with no extra branches.

Branch Angle:   Default: 65,  Range: 0 to 180.
The maximum angle of the random branches relative to the bolt they are branching off of. If this is 0 the branches will be more lined up with the main bolt. With larger values the branches will be more perpendicular to the main bolt.

Branch Length:   Default: 0.5,  Range: 0 to 1.
The maximum length of the branches relative to the distance between the Start and End points.

Scale Back:   Default: 1,  Range: 0 or greater.
Scales the brightness of the background before combining with the lightning. If 0, the result will contain only the lightning image over black.

Combine:   Popup menu,  Default: Screen.
Determines how the lightning and glow are combined with the Background.

Screen:  performs a blend function which can help prevent overly bright results.

Add:  causes the lightning to be added to the background. This gives brighter glows over light backgrounds.

Params2:

Start Offset:   Default: 0,  Range: 0 to 1.
The offset from the start point to begin drawing the bolts. This can be useful for animating a lightning strike.

Length:   Default: 1,  Range: 0 to 1.
The length of the bolts, beginning at Start Offset. If less than 1, the bolts will not be drawn all the way from start to end. This can be useful for animating a lightning strike.

Bolts:   Integer,  Default: 1,  Range: 1 to 1000.
The number of independent forked lightning bolts to draw, each connecting the Start position with the edge points.

Glow Parameters:

Glow Bright:   Default: 2,  Range: 0 or greater.
Scales the brightness of the glow applied to the lightning.

Glow Color:   Default rgb: [0.5 0.5 1].
The color of the glow applied to the lightning.

Glow Width:   Default: 0.2,  Range: 0 or greater.
The width of the glow applied to the lightning.

Glow Width Red:   Default: 0.5,  Range: 0 or greater.
The relative red width of the glow.

Glow Width Grn:   Default: 1,  Range: 0 or greater.
The relative green width of the glow.

Glow Width Blue:   Default: 1.5,  Range: 0 or greater.
The relative blue width of the glow.

See Also:

Zap ZapFrom

Sapphire Plug-ins Introduction

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