Spline Flow Mapper

Input connectors

Spline Coords ColorThe coordinates of the input splines’ points encoded in the RGBA channels of a color image:
    R - X position
    G - Y position
    B - Height
    A - Packed data:
        * Sign: Spline is closed (negative) or open (positive);
        * Absolute value: Thickness + 1.

Spline Data ColorAdditional data of the input splines encoded in the RGBA channels of a color image.
    R - Tangents X
     G  - Tangents Y
     B  - Unused
     A  - Unused

Spline Amount IntegerThe number of input splines.

Attenuation Profile Curve GrayscaleThe image describing a curve using the values of its first row of pixels.
When the Attenuation Profile parameter is set to Input Profile Curve, this input is used to control the gradient ramp for the attenuation of the flow vector data drawn along the spline.
You may use a Curve node to author the curve.

Output connectors

Output ColorThe output flow map encoded in a color image.

Parameters

Segments Amount IntegerSplines are simplified into segments before vector flow data traverses them.
A higher amount of segments results in a smoother flow mapping along curves.

Mode IntegerThe method of selecting the splines along which vector flow data should be drawn:
- Draw Spline List: All the splines in the input list are used;
- Draw Single Spline: Only the spline with the specified index is used;
- Draw Spline Range: Only the splines which index is included in the specified range are used.

Draw Spline Index Integer (Available when ‘Mode’ is set to ‘Draw Single Spline’)The index of the spline along which vector flow data should be drawn.

Draw Spline Range Integer2 (Available when ‘Mode’ is set to ‘Draw Spline Range’)The range of indexes for the splines along which vector flow data should be drawn.

Thickness Mode IntegerThe method of setting the thickness of the drawn vector flow data
- Manual: Set the thickness explicitly with an arbitrary value;
- From Spline: Use the thickness of the spline.

Thickness Float (Available when ‘Thickness Mode’ is set to ‘Manual’)The arbitrary value for the thickness of the vector flow data drawn along the splines.

Thickness Multiplier Float (Available when ‘Thickness Mode’ is set to ‘From Spline’)A global multiplier for the thickness of the vector flow data drawn along the splines, when that thickness it driven by that of the splines.

Direction IntegerThe direction of the vector flow in relation to the spline.
- Tangent: Use the spline’s tangent vector;
- Normal: Use the spline’s normal vector;
- Normal Mirrored: Use the mirrored version of the spline’s normal vector.

Flip Direction BooleanInverts the direction of the splines, which also impacts the direction of the flow vector.

Attenuation Profile IntegerThe gradient ramp used to draw the attenuation of the flow vector data drawn along the spline:
- Linear: Use a linear gradient ramp;
- Gaussian: Use a gaussian gradient ramp
- Input Profile Curve: Use the curve provided to the Attenuation Profile Curve input as a gradient ramp.

Start Attenuation BooleanAdds a half-circle at the start of the spline. The half-circle uses the same attenuation as the spline.

End Attenuation BooleanAdds a half-circle at the end of the spline. The half-circle uses the same attenuation as the spline.

Spline Height Attenuation FloatThe intensity of the flow vector data drawn along the spline is multiplied against the spline’s height, where the drawn data fades to the background’s neutral (0.5, 0.5, 0) color as the height gets closer to 0.

Non-Square CorrectionBooleanAdjust the points’ positions and thickness to retain the spline shape in non-square resolutions.
This also impacts uniform distribution.

Examples