Sigmoid Smoother (Flowgraph Node)

Overview

• Node Name: Sigmoid Smoother
• Category: simple
• File: extensions/flowgraph/nodes/math/smoothers/sigmoid.lua

Provides sigmoid-style temporal smoothing with configurable rate limits and acceleration parameters for both increasing and decreasing signals.

Pin Schema

Input Pins

Output Pins

Internals

How It Works

1. On init, a newTemporalSigmoidSmoothing() object is created.
2. If the set pin changes, the smoother state is directly set.
3. If no value is provided, the current smoother state is output.
4. Otherwise, three parameters (rate limit, start accel, stop accel) are selected based on direction.
5. The smoother uses getWithRateAccel(sample, dt, limit, start, stop) for S-curve smoothing.

The sigmoid profile accelerates at the beginning and decelerates at the end of a transition, creating smooth starts and stops.

Lua Example

-- Smooth a UI progress bar with S-curve easing:
-- value = target progress (0-1)
-- dt = frame delta time
-- upRateLimit = 2 (max speed)
-- upStartAccel = 5 (quick start)
-- upStopAccel = 3 (gentle stop)

Key Dependencies

• newTemporalSigmoidSmoothing() - BeamNG sigmoid temporal smoothing primitive
• ui_imgui - displays smoother state in the node editor
• _flowgraph_createNode() - standard flowgraph node registration

Additional Methods

C:checkSetValue()

Node method.

C:drawMiddle(builder, style)

Custom ImGui drawing in the middle section of the node in the editor.

Parameters:

• builder
• style

C:work()

Main work function called each frame/tick when the node is active.

See Also

• Linear Smoother (Flowgraph Node) - Related reference
• Nonlinear Smoother (Flowgraph Node) - Related reference
• Spring Smoother (Flowgraph Node) - Related reference
• FlowGraph Guide - Guide