Math Step performs parametric shaping operations between two values. While the standard "Math" node offers basic arithmetic, this node focuses on Thresholding and shaping. It provides several response curves: from hard binary steps (0 or 1) to soft, organic transitions (Smoothstep) and signal generation (Pulse). It also includes Smooth Minimum/Maximum blending, making it essential for continuous value shaping and SDF (Signed Distance Field) logic.
Usage & Behavior
Shape Logic: Practical Applications
Use this node to define edges, isolate specific values, or blend shapes together.
Input 1: Threshold (0.5)
Mixer: Noise / Gradient
The standard "Greater Than" logic. Use this to turn soft gradients into binary black/white masks. Perfect for creating holes, alpha cutouts, or turning a smooth noise into distinct islands.
Input 1: Center Position
Input 2: Band Width
Instead of just cutting off values, Pulse isolates a specific range. It returns white only when the input is close to the Center. Use this to draw topographic lines on terrain or "scan lines" on a sci-fi shield.
Input 1: Shape A (Distance)
Input 2: Shape B (Distance)
Standard math creates sharp, unnatural intersections when shapes overlap. Smooth Min blends the values together with a liquid-like fillet. Essential for Signed Distance Field (SDF) modeling or merging procedural masks organically.
This is your primary tool for remapping ranges. Use Smoothstep to turn a linear gradient into a soft mask with eased edges. Use Pulse to extract a specific "band" of values (isolines). Use Smooth Min to merge two shapes together organically without sharp intersections.
Key Features
- 8 Shaping Functions: Covers everything from hard logic to organic blending.
- Vector Support: Processes RGB channels simultaneously.
- Signal Generation: Creates periodic pulses and trains without complex math chains.
Cheat Sheet: Step Modes
Select the mode based on the desired transition curve:
- STEP: Binary cutoff. Returns 0 if $Val < Edge$, else 1.
- LINEAR STEP: Linear ramp between Edge A and Edge B.
- SMOOTH STEP: Cubic curve ($t^2(3-2t)$). Standard soft transition.
- SMOOTHER STEP: Quintic curve ($t^3(6t^2-15t+10)$). Even softer.
- SMOOTH MIN: Softly blends to the smaller value (Union).
- SMOOTH MAX: Softly blends to the larger value (Intersection).
- PULSE: Returns 1.0 within a specific range, 0.0 outside.
- PULSE TRAIN: Repeating pattern of pulses.
Parameters
Blend Modes: The first value to blend.
Blend Modes: The second value to blend.
Blend Modes: The "k" factor (smoothness amount). Higher values create a wider, softer blend area between Input 1 and Input 2.
Quick Recipes
Practical shaping scenarios.
Perfect Soft Mask
- Mode SMOOTH STEP
- Input 1 0.3
- Input 2 0.7
- Mixer Gradient
Isoline (Band)
- Mode PULSE
- Input 1 Center (0.5)
- Input 2 Width (0.1)
- Mixer Noise
Liquid Merge
- Mode SMOOTH MIN
- Input 1 Shape A
- Input 2 Shape B
- Mixer 0.2