Sinus

DF_Sinus is Derfuu_ComfyUI_ModdedNodes' sine node - the mirror image of DF_Cosines in the same pack, both living under Derfuu_Nodes/Math/Trigonometry. It's a small pack of math and utility nodes that's been floating around ComfyUI since 2023, mostly there to fill gaps ComfyUI's own widgets didn't cover back then: arithmetic, rounding, string handling, and yes, trig functions for anyone doing something curve-driven inside a graph.

Nobody needs this for a standard txt2img or img2img workflow. It's for the minority of setups where a value in the graph needs to follow a periodic curve rather than a straight line - think staggering a parameter across a batch on a sine wave instead of a linear ramp, or any homebrew math chain someone wired up node-by-node before ComfyUI had an expression evaluator.

Inputs and output

Three required inputs:

• value - the angle to take the sine of, or (with arcSin on) the ratio you want the angle for
• type_ - RAD or DEG, so the node works in whichever unit the rest of your math is using
• arcSin - toggles the node between sine and its inverse, arcsine

It returns one FLOAT. With arcSin off, that's sin(value), always between -1 and 1. Flip arcSin on and it goes the other way: feed it a ratio, get back the angle it corresponds to, in radians or degrees depending on type_. Having both directions in a single node with one toggle, rather than as two separate nodes, is a small but genuinely convenient design choice.

Why it exists in this pack specifically

Derfuu_ComfyUI_ModdedNodes reads like someone's personal math toolbox that got shared publicly - Sum, Subtract, Power, Square root, and the two trig nodes (Sinus and Cosines) cover the operations you'd need to build almost any formula, one node per operation. That's the tradeoff: nothing hidden, every step visible on the canvas, but a formula with five operations means five nodes wired together. The more modern answer to the same problem is rgthree's Power Puter, which evaluates a python-like expression in one node instead of a chain - genuinely less setup if you're starting fresh and just need sin(x) * 2 + offset computed once. DF_Sinus is worth reaching for if you're already deep in a Derfuu-built math chain and want consistency, or if you'd rather see every intermediate value as its own node for debugging.

Installing

Like every node in this pack, DF_Sinus comes bundled with the whole repo - there's no standalone install. Through ComfyUI Manager: search Derfuu_ComfyUI_ModdedNodes, install, restart ComfyUI. Manually:

cd ComfyUI/custom_nodes
git clone https://github.com/Derfuu/Derfuu_ComfyUI_ModdedNodes

then restart. It's plain Python math with no model downloads and no unusual dependencies, so the install itself is quick and rarely the source of problems.

Troubleshooting

If the node isn't visible in the menu right after installing, restart the server and then hard-refresh the browser - that's the standard fix for a node that shows as loaded in the console but isn't rendering in the frontend, and it applies to basically any custom-node pack, not just this one.

The pack-specific thing to watch for: Derfuu has, in the past, removed deprecated nodes outright between updates rather than keeping a legacy version around, and long-time users of the pack have flagged exactly that - nodes they relied on disappearing with no warning after an update. Trig nodes haven't been the ones affected historically, but if you update the pack and an old workflow suddenly throws a missing-node error on a node it used to load fine, that maintenance habit is the first thing to suspect - check the GitHub repo for a rename before assuming your setup is broken.