---
title: "Arccosine"
url: "https://help.maxon.net/c4d/en-us/Content/html/COM_REDSHIFT3D_REDSHIFT4C4D_NODES_CORE_RSMATHACOS.html"
section_path: "The Node Editor > Redshift Nodes > Redshift Math Nodes > Math Float Nodes > Arccosine"
element_id: "COM_REDSHIFT3D_REDSHIFT4C4D_NODES_CORE_RSMATHACOS"
description: "This page documents the Arccosine node of the Redshift renderer in Cinema 4D. It returns the arc-cosine of its input — typically converting dot-product …"
---

# Arccosine

> **Note:** **What is it about?**
>
> This page documents the **Arccosine node** of the Redshift renderer in **Cinema 4D**. It returns the arc-cosine of its input — typically converting dot-product results back into angles for angle-based shading logic.

Returns the arc-cosine of *Input*. When *Radians* is selected, the output range will be between 0 and PI, otherwise 0 and 180 degrees.