> For the complete documentation index, see [llms.txt](https://docs.flatredball.com/flatredball/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.flatredball.com/flatredball/api/flatredball/math/geometry/circle/collideagainstmove.md).

# CollideAgainstMove

### Introduction

The CollideAgainstMove method performs the following:

* Returns true if a collision has occurred.
* Repositions the calling Circle and/or the argument object depending on the argument masses.

**Note:** All collision methods, including CollideAgainstMove, are common to all Shapes. If you came here through a link on a page beside the Circle (such as Polygon), don't worry, the code for all shapes is identical.


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