> 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/tiled-plugin/glue-gluevault-component-pages-tile-graphics-plugin-tileshapecollection/collideagainst.md).

# CollideAgainst

### Introduction

The CollideAgainst function returns a bool value indicating whether the calling TileShapeCollection collides with the argument. CollideAgainst can be used to test collisions against:

* ICollidable (usually Glue entities)
* AxisAlignedRectangle
* Circle
* Line
* Polygon

Note that in most cases CollideAgainst does not need to be called because collision relationships can be created between TileShapeCollections and Glue ICollidable entities.

### Code Example

The following code shows how to test if an entity is colliding with a TileShapeCollection whenever the space bar is pressed. The code assumes that the entity implements ICollidable.

```lang:c#
var keyboard = InputManager.Keyboard;

if(keyboard.KeyPushed(Keys.Space))
{
   // Assuming GroundCollision is a valid TileShapeCollection and
   // CollidableEntityInstance is a valid entity instance
   var collides = GroundCollision.CollideAgainst(CollidableEntityInstance);
   
   // collides can be used here
}
```


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation by asking a question.

Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters:

```
GET https://docs.flatredball.com/flatredball/tiled-plugin/glue-gluevault-component-pages-tile-graphics-plugin-tileshapecollection/collideagainst.md?ask=<question>&goal=<user_goal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.