---
description: What the renderer class is and what it does.
title: Renderer
image: images/blockly_banner.png
---

# Renderer

The [`Renderer`][Renderer] is a factory class that bundles all of the other
components of a renderer together.

It contains methods for creating the [constant provider][constants],
[render info][render-info], [path object][path-object], and [drawer][drawer].
And it contains code for wiring them all together when it renders a block.

If you want to change just one part of an existing renderer (e.g. the constants)
you can subclass the relevant factory method.

[Renderer]: /reference/blockly.blockrendering.renderer
[constants]: /guides/create-custom-blocks/renderers/concepts/constants
[render-info]: /guides/create-custom-blocks/renderers/concepts/info
[path-object]: /guides/create-custom-blocks/renderers/concepts/path-object
[drawer]: /guides/create-custom-blocks/renderers/concepts/drawer
