docs: updated contribuition guide

CONTRIBUTING.md

@@ -1,4 +1,4 @@
-![repository-banner.png](/public/repo-banner.png)
+![repository-banner.png](https://res.cloudinary.com/alvarosaburido/image/upload/v1683452574/repo-banner_d2xeem.png)
 
 # Tres Contributing Guide
 
@@ -8,9 +8,25 @@ No contribution is too small, whether it is a typo in the docs, a bug report or
 
 Thanks from the heart 💚 for taking the time to help out. This guide will help you to get started with the project.
 
+## Ecosystem
+- [@tresjs/core](https://github.com/Tresjs/tres) - The core package.
+- [@tresjs/cientos](https://github.com/Tresjs/cientos) - The abstractions package.
+- [@tresjs/postprocessing](https://github.com/Tresjs/post-processing) - The post-processing package.
+
 ## Setup
 
-Tresjs is a monorepo using [pnpm workspaces](https://pnpm.io/workspaces). Pnpm is a package manager that is faster than npm and yarn, and it also uses symlinks to avoid code duplication.
+All the packages in the ecosystem uses [pnpm workspaces](https://pnpm.io/workspaces). Pnpm is a package manager that is faster than npm and yarn, and it also uses symlinks to avoid code duplication.
+
+
+The `workspace` have the following structure:
+
+```
+.
+├── docs // The documentation
+├── playground // The playground to test the package
+├── src // The source code
+
+```
 
 Make sure you are using [Node.js](https://nodejs.org/en/) version 14 or higher.
 
@@ -28,21 +44,22 @@ If you have the package manager installed, you can install pnpm using the follow
 brew install pnpm
 ```
 
-To develop Tres core or any of the packages, run `pnpm install` in the root of the project. This will install all the dependencies and link the packages together. There is also a `postinstall` script that will build all the packages.
 
 ## Development
 
-TresJS is an ecosystem of packages, each one of them has its own purpose. The main package is `@tresjs/core` which is the core of the library. The other packages are plugins that extend the core functionality, like `@tresjs/cientos` which is a plugin that adds a bunch abstractions and composables to make it easier to create 3D scenes.
+To start developing, you can run `pnpm run playground` in the root folder.
+
+This will start the dev server for the playground `http://localhost:5174/` where you can test the changes you are making on the `src` folder. 
 
-### Core
+> **Important**
+> There is no need to run anything in the `src` folder or in the root, the `playground` will take care of it
 
-You can go to the `packages/tres` folder and run `pnpm dev` to start the dev server. This will start a vite server that will watch for changes in the code and rebuild the package.
 
-This is only a playground to test the core package, to keep the `App.vue` clean create a new component with your scene and import it in the `App.vue` file.
+Whenever you are working on a new feature or fixing a bug, make sure to add a demo under `playground/src/pages` and create a route in the `playground/src/router.ts` to test the changes you are making.
 
-### Cientos
+> **Warning**
+> Make sure to check if there is already a demo for the feature you are working on, if there is, you can add your changes to the existing demo.
 
-You can go to the `packages/cientos` folder and run `pnpm build --watch` to build the package and watch for changes. That way you can test the changes in the playground on the `packages/tres` folder.
 
 ### Docs
 
@@ -72,6 +89,10 @@ Before opening a pull request, make sure to run `pnpm lint` to make sure the cod
   - Create a `fix/{issue-number}-fix-test-in-core` branch for this bug fix.
   - If you are resolving a special issue, add `(fix #xxx[,#xxx])` (#xxx is the issue id) in your PR title for a better release log, e.g. `update entities encoding/decoding (fix #3899)`.
 
+## Third Party Libraries
+
+Adding a new third party library is generally discouraged, unless it is absolutely necessary. If you want to add a new library, please open an issue first to discuss the best approach.
+
 ## Keep core small
 
-The core package should be as small as possible, it should only contain the core functionality of the library. If you are adding a new feature, please consider adding it as a plugin instead, for example, if you want to add support for [Effect Composer](https://threejs.org/examples/?q=compo#webgl_postprocessing_effectcomposer) you should create a new package called `@tresjs/postprocessing` and add it as a plugin. If it's a smaller scope you can always add it to `cientos` package.
+The core package should be as small as possible, it should only contain the core functionality of the library. If you are adding a new feature, please consider adding it as a plugin instead, for example, if you want to add support for [Effect Composer](https://threejs.org/examples/?q=compo#webgl_postprocessing_effectcomposer) you should create a new package called `@tresjs/post-processing` and add it as a plugin. If it's a smaller scope you can always add it to `cientos` package.