Dynamic 2D Grass

A stylised 2D pixel-art grass system for Godot 4.5+, featuring wind animation, character-reactive displacement, grass destruction via effector decals, and world-space cloud shadows.

Created by Jomoho Games, based on original work by Dylearn.

Features

• Camera-adaptive grass streaming (handles large tilemaps efficiently)
• Per-instance wind sway via dual scrolling noise textures
• Stepped framerate animation with per-blade phase offset
• Fake perspective UV squishing
• Noise-based colour patches and accent grass variants
• Character-reactive displacement via effector system
• Grass destruction and regrowth via effector decals
• Full-scene cloud shadow overlay with pseudo-3D offset
• TileMapLayer integration with automatic grass placement
• All parameters exposed as @export properties in the inspector

Installation

From the Godot Asset Library

1. Open your project in Godot 4.5+
2. Go to AssetLib tab
3. Search for Dynamic 2D Grass
4. Click Download and Install
5. Enable the plugin: Project > Project Settings > Plugins > Dynamic 2D Grass

Manual Installation

1. Download or clone this repository
2. Copy the addons/dynamic_2d_grass/ folder into your project's addons/ directory
3. Enable the plugin: Project > Project Settings > Plugins > Dynamic 2D Grass

Quick Start

1. Set up your TileMapLayer

Create a TileMapLayer node with your ground tiles. The grass system reads this to decide where grass grows.

Add a custom data layer to mark grass tiles:

1. Select your TileSet resource
2. Go to Custom Data Layers in the TileSet inspector
3. Add a layer named is_grass with type bool
4. Open the TileSet editor, select tiles that should have grass
5. In each tile's Custom Data panel, set is_grass = true

Only tiles marked with is_grass = true will generate grass blades.

Add a navigation polygon layer (optional):

For per-tile grass coverage shapes (e.g. sloped edges, partial coverage), you can use navigation polygons to define the exact grass boundary:

1. Add a Navigation Layer to your TileSet
2. Draw navigation polygons on individual tiles in the TileSet editor — these define the area where grass can grow within that tile
3. Set the grass_nav_layer export on both GrassChunkManager2D and GrassEffectManager2D to match the navigation layer index you used

If no navigation polygon is set on a tile, the full tile area is used.

2. Add GrassChunkManager2D

Add a GrassChunkManager2D node (from addons/dynamic_2d_grass/scripts/GrassChunkManager2D.gd) to your scene and configure:

3. Add GrassEffectManager2D

Add a GrassEffectManager2D node and configure:

4. Add effectors

To make objects interact with grass, add GrassEffector2D as a child of any Node2D:

• Set a texture for the effect shape
• Choose target_channel: R (displacement), G (coverage), B (cloud Y-offset), A (cloud immunity)
• Choose blend_operation: ADD (accumulate) or SUB (erase)

5. Add cloud shadows (optional)

Add a CanvasLayer with a ColorRect child. Attach CloudOverlay2D.gd to the ColorRect and assign:

• The included cloud_overlay_material.tres as the material
• References to your camera and effect manager

6. Add a CRT post-process shader (recommended)

The pixel-art grass looks best with a CRT or retro post-processing shader on top. The example project includes the Flowerwall CRT shader for this purpose. Any CRT/scanline shader will work — it helps blend the pixel-art aesthetic and hides sub-pixel seams.

Example Scene

An example scene is included in example/scenes/Demo2D.tscn. Open it to see the full system in action with a tilemap, grass, effectors, bombs, and cloud shadows.

The example/ directory is optional and can be safely deleted without affecting the addon.

Addon Structure

addons/dynamic_2d_grass/
  scripts/      GDScript components
  shaders/      Grass, cloud, effector, and mask shaders
  materials/    Pre-configured ShaderMaterials
  textures/     Default grass sprite atlas
  noise/        Noise resources for wind, clouds, and colour patches

License

This project uses two licences:

• Code (scripts, shaders): MIT License -- Jomoho Games, based on original work by Dylearn
• Art assets (textures, visual content): CC BY 4.0

Third-Party Assets

• Grass art: Dylearn
• Tree sprites: GraphScriptDev
• Character sprites: Zerie