Chart: A JVM Tile Map Library for Compose Desktop

Overview

Chart is a JVM library designed for loading and displaying map tiles using Compose Desktop. It's structured to be both modular and adaptable, catering to a range of use-cases. Whether you're building a standard map application or something more specialized, Chart has got you covered.

Declaring Dependencies

To integrate Chart into your project, include the necessary dependencies:

val chartVersion = // Recent version
        
// Composable (required)
implementation("com.mmoczkowski:chart-ui:$chartVersion")

// Cache API (required)
implementation("com.mmoczkowski:chart-cache-api:$chartVersion")

// Cache implementations (you need at least one)
implementation("com.mmoczkowski:chart-cache-impl-lru:$chartVersion")
implementation("com.mmoczkowski:chart-cache-impl-no-op:$chartVersion")

// Tile Provider API (required)
implementation("com.mmoczkowski:chart-provider-api:$chartVersion")

// Tile Provider implementations (you need at least one)
implementation("com.mmoczkowski:chart-provider-impl-google:$chartVersion")
implementation("com.mmoczkowski:chart-provider-impl-open-street-map:$chartVersion")
implementation("com.mmoczkowski:chart-provider-impl-url:$chartVersion")

Usage

Using Chart is intuitive and straightforward. Here's a simple guide to help you get started:

1. Initialize a Cache: Start by defining the type of cache you want to use. For instance, to use an LRU cache:

   val lruCache = rememberLruCache<TileCoords, ImageBitmap>(maxSize = 150)
   

2. Select a Tile Provider: Depending on your requirements, choose the tile provider. For using OpenStreetMap:

   val tileProvider = rememberOpenStreetMapTileProvider()
   

3. Render the Map: Now, simply display the map using the Chart composable. Here's a basic setup:

   Chart(
       provider = tileProvider,
       cache = lruCache,
   )
   

This code sets up a basic map using the OpenStreetMap tile provider and an LRU cache. You can customize this further by opting for different tile providers, creating custom success/error/loading composables, or even incorporating markers.

Project Structure

• :build-logic: - Build configuration and convention plugins.
• :cache:api - Cache API for map tile storage.
• :cache:impl:lru - In-memory Least Recently Used (LRU) caching implementation.
• :cache:impl:no-op - A mock or "no-operation" cache, useful for testing and development.
• :provider:api - The blueprint for the Tile Provider API.
• :provider:impl:debug - A debug variant of the tile provider for developmental purposes.
• :provider:impl:google - Google Map Tiles API tile provider implementation.
• :provider:impl:open-street-map - OpenStreetMap tile provider implementation.
• :provider:impl:url - A versatile, URL-driven tile provider adaptable to a variety of sources.
• :ui - The heart of the user interface, housing the Chart composables.