Usage Examples

Basic Example

This example assumes that your are already familiar with the basic usage of BuildPipeline.BuildAssetBundles and want to switch to using Scriptable Build Pipeline with as little effort as possible.

The following code example shows how AssetBundles are currently built:

using System.IO;
using UnityEditor;

public static class BuildAssetBundlesExample
{
    public static bool BuildAssetBundles(string outputPath, bool forceRebuild, bool useChunkBasedCompression, BuildTarget buildTarget)
    {
        var options = BuildAssetBundleOptions.None;
        if (useChunkBasedCompression)
            options |= BuildAssetBundleOptions.ChunkBasedCompression;

        if (forceRebuild)
            options |= BuildAssetBundleOptions.ForceRebuildAssetBundle;

        Directory.CreateDirectory(outputPath);
        var manifest = BuildPipeline.BuildAssetBundles(outputPath, options, buildTarget);
        return manifest != null;
    }
}

To update the previous code example to use SBP instead, add a new using UnityEditor.Build.Pipeline and replace the call to BuildPipeline.BuildAssetBundles with CompatibilityBuildPipeline.BuildAssetBundles as shown below:

using System.IO;
using UnityEditor;
// Added new using
using UnityEditor.Build.Pipeline;

public static class BuildAssetBundlesExample
{
    public static bool BuildAssetBundles(string outputPath, bool forceRebuild, bool useChunkBasedCompression, BuildTarget buildTarget)
    {
        var options = BuildAssetBundleOptions.None;
        if (useChunkBasedCompression)
            options |= BuildAssetBundleOptions.ChunkBasedCompression;

        if (forceRebuild)
            options |= BuildAssetBundleOptions.ForceRebuildAssetBundle;

        Directory.CreateDirectory(outputPath);
        // Replaced BuildPipeline.BuildAssetBundles with CompatibilityBuildPipeline.BuildAssetBundles here
        var manifest = CompatibilityBuildPipeline.BuildAssetBundles(outputPath, options, buildTarget);
        return manifest != null;
    }
}

Notes: Some changes in the SBP building and loading process do not match the BuildPipeline behavior. For more information on these changes, see Upgrade Guide.

Per-Bundle Compression Example

The following example shows how to build your AssetBundles using different compression levels for each AssetBundle.This is useful if you are planning on shipping part of your bundles as Lz4 or Uncompressed with Player and want to download the remainder as Lzma later.

The simplest implementation is to create a custom build parameters class that inherits from BundleBuildParameters and override the GetCompressionForIdentifier method. Then construct and pass this into the ContentPipeline.BuildAssetBundles method.

using UnityEditor;
using UnityEditor.Build.Content;
using UnityEditor.Build.Pipeline;
using UnityEditor.Build.Pipeline.Interfaces;

public static class BuildAssetBundlesExample
{
    // New parameters class inheriting from BundleBuildParameters
    class CustomBuildParameters : BundleBuildParameters
    {
        public Dictionary<string, BuildCompression> PerBundleCompression { get; set; }

        public CustomBuildParameters(BuildTarget target, BuildTargetGroup group, string outputFolder) : base(target, group, outputFolder)
        {
            PerBundleCompression = new Dictionary<string, BuildCompression>();
        }

        // Override the GetCompressionForIdentifier method with new logic
        public override BuildCompression GetCompressionForIdentifier(string identifier)
        {
            BuildCompression value;
            if (PerBundleCompression.TryGetValue(identifier, out value))
                return value;
            return BundleCompression;
        }
    }

    public static bool BuildAssetBundles(string outputPath, bool useChunkBasedCompression, BuildTarget buildTarget, BuildTargetGroup buildGroup)
    {
        var buildContent = new BundleBuildContent(ContentBuildInterface.GenerateAssetBundleBuilds());
        // Construct the new parameters class
        var buildParams = new CustomBuildParameters(buildTarget, buildGroup, outputPath);
        // Populate the bundle specific compression data
        buildParams.PerBundleCompression.Add("Bundle1", BuildCompression.DefaultUncompressed);
        buildParams.PerBundleCompression.Add("Bundle2", BuildCompression.DefaultLZMA);

        if (m_Settings.compressionType == CompressionType.None)
            buildParams.BundleCompression = BuildCompression.DefaultUncompressed;
        else if (m_Settings.compressionType == CompressionType.Lzma)
            buildParams.BundleCompression = BuildCompression.DefaultLZMA;
        else if (m_Settings.compressionType == CompressionType.Lz4 || m_Settings.compressionType == CompressionType.Lz4HC)
            buildParams.BundleCompression = BuildCompression.DefaultLZ4;

        IBundleBuildResults results;
        ReturnCode exitCode = ContentPipeline.BuildAssetBundles(buildParams, buildContent, out results);
        return exitCode == ReturnCode.Success;
    }
}

Load By File Name Example

The following example shows how to use the CompatibilityBuildPipeline methods to load by a filename instead of the full path.

The example uses the ContentBuildInterface.GenerateAssetBundleBuilds() method to get the set of bundles and assets to build, then modifies addressableNames field to set the loading path of the filename instead of the full path.

using System.Linq;
using UnityEditor;
using UnityEditor.Build.Content;
using UnityEditor.Build.Pipeline;

public static class BuildAssetBundlesExample
{
    public static bool BuildAssetBundles(string outputPath, bool forceRebuild, bool useChunkBasedCompression, BuildTarget buildTarget)
    {
        var options = BuildAssetBundleOptions.None;
        if (useChunkBasedCompression)
            options |= BuildAssetBundleOptions.ChunkBasedCompression;

        if (forceRebuild)
            options |= BuildAssetBundleOptions.ForceRebuildAssetBundle;

        // Get the set of bundle to build
        var bundles = ContentBuildInterface.GenerateAssetBundleBuilds();
        // Update the addressableNames to load by the file name without extension
        for (var i = 0; i < bundles.Length; i++)
            bundles[i].addressableNames = bundles[i].assetNames.Select(Path.GetFileNameWithoutExtension).ToArray();

        var manifest = CompatibilityBuildPipeline.BuildAssetBundles(m_Settings.outputPath, bundles, options, m_Settings.buildTarget);
        return manifest != null;
    }
}

Building Archives that Contain ContentFiles

The following example shows how to build Archive files that contain ContentFiles by using the DefaultBuildTasks.ContentFileCompatible as the tasks for building

Using ContentFileIdentifiers is required, otherwise the resulting AssetBundles will not be able to load.

Requires Unity 2022.2 or later.

using UnityEditor;
using UnityEditor.Build.Content;
using UnityEditor.Build.Pipeline;
using UnityEditor.Build.Pipeline.Tasks;
using UnityEditor.Build.Pipeline.Utilities;

public class BuildAssetBundlesExample
{
    public static bool BuildAssetBundles(string outputPath, bool useChunkBasedCompression, BuildTarget buildTarget, BuildTargetGroup buildGroup)
    {
        var buildContent = new BundleBuildContent(ContentBuildInterface.GenerateAssetBundleBuilds());
        var buildParams = new BundleBuildParameters(buildTarget, buildGroup, outputPath);
        if (useChunkBasedCompression)
            buildParams.BundleCompression = UnityEngine.BuildCompression.LZ4;

        var tasks = DefaultBuildTasks.ContentFileCompatible();
        var buildLayout = new ClusterOutput();
        var exitCode = ContentPipeline.BuildAssetBundles(buildParams, buildContent, out _, tasks, new ContentFileIdentifiers(), buildLayout);
        return exitCode == ReturnCode.Success;
    }
}