Using a C# script export a GameObject as an FBX during runtime

Question

I'm trying to build a room editor. So users have placed furniture, rotated them etc. All the objects are saved as children of a Room parent. I need to program in functionality to now save the Room along with its children as an FBX or OBJ so it can be sent and be viewed via any 3D viewing software or even opening it up in something like blender (Textures aren't a concern yet)

I tried looking at using the Streamwriter but that doesnt seem to be capable of it. I've looked at https://docs.unity3d.com/ScriptReference/PrefabUtility.html but this doesnt export the prefabs but instead just stores them in project files.

Does anyone have any idea or suggestions of what i could use to go about this

Answer 1

The FBX SDK bindings can be executed during gameplay allowing import and export at runtime.

NOTE: The FBX SDK bindings are Editor only by default and will not be included in a build. In order for the package to be included in the build, add the FBXSDK_RUNTIME define to Edit > Project Settings... > Player > Other Settings > Scripting Define Symbols.

using UnityEngine;
using UnityEngine.UI;
using Autodesk.Fbx;
using System.IO;

public class WriteFBXonEvent : MonoBehaviour
{
    //Make sure to attach these Buttons in the Inspector
    public Button m_HitMeButton;

    void Start()
    {
        Button btn = m_HitMeButton.GetComponent<Button>();
        btn.onClick.AddListener(TaskOnClick);
    }

    void TaskOnClick()
    {
        // Build the fbx scene file path 
        // (player/player_data/emptySceneFromRuntime.fbx)
        string fbxFilePath = Application.dataPath;
        fbxFilePath = Path.Combine(fbxFilePath, "emptySceneFromRuntime.fbx");
        fbxFilePath = Path.GetFullPath(fbxFilePath);

        Debug.Log(string.Format("The file that will be written is {0}", fbxFilePath));

        using (var fbxManager = FbxManager.Create())
        {
            FbxIOSettings fbxIOSettings = FbxIOSettings.Create(fbxManager, Globals.IOSROOT);

            // Configure the IO settings.
            fbxManager.SetIOSettings(fbxIOSettings);

            // Create the exporter 
            var fbxExporter = FbxExporter.Create(fbxManager, "Exporter");

            // Initialize the exporter.
            int fileFormat = fbxManager.GetIOPluginRegistry().FindWriterIDByDescription("FBX ascii (*.fbx)");

            bool status = fbxExporter.Initialize(fbxFilePath, fileFormat, fbxIOSettings);
            // Check that initialization of the fbxExporter was successful
            if (!status)
            {
                Debug.LogError(string.Format("failed to initialize exporter, reason: {0}",
                                               fbxExporter.GetStatus().GetErrorString()));
                return;
            }

            // Create a scene
            var fbxScene = FbxScene.Create(fbxManager, "Scene");

            // create scene info
            FbxDocumentInfo fbxSceneInfo = FbxDocumentInfo.Create(fbxManager, "SceneInfo");

            // set some scene info values
            fbxSceneInfo.mTitle = "fromRuntime";
            fbxSceneInfo.mSubject = "Exported from a Unity runtime";
            fbxSceneInfo.mAuthor = "Unity Technologies";
            fbxSceneInfo.mRevision = "1.0";
            fbxSceneInfo.mKeywords = "export runtime";
            fbxSceneInfo.mComment = "This is to demonstrate the capability of exporting from a Unity runtime, using the FBX SDK C# bindings";

            fbxScene.SetSceneInfo(fbxSceneInfo);

            // Export the scene to the file.
            status = fbxExporter.Export(fbxScene);

            // cleanup
            fbxScene.Destroy();
            fbxExporter.Destroy();
        }
    }
}