All content in this course uses:

Working with the StreamingAssets Folder - 2019.2

In this tutorial, you’ll learn how to use the 

 folder to allow users to load their own images, songs, and even game levels into a project.

This tutorial has been verified using Unity 2019.4.14f1 LTS - 

https://learn.unity.com/tutorial/working-with-the-streaming-assets-folder-2019-3

 folder to allow users to load their own images, songs, and even game levels into a project. 

Working with the StreamingAssets Folder

 folder is the same as for loading a web-based resource, as we’ll see in the following exercise. 

Loading Assets Stored in the StreamingAssets Folder

For this first exercise, we’ll use a button loaded from 

1. Inside the Assets folder, create two new folders and name them: 

 folder, place an image file, making note of the file name.  This will be the image first loaded during runtime. (Example: ‘

, place another image file, again making note of the file name. (Example: ‘

4. From the GameObject drop-down menu, select 

. You can assign the first image to load ‘

to the ImageDisplay by selecting the circle button, next to the Texture field in the Inspector window (

Note that any images in your project are visible for selection, 

for any saved images inside the StreamingAssets folder.  Images saved to the StreamingAssets folder remain hidden.

5. From the GameObject drop-down menu, select 

.  We will use a script in an upcoming step to set the second image to ‘

6. With the ImageDisplay object selected in the Hierarchy Window, Create a new C# script by selecting the button: 

7. Double-click the script to open in your script editor.

9. We use a helper function to return the path to the file we want to load because the 

 folder location varies by platform. We’ll use this in all of our examples. Inside the class definition, beginning on line 9, type In the following code, replacing “Image2.png” with the name of your image file saved to the StreamingAssets folder. 

 subfolder. Let’s say your image file is named “logo.png” and is in a subfolder called “LogoImages.” In this case, you’d specify “LogoImages\\logo.png” for customTextureFilename if referencing this file in the script. We will use the double-slash \\ to reference the folder location and image name. (A single slash \ is used as an escape sequence for including special characters in the code, and wouldn’t work in this case) You don’t need to use \\ if you’re just typing the file name in the Unity Inspector.  In that case, you’d just enter 

11. Save changes and return to the Unity Editor.

12. With the ImageDisplay button selected in the Hierarchy window, select the Inspector window, and on the Button properties, select 

to add an action to its OnClick event listener (

13. Drag ImageDisplay into the slot labeled None (Object).

14. Select the drop-down currently labeled No Function and select 

15. Enter Play Mode. When you select the UI Button, the Raw Image changes from ‘Image1.png’ from the Images folder to ‘Image2.png’ loaded from the StreamingAssets folder.

Loading Images for Display

For our next example, we’ll load a song from the 

 folder at the start of the Scene, set it to loop, and start it playing. This could serve as the basis for allowing a user to load their own background music in a game editor.

 and place your song in there. The song needs to be in a Unity-supported format.

 from the GameObject drop-down and name it 

3. Attach a new C# script to BGMPlayer called 

7. Now we’ll load our song. If the GameObject to which this script is attached already has an AudioClip, we need to clear that out. If there’s no AudioSource, a new one will be created. Volume and looping settings are applied to the Audio Source, and the song is loaded and assigned. Once ready to play, the song starts and the Coroutine exits.

After the code from Step 6, type 

9. Enter Play Mode. Your song should load and begin playing.

Custom Soundtracks

For our final example, we’ll revisit loading a Texture from 

. This time, we’ll use it as the legend for building a level, with each pixel representing a cell in the Unity world, and each unique color representing some Prefab. This exercise can be done in the same Scene as our previous example to load not just custom music, but also a custom level for it to accompany. 

2. Outside of Unity, create a 64x64 bitmap. Fill it with white and, using the hard pixel brush/pencil tool, draw some assortment of dots, lines, and shapes in two or three  colors, making note of each color. Be sure that you’re not using anti-aliasing, but rather hard pixels (

4. If you don’t already have a subfolder named 

5. From the GameObject drop-down, select 

6. Repeat this with as many colored shapes as you used in your image, or create whatever Prefab you like. Ideally, your Prefabs should be exactly 1 Unity unit in each dimension. The reason why will become clear once we load our level.

10. Before we define our class, we’ll create a data structure for our level editor. This structure will hold a color and an assigned Prefab. We’ll make it Serializable so that we can edit it in the Inspector. Outside the class definition, type:

11. We’ll now declare our custom level file name, our list of possible level pieces, and our helper function to find our files in 

 before defining our method to actually load the level in the next step. Inside the class definition, type: 

 and iterates through each pixel. If the pixel’s color matches that of any of the defined level pieces, that piece is instantiated in the matching location of the game world.

Type: 

13. We’ll invoke LoadLevel as soon as the Scene starts. In 

. Select the triangle next to Pieces in its Inspector. Set 

 to the number of colors you used (aside from the background color).

16. For each piece, assign the color you used to represent it in the bitmap, making sure to set alpha to 

. This is necessary because Unity considers the alpha value as well as rgb when looking for a match.

17. After each color, assign the matching Prefab (

18. Enter Play Mode. The level should load instantly (

19. Exit Play Mode. This script can be used for 2D as well, by replacing Prefabs with Sprites and instantiating a 1x1 unit (not pixel) Sprite Prefab at each cell location.
 

Custom Game Levels

 folder is an easy way to allow users to save, load, and work with their own files in your Unity Project. 

Unity Version 2019.4