Displaying thumbnails in a grid

A thumbnail is a mini version of the full image. Therefore, we don't need to load a full-sized texture bitmap. For the sake of simplicity, let's just always sample it down by 4 (to 1/16th the original size).

The thumbnail image

In the Image class, the show method loads the full texture. Let's write a similar showThumbnail method that uses a smaller sampling. In the Image class, add the following code:

    public void showThumbnail(CardboardView cardboardView, Plane thumb) {
        loadTexture(cardboardView, 4);
        BorderMaterial material = (BorderMaterial) thumb.getMaterial();
        material.setTexture(textureHandle);
        calcRotation(thumb);
        calcScale(thumb);
    }

The Thumbnail class

Create a new Thumbnail class for the project that will contain a small Plane object and an Image object to show on it. It also gets the current cardboardView instance, which Image will require:

public class Thumbnail {
    final static String TAG = "Thumbnail"...