Packing and blending textures

Textures are useful to store not only loads of data, not just pixel colors as we generally tend to think of them, but also for multiple sets of pixels in both the x and y directions and RGBA channels. We can actually pack multiple images into one single RGBA texture and use each of the R, G, B, and A components as individual textures themselves by extracting each of these components in the shader code.

The result of packing individual grayscale images into a single RGBA texture can be seen in the following image:

Why is this helpful? Well, in terms of the amount of actual memory that your application takes up, textures are a large portion of your application's size. So, to begin reducing the size of your application, we can look at all of the images that we are using in our shader and see if we can merge these textures into a single texture.

Any texture that is grayscale can be packed into one of the RGBA channels of another texture. This might sound a bit odd...