The Meg Sighting: Facebook AR Effect
By Kit Kong
Incorporating a full fledged 3D scene into augmented reality rather than just a 3D model presents many challenges. This is especially true when working with ‘out of the box’ AR tools with strict limitations on file sizes, file formats among other things.
In the case of AR Studio by Facebook, we are given a nice set of tools to create simple AR effects overlaid on the Facebook Camera. However, we are limited to a downloadable file size of 2MB, texture resolutions of no more than 1024 x 1024 pixels, audio files in Mono M4A, and more.
This poses a problem for large animated 3D scenes such as ours, which includes an animated 3D model, animated textures as well as real time dynamic lighting.
In our “The Meg Sighting” AR experience, we wanted to recreate a digital representation of a beach environment with the megalodon swimming through the waters. To give the user a sense of scale of just how large the megalodon is, we had to scale everything to real life sizes which means an environment of over 50 thousand square feet.
As a large majority of this space is occupied by the ocean, our biggest challenge was to create a convincingly large body of water. To maximize the fidelity of the water, we tried using the largest texture size available to create a short loopable sequence on the water plane. Not only did this easily push us over the 2MB file size threshold, but the quality of the texture was also highly pixelated as the texture is stretched over tens of thousands of feet.
From our research, most users won’t move very far from the starting location. Therefore, to increase quality without increasing overall texture size, we cheated a little by modifying the UV of the water plane mesh to cover larger portions of the texture where the user starts the experience such that the fidelity of the water will be higher near the starting point of the user and degrades as you get further away. This drastically improved the pixelation of the water near the user’s starting point while keeping file size and texture resolutions the same.
Follow the link below on your mobile device to try the experience for yourself.
