if I understood you correctly: You're trying to display an UI over a big surface (let's say a desk/table) and map it to the surface's bounds?
My first idea would be to place a single marker in the center of the surface and then use extended tracking as well. However, if your surface consists of a plain, uniform colored plane it's hard for the extended tracking to determine a concrete position without having the target in sight. A potential fix could be to either place objects on your surface or use some kind of tablecloth to add more texture to your surface so the extended tracking can find more indicators to track the environment. If you say the extended tracking didn't work well for you, what exactly do you mean by that?
A second idea would be to place a single, bigger marker or even cover your whole surface with it so it is recognized more easily. Unfortunately if you're intending to zoom in on your surface this idea doesn't work well since the marker won't be recognized any more once you're moving too near to it.
A third option would be to use plane detection. You could scan your surrounding until the whole surface you want to use got recognized. You could then tap on the desired surface to display your UI on it and disable rendering the detected surfaces. Just make sure to stop checking for new planes once you've selected the one you'd like to use.
That being said, I'm a bit worried when you say you're facing stability problems and your tracker scanning is delayed. Does the same happen when using our samples?
If you're using our Unity Expert Edition SDK, there's a sample called "Multiple - Image Tracking". Using this image you can test five objects at once.
If you're using our Unity Professional Edition SDK, there's a sample called "Image Tracking - Multiple Targets". Using this and this image you can test multiple objects when putting the images aside (like opening multiple browser windows and arranging them on your screen accordingly)
Note: The samples were temporary disabled in the current 9.12 version of our SDK. But they're available in the 9.10 version you can find here.
If you're not facing stability problems testing them, maybe there's something in your code that causes them.
I hope that I could help you with your issue.
With best regards,
Vinicius Camargo Rocha de Souza
Hi, I'm using Unity SDK 9.12 and I want to make a UI panel that uses 4 image tracking to anchor, it's a big panel so the 4 trackers. At first, I tried using extended tracking to fix the panel, however I had problems and it didn't work well. Then came the idea of the 4 differents qr codes, but despite working better, I still have stability problems and delay to scan the tracker. The build is being made for the VuziX M400. What do you guys recommend to make this? Help.