How Do Panoramas in Google Earth Look?
Here’s a preview of what the next Google Earth feature could potentially look like (I don’t know).
I’m impressed with how good a simple sphere of imagery looks just floating there above the earth. The warping effect has a sort of natural bubbleness. And as the POV flies in towards the center of the sphere, you can see the distortion effect I mentioned last time. It’s not as jarring as I expected, but it’s certainly noticeable. Fading these spheres in as you approach may improve things a bit. The thing to consider is what happens when there are a thousand of these in close proximity.
What this really needs, though, is better controls. The video seems to be using a 6DOF controller like the 3DConnexion one we blogged about last month. I did purchase one, btw, but I don’t use it as much as I’d like just yet. BTW, the initial settings are bad, so beware that you’ll need to adjust the various sensitivities before feeling really comfortable with it. The company would do well to add a training app that lets you steer a cube around with on-screen sliders to adjust the action until it feels just right. But at least Sketchup has a way to invert the sense of the controls to flying vs. moving the model. This device suffers from the “volume problem” I blogged about a while back — it has sensitivity adjustments that multiply with those of an application, making universal tuning difficult.
Anyway, what these panoramas really need, especially for mouse users, is a way to link the normal earth-navigating controls to the viewing of the spheres. Here’s one way: click on a sphere and auto-pilot the viewer inside the sphere. The center is the sweet spot for seeing minimal distortion (zero, if your eyes are a little “fishy”). But there’s no good way with a mouse to spin your view within the sphere, like pan and tilt, as you do in QuicktimeVR.
That leads to the second, better, approach. Currently, when you click on the earth, you’re grabbing the spot you click and the rotation (of the whole earth, or you around the earth) is computed by seeing where you drag that spot to, such that the earth stays locked to the mouse, like your finger on a globe. GE could do the same thing for these spheres, but treating the center of the sphere as your new temporary center of rotation.
So, for example, you see a sphere nearby and click within it. GE figures out you clicked the sphere, not the ground. It sees how much you move the mouse after you click, and it computes a new rotation around the image sphere itself, as if the sphere was a kind of handle you could spin yourself around (like the teacups at Disneyland) or a mini-earth that’s glued down. Zooming would now zoom you in and out of the center of the sphere, right up to the sweet spot, and back out again. When you grab the earth, or perhaps when you release the mouse button, you’re back to the normal controls. Simple and effective, but something GE would have to implement for now.
As always, I have no knowledge of Google’s plans or what’s currently going on inside the app. Just my educated guesses from past experience.
Afterthought: using a literal sphere textured with panoramas is the simple approach, but there’s another one that would work quite well. Almost all 3D video cards support cubic environment maps. It’s just like a panorama sphere except the shape is a cube and that makes it more efficient for the hardware. Transforming a sphere to a cube is not hard. But once in cube map form, you could use any shape geometry and get similar results. For example, you could make a big magnifying glass that shows the panorama as if seen through the glass. You could make a mirror ball that reflects the panorama instead of the flat map. And you could more easily warp the geometry as you fly closer, going from a billboard (plane) to a full cube or sphere as a function of distance. But again, it’s something GE would have to support internally.