Gaming Has it been documented how Mario Galaxy makes the pointer mechanic work?

[cal64]

I always thought it was done via raycasting, but seeing how the CPU's ability to read/write to the EFB is essential to making this feature work made me reconsider.
I couldn't find much details online. Any help?

 

[GreyWolf]

Do you mean how does the remote track the pointer in general? I don't think SMG uses any tricks. It's all in the controller library.

The remote has an infrared camera in it that picks up the flashes from the IR emitters on the sensor bar and triangulates the position and distance from the orientation and size of the light flashes.

 

[sarkwalvein]

I think he means mapping the 2D position read from the WiiMote (that is x, y in the screen) to the 3D position inside the 3D world (that is x, y, z, with the projected ray hitting a specific 3D world polygon).

 

[GreyWolf]

That would involve assigning a depth value to the targeting reticle and drawing an imaginary line from the center of the view through it. The first node in the scene graph that line hits is the target.

 

[cal64]

Oh my! Thanks for all the answers!
This was my first guess too, but such a system wouldn't require CPU access to the EFB, would it?
My second guess was then color picking, but does anyone know for sure?