Switchable LeiaSR Lenses

LeiaSR consumer devices will be outfitted with lenses whose nature can be changed such that two dimensional experiences can benefit from the full resolution of the physical display. When LeiaSR applications are performing weaving of images that are rendered specifically for the left and right eye of the user, the lens can be switched to LeiaSR mode. This mode wil present a three dimensional experience to the user.

To do this, LeiaSR applications should declare a SR::SwitchableLensHint. By calling SR::SwitchableLensHint::enable when weaved images are displayed or SR::SwitchableLensHint::disable when a two dimensional user interface is presented, developers can indicate their preference for the lens state.

Window Minimization and Focus

If no SR::SwitchableLensHint is defined, the assumption will be made that the lens effect should be enabled during the lifetime of the application. Since an end-user might be using multiple applications at the same time it is considered good practice to implement provisions for dealing with minimization and shifting focus between applications.

The most straightforward way of implementing this behavior under Windows is to handle events that indicate whether the window has focus. (for example the WM_KILLFOCUS and WM_SETFOCUS events.) Most UI frameworks have their own way of providing this information in an event based manner. Below is a small example of how this could work.

class MyWindow {
    SR::SRContext context;
    SR::SwitchableLensHint* lens;
public:
    Mywindow();
    OnKillFocus();
    OnSetFocus();
}
 
MyWindow::Mywindow() {
    lens = SR::SwitchableLensHint::create(context);
}
 
void MyWindow::OnKillFocus() {
    lens->disable();
}
 
void MyWindow::OnSetFocus(){
    lens->enable();
}

note: In some software, it might be desirable to allow the user to opt-out of this behavior if they are using multiple displays and want to simultaneously view the application on the LeiaSR display and have focus on some other application which is running on a regular display.

Switchable LeiaSR Development Kits

The LeiaSR Development Kit currently can not switch between viewing modes in the same way. That means that SR::SwitchableLensHint does convey intent on the LeiaSR Development Kit but does not have an effect on the lens. However, the native 8K resolution of the display is so high that it can still be used for displaying two dimensional elements when it's provided with images in 4K resolution. (3840 x 2160)

The resolution of the display can be switched between two modes, by switching the device will expect a different type of input.

3840 x 2160 (two dimensional images expected by the LeiaSR device, leading to a two dimensional experience)
7680 x 2160 (stereo side-by-side LeiaSR expected by the LeiaSR device, leading to a three dimensional experience)

Both these inputs are converted in hardware to 7680 x 4320 to be displayed on the actual LCD