CitraVR (Experimental) Lubos/DrBeef/fewerwrong Immersive Mode

This is an experimental extra release for the weekend.

It contains a new version of @lvonasek's 180 Immersive Mode, with initial implementation by @lvonasek, improved visual quality by @DrBeef, with some shader-cache separation by me, @amwatson (fewerwrong).

To Enable Immersive Mode

1. Download and install the attached apk
2. On your HMD, launch "CitraVR (EXPERIMENTAL)"
3. Go to Settings > VR and check "(Experimental): VR180 Immersive Mode"

Notes:

• Different games and different game stages will have visual different results. This is a natural consequence of the technique -- with it, some games/levels will look excellent.
• Extending the screen changes the depth value. You may want to increase your depth slider when Immersive Mode is enabled.
• Your shaders are going to need to be recached, so you'll see some initial stutters like the first time you ran. These will go away.
• I am upscaling a bit to make up for loss-of-quality, so immersive mode at X resolution may perform worse than non-immersive-mode at the same resolution.
• It will only run OpenGL (if you selected Vulkan, it overrides this setting)
• This apk will not override your main version of CitraVR. When you select "Unknown Sources" you will see "CitraVR" and "CitraVR (EXPERIMENTAL)" as separate items.
  • To avoid "CitraVR (EXPERIMENTAL)" introducing issues to CitraVR, I recommend either a) creating a new userdata directory for "CitraVR (EXPERIMENTAL)" or b) deleting your shaders (located at [path-to-userdata]/shaders/opengl) when you're done with experimental.

DPAD

I'd feel like a dick if I didn't have the dpad working for immersive. While It's not the most comfortable way to enter Dpad input, I intend to fix this in the future, and hopefully it's serviceable.
To use Dpad on touch: click the thumbstick in on either controller. While clicking, move the thumbstick to use DPAD_UP, DPAD_DOWN, DPAD_LEFT, DPAD_RIGHT.

Alternatively, on the command-line, use adb shell input keyevent KEYCODE_DPAD_UP