How to change FOV / zoom in STEREO monitor mode?

Hey guys,

I was recently given one of those headsets that let you use your cell phone as VR device. I've then tried it with DCS in stereo monitor mode, but FOV is way too wide, making things very small (it looks like I'm sitting inside an origami cockpit). How do I change the FOV or zoom, when in stereo mode? All the commands for zoom don't seem work in this mode, not even the "toggle VR zoom"...

Thanks!

Ok, just figured it:

In this file:

\DCS World\Config\MonitorSetup\Stereo.lua

You will find the "projection_bounds" (left, right, top and bottom) values for each viewport (each eye). I just decreased each of these values to about half and it made the FOV in stereo mode significantly smaller (and the cockpit and the world significantly bigger). Problem solved, now I just have to adjust the numbers till I find the sweet spot.

The original numbers were, for the left viewport:

left = 0.964925826,

right = 0.715263844,

top = 0.889498115,

bottom = 1.11092532,

These values seem to be the tangents of the angles for the actual edges of the left eye's FOV. If that's true, arctangent will give the actual angles:

left = 44.0º,

right = 35.6º,

top = 41.7º,

bottom = 48.0º,

Which means that the left viewport has a horizontal FOV of 79.6º and a vertical FOV of 89.7º. If you, like me, reduce the original numbers to half:

left = 0.48,

right = 0.35,

top = 0.44,

bottom = 0.55,

You'll end up with:

left = 25.6º,

right = 19.3º

top = 23.7º

bottom = 28.8º

Which means your new horizontal FOV is 44.9º and new vertical FOV is 52.5º. The new FOV angles aren't half the original angles, because you're working with the tangents of the angles, not with the angles themselves.

Ok, just figured it:

 

In this file:

 

\DCS World\Config\MonitorSetup\Stereo.lua

 

You will find the "projection_bounds" (left, right, top and bottom) values for each viewport (each eye). I just decreased each of these values to about half and it made the FOV in stereo mode significantly smaller (and the cockpit and the world significantly bigger). Problem solved, now I just have to adjust the numbers till I find the sweet spot.

 

The original numbers were, for the left viewport:

 

left = 0.964925826,

right = 0.715263844,

top = 0.889498115,

bottom = 1.11092532,

 

These values seem to be the tangents of the angles for the actual edges of the left eye's FOV. If that's true, arctangent will give the actual angles:

 

left = 44.0º,

right = 35.6º,

top = 41.7º,

bottom = 48.0º,

 

Which means that the left viewport has a horizontal FOV of 79.6º and a vertical FOV of 89.7º. If you, like me, reduce the original numbers to half:

 

left = 0.48,

right = 0.35,

top = 0.44,

bottom = 0.55,

 

You'll end up with:

 

left = 25.6º,

right = 19.3º

top = 23.7º

bottom = 28.8º

 

Which means your new horizontal FOV is 44.9º and new vertical FOV is 52.5º. The new FOV angles aren't half the original angles, because you're working with the tangents of the angles, not with the angles themselves.

Thkx man.. gona try this today...have the same problem with the field of view is way of.

Tried it with trinusVR but is imposible to tweak all the angels ..until I find moonlight app and server .

The client connected instandly to the server on PC, no problem what so ever there.

So now only the field of view tweaking and all should be well !.

This again !!:thumbup:

now by trying this its not very clear what to change .

i change the left = 0.964925826 to half (and all others) with calculator and did this to all . but have no change in FOV.

the "left = 44.0º," . i can't find a setting that looks like that to set ti to that number .

no %

also "Which means your new horizontal FOV is 44.9º and new vertical FOV is 52.5º. " ??

would be nice if you more explainte step by step what to change and where to change it

thks in advance !!

Hey man, I suspect the changes had no effect for you because your DCS was in normal mode, not stereo mode. To put DCS in stereo mode you have to go inside DCS, in the Options, System tab and change "Monitors" from "1 Screen" to "Stereo". BUT as far as I remember, if you're using TrinusVR, you leave DCS in 1 Screen mode and the Trinus software should generate the stereo images. I might be wrong, I never used TrinusVR (my cell phone isn't compatible) and it's been a while since I've fiddled with VR.

As far as I remember, the image must be converted to stereo AND be treated to compensate for the lens distortion that occurs inside every VR headset. Without this compensation, you get the impression that the FOV is wrong when it isn't. As far as I remember (might be wrong), Trinus software should do not only the stereo images, but the lens compensation too. In the case of Oculs Rift and the Vive, I guess DCS does this automatically, but DCS must be in VR mode, not in "Stereo" mode. From what I remember, the image must be treated differently for each headset, because each one uses different lenses, distances to screen, etc.

Anyway, since I have Windows Phone and there's apparently no apps that do these things on Windows Phone, I gave up on playing VR on my phone. But, answering to your question:

also "Which means your new horizontal FOV is 44.9º and new vertical FOV is 52.5º. " ??

would be nice if you more explainte step by step what to change and where to change it

It means that, if you sum up left FOV + right FOV = 25.6º + 19.3º = 44.9º, that's total horizontal FOV. If you sum up top FOV + bottom FOV = 23.7º + 28.8º = 52.5º, that's total vertical FOV (but this all is assuming the numbers given in Stereo.lua are tangent of angles, and I have no means to confirm that).

the "left = 44.0º," . i can't find a setting that looks like that to set ti to that number .

no %

The default Stereo.lua file has, for the left eye:

Left = 
{
	x = 0;
	y = 0;
	width = screen.width * 0.5;
	height = screen.height;
	viewDx = 0;
	viewDy = 0;
	aspect = screen.aspect / 2;
	eye_shift = -0.032;
	--tans of side angles
	projection_bounds = { 
		left   = 0.964925826,
		right  = 0.715263844,
		top    = 0.889498115,
		bottom = 1.11092532,
},

you change it to:

Left = 
{
	x = 0;
	y = 0;
	width = screen.width * 0.5;
	height = screen.height;
	viewDx = 0;
	viewDy = 0;
	aspect = screen.aspect / 2;
	eye_shift = -0.032;
	--tans of side angles
	projection_bounds = { 
		[color="Red"]left = 0.48,
		right = 0.35,
		top = 0.44,
		bottom = 0.55,[/color]
	}
},

And for the right eye, the default Stereo.lua is:

Right = 
{
	x = screen.width * 0.5;
	y = 0;
	width = screen.width * 0.5;
	height = screen.height;
	viewDx = 0;
	viewDy = 0;
	aspect = screen.aspect / 2;
	eye_shift = 0.032;
	--tans of side angles
	projection_bounds = { 
		left   = 0.715263844,
		right  = 0.964925826,
		top    = 0.889498115,
		bottom = 1.11092532,
	}
}

you change it to:

Right = 
{
	x = screen.width * 0.5;
	y = 0;
	width = screen.width * 0.5;
	height = screen.height;
	viewDx = 0;
	viewDy = 0;
	aspect = screen.aspect / 2;
	eye_shift = 0.032;
	--tans of side angles
	projection_bounds = { 
		[color="Red"]left = 0.35,
		right = 0.48,
		top = 0.44,
		bottom = 0.55,[/color]
	}
}

Note that left and right bounds of the right eye are inverted in relation to the bounds of the left eye (your nose limits your FOV on the right of your left eye and on the left of your right eye).

Also remember these changes will only take effect if you change the option "Monitors" inside DCS from "1 Screen" to "Stereo".

Good luck with TrinusVR...