45 replies to this topic

[Adridos]

Phaesphoros, on 09 April 2013 - 05:56 AM, said:

Btw: CryEngine's default FoV value is 60°.

Default FPS game FOV is 90°.

[Phaesphoros]

Adridos, on 09 April 2013 - 06:11 AM, said:

Default FPS game FOV is 90°.

Download CryEngine. Use either Sandbox or the example game. In example game, drop down console by pressing `. Enter cl_fov (+Enter). Observe it says 60 (°) like in the docs.

As p00k pointed out, CryEngine might use a vertical FoV instead of a horizontal, 60° vertical is equal to about 90° horizontal. I'm still trying to figure out whether it's horizontal or vertical in CryEngine, the docs are not very useful.

[Adridos]

Phaesphoros, on 09 April 2013 - 06:18 AM, said:

Download CryEngine. Use either Sandbox or the example game. In example game, drop down console by pressing `. Enter cl_fov (+Enter). Observe it says 60 (°) like in the docs.

I believe you on the fact of how much FoV does Cry Engine 3 have.

All I'm saying is that the standard is 90° and every game should have the option to get at least close to it.

[Henree]

Egomane, on 08 April 2013 - 03:56 PM, said:

There is one little problem with your post.

Your personal perfect value for FoV of 50 is invalid in this game. It is to low. I believe the minimum was 60 or 65. Need to look it up again (if needed), as the restriction was made a few months back.

There is one little problem with your post.
GRAMMAR!

[Adridos]

Also, I have no idea how horizontal FoV behaves when you can only change vertical FoV, but...

http://www.rjdown.co...vcalculator.php

[Phaesphoros]

Adridos, on 09 April 2013 - 06:27 AM, said:

Also, I have no idea how horizontal FoV behaves when you can only change vertical FoV, but...

http://www.rjdown.co...vcalculator.php

That is no problem, as the resolution of your screen fixes the relation between horizontal and vertical FoV. That is, you only need either horizontal OR vertical FoV (they're redundant).

[Urfin]

Yeah, problem with FOV in a bit fewer words is much simpler - 50-60 (horizontal) is ok for the console-living-room-big screen setup, and it sucks on a 24 inch PC screen that's in your nose, for which 90-110 is bettah.

Also, FOV sickness from lack of expected stuff in peripheral vision when FOV is lower than it should be is actually a thing

Edited by Urfin, 09 April 2013 - 06:48 AM.

[Elizander]

Liking it cause it has pictures n' fancy terms n' stuff!

[Corvus Antaka]

Did not read massive wall of text.

[Morang]

Posting in epic thread!

Phaesphoros, on 08 April 2013 - 03:46 PM, said:

Size & scale

The problem is, that the virtual world does have a right scale. A tree in the virtual world is 15 virtual metres high (or whatever), a pilot is about 2 virtual metres tall. And what you should see on your screen are 15 real metres high trees and 2 real metres tall pilots. If the size of the window of the virtual camera cannot be adjusted to the size of your real-life screen, there's only one screen size so that the virtual world objects look realistically sized.
If that's the 0.5 m width of the first two players, then the P2W player #3 will see trees that are 45 m high and huge 6 m pilots.

But how do we know that right scale with fixed camera window is achieved when viewing through 0.5 m screen, not 1.5 m? It looks like we should 1) set up realistic FOV (corresponding with our screen size and distance to player), 2) pick an object of known scale at known distance in game world, 3) calculate its angular size and see if it will be equal to angular size of real object of the same size at the same distance IRL. And if it is, then our screen size is the "sweet spot". Maybe it's not Mr P2W sees huge mechs, but ordinary players see them shrinked?

I tried realistic FOV in testing grounds (35 degrees vertical cl_fov for approx 50 cm distance from 30 cm high screen). It appeared to me that hands of my avatar sitting in the cockpit were much smaller than my own hands on keypad and mouse. I have 1680x1050 22" screen. Perhaps it will be better to measure more distant and larger objects outside of cockpit, I'll try that evening.

Edited by Morang, 12 April 2013 - 01:12 AM.

[Phaesphoros]

Morang, on 11 April 2013 - 10:30 PM, said:

But how do we know that right scale with fixed camera window is achieved when viewing through 0.5 m screen, not 1.5 m?

What I did was an example. You're right with:

Morang, on 11 April 2013 - 10:30 PM, said:

Maybe it's not Mr P2W sees huge mechs, but ordinary players see them shrinked?

But we cannot do anything to adjust it *shrug*

Morang, on 11 April 2013 - 10:30 PM, said:

I tried realistic FOV in testing grounds (35 degrees vertical cl_fov for approx 50 cm distance from 30 cm high screen).

I wonder how you did that? AFAIK devs restricted FoV to >= 60° vertical..

Morang, on 11 April 2013 - 10:30 PM, said:

Perhaps it will be better to measure more distant and larger objects outside of cockpit, I'll try that evening.

Sounds interesting!

[Morang]

Ah, I just checked. Looks like guys with large monitor won't have their virtual world enlarged. The scale is always correct.

Let's imagine a Cataphract standing in front of our cockpit rangefinder at 100 virtual meters. Additional real distance to monitor, be it .25 or .75 meters, won't make much difference there. So it's at 100 meters. When I just selected vertical virtual FOV of 60, on my screen of 29.6 cm height Cataphract had real height of 4.1 cm. If I want my real FOV to be equal to virtual, I must observe my 29.6 cm screen with 60 FOV from 25.63 cm = 29.6 / 2 tan (60/2).

So, to get the "virtual" height of Cataphract all I need is to make an equation: Cataphract image size/Screen viewing distance = Cataphract in-game size/In-game distance (don't forget, all in meters! viewing distance = 0.2563, image size = 0.041). It gives us the height of Cataphract = 16.19 meters.

If I will use three times larger screen, nothing will change for Cataphract at 100 meters. With same FOV I'll be viewing the screen from the 3x distance and observe 3 times larger image of the Cataphract, but with same angular size and relation of image size to viewing distance. Cataphract will still be 16 meters high in game - NOT 48 meters!


So, why Mr P2W can't see more?
Because in your example you moved your viewer wrong. You pulled him back from the screen, while you shoud've pushed the screen inside the virtual world.



See what happens here. Neither sizes of virtual objects nor distances from player to them haven't changed. Larger screen though is showing the green ball as if it were closer to the viewer than the screen plane itself. It's not impossible at all. This is just a projection.

Edited by Morang, 12 April 2013 - 07:32 AM.

[Morang]

Phaesphoros, on 12 April 2013 - 04:46 AM, said:

I wonder how you did that? AFAIK devs restricted FoV to >= 60° vertical..

You're right, I was wrong. I was just accustomed to larger FOV when ususally playing and thought I was there. Actually the limit is 60, just checked on my screen with ruler. Glad I took my measurements of game objects at 60, I thought about doing it at "45" at first. No recalculations needed.

My results are:

Battlemech height:
Commando 9.75 m
Cicada 13.66
Centurion 15.8
Catapult 16.78
Cataphract 16.19
Awesome 17.36
Atlas 27.3 - looks like oversized. So much for intimidation.

Dropships
Leopard dropship legth: 214.6 meters (two measured - Tourmaline w/o nose and Frozen with broken hull. I extrapolated the lenght of undamaged from them).
Aerodyne (not Leopard, it seems) at upper base in River City length 277.8 m
Mammoth ring horisontal diameter 327.7 m

Ground vehicles
Mining crawler 47.8 m long, 18.7 m high (cabin)
River City transportation:
3-axle wagon 9.75 m
minivan+trailer 7 m + 11.9 m
family sedan 5.1 m

4-lane bridge is 20 m wide.

Buildings in Forest Colony:
Container shelter (single level) 5.65 m high.
Two-story building with roller gate near the center 17.3 m high
Comms Tower near the cave: 167 m high, less antennas.
HPG dish longer axis 183 m
HPG dish antenna 209 m long

Derelict container ship an Forest Colony length about 350 m

Buildings in Frozen City:
One block with well defined storeys gives storey height of 3.9 m
Street lamp post in Frozen City harbor (not buried in ice) 7.8 m high

Derelict ship at Frozen City, bridge width (and, I suppose, ship's beam) 34.3 m

Buildings in River City:
5 storey with high cellar 27.3 m
6 storey 38.62 m
12 storey glass facade 40.6 m


Trees at Forest Colony. Two average measured, green and dead. 29 and 24 meters.
Largest tourmaline towers (near bases) 700-800 m high (they're just out of bounds). One of ordinary inclined and climbable tourmaline aggregates: 210 m along crystals' axis.
Drilling rig at base: 32 high less antennas, approx 26-27 wide

Edited by Morang, 12 April 2013 - 07:15 AM.

[Phaesphoros]

Morang, on 12 April 2013 - 06:00 AM, said:

Ah, I just checked. Looks like guys with large monitor won't have their virtual world enlarged. The scale is always correct.

I like your analysis, but I have some questions/objections.

Morang, on 12 April 2013 - 06:00 AM, said:

So, to get the "virtual" height of Cataphract all I need is to make an equation: Cataphract image size/Screen viewing distance = Cataphract in-game size/In-game distance (don't forget, all in meters! viewing distance = 0.2563, image size = 0.041). It gives us the height of Cataphract = 16.19 meters.

Didn't check en detail, but the calculation looks correct to me. Though, I'd rather say the result is "16.19 virtual meters", as you still don't know the scale between real-world meters and virtual-world meters. If the unit in-game was inch but called meter, you'd end up with "16.19 inch", therefore the distinction between real-world and virtual-world meters.

Morang, on 12 April 2013 - 06:00 AM, said:

If I will use three times larger screen, nothing will change for Cataphract at 100 meters. With same FOV I'll be viewing the screen from the 3x distance and observe 3 times larger image of the Cataphract, but with same angular size and relation of image size to viewing distance. Cataphract will still be 16 meters high in game - NOT 48 meters!

Imagine you change the FoV in-game, continuously like when you zoom. There is more than one possibility how the game / the engine could handle that; as I've stated earlier, there's at least one information missing.
Two examples:

• You keep the size of the virtual window the same for all FoV values. What I mean with "size of the virtual window" is the size of the view frustrum at focus distance (where, e.g. the DoF converges to form a sharp/focused picture). In that case, you can e.g. keep either the position of the camera or the position of the virtual window fixed when changing FoV. The scale of the objects doesn't change
  
• You keep the focus distance fixed. In that case, the size of the virtual window changes, and the scale of all objects accordingly.

As the game doesn't know about your screen's DPI / its size, it cannot know what the right scale is between real-world and virtual-world coordinates. All the game can do is to map virtual-world angles to real-world pixels (but of course, the pixels can have different sizes).

Morang, on 12 April 2013 - 06:00 AM, said:

So, why Mr P2W can't see more?
Because in your example you moved your viewer wrong. You pulled him back from the screen, while you shoud've pushed the screen inside the virtual world.

I moved him according to the example I wanted to express. One could argue that the real-world screen setup should not affect the position of your avatar in a FPS, I grant you that. But you can argue as well that your screen IS like a portal (or window) to the virtual world, and then you HAVE to move the camera; this is shown in the example / pic I've posted.

I think the main point still holds: the game cannot use the right scale for all screen setups, as you can either move closer to the screen or change the screen size - and in both cases the same FoV might result.

Edited by Phaesphoros, 12 April 2013 - 09:51 AM.

[Zaptruder]

Wow... why are such simple concepts made so obtuse in this thread?

Increase FOV = see more of the cockpit and field. Objects become smaller on screen.
Decrease FOV = see less of the cockpit and field. Objects become larger on screen.

Larger screen size @ same seating distance = objects become larger to viewer.

Orthographic view = objects on screen appear scaled to real life objects (i.e. the hands of the mechwarrior should appear as the same size as your hands). This varies depending on screen size and seating distance. Ideally screen is at arms length or less from viewing position to achieve best orthographic illusion.

Edited by Zaptruder, 12 April 2013 - 10:01 AM.

[Morang]

Phaesphoros, on 12 April 2013 - 09:51 AM, said:

As the game doesn't know about your screen's DPI / its size, it cannot know what the right scale is between real-world and virtual-world coordinates. All the game can do is to map virtual-world angles to real-world pixels (but of course, the pixels can have different sizes).

Yes, that's why it can't do the trick you've shown with large screen - adjust angles, taking into consideration real-world distance from viewer to the screen and real-world screen dimension.

Quote

I think the main point still holds: the game cannot use the right scale for all screen setups, as you can either move closer to the screen or change the screen size - and in both cases the same FoV might result.

As we maintain our real FOV equal to virtual FOV, screen size doesn't matter - it's always compensated by viewing distance. Our eye (assuming we have one) is always in the same spot where virtual camera is. Let's imagine virtual object that has angular size equal to our virtual FOV (e. g. 60 degrees). Game draws it from top to bottom of the screen. And as we purposefully positioned our head so that real angle between our line of sight to the top of the screen and our line of sight to the bottom of the screen is 60 degrees too, for us the real-world length of pixels representing this object will have the same 60 degrees angular size.

Now on scale. When we see real image of the virtual object, filling our 60 degrees FOV, we can't decide by ourselves virtual size of this object and virtual distance to it. Real size of the screen and real viewing distance doesn't matter, as they are only relevant for real image of the virtual object. About virtual object we only know the angle at which the game wants to map it for us. You told yourself that the game only maps virtual world angles.

So only the game itself can tell us which scale is right. Because image of 16 virtual meters high Cataphract 100 virtual meters away and image of 16 virtual inches high Cataphract 100 virtual inches away and image of 16 virtual miles Cataphract 100 virtual miles away will all look exactly the same on the same screen. When the game tells that the unit is called meter, it gives you the scale.

[jay35]

At the end of the day, all that matters is that the game provides a slider or exposes a variable that allows players to choose the fov that works best for them within the common range of fov, which is (excluding zoom modes) 65-105 degrees.

[Phaesphoros]

@Morang: There's more truth in what you said than I originally noticed.

Morang, on 12 April 2013 - 06:00 AM, said:

See what happens here. Neither sizes of virtual objects nor distances from player to them haven't changed. Larger screen though is showing the green ball as if it were closer to the viewer than the screen plane itself. It's not impossible at all. This is just a projection.

Left picture: What you actually do (in real world) when you change your screen.
Right picture: What is "done" (assumed) by the FPS; actually, nothing is done (same FoV).

The focus distance is not as important as I originally stated, it does as well define the scale of objects - in such a way that if you change both the focus distance and size of the window, nothing happens to the projection on your screen. But although the objects still will look correctly scaled (it isn't the correct scale actually, see below), the situation the FPS assumes does not match the real-world screen setup. When you reduce your FoV value in MWO, it looks like you move closer to the windshield of your mech, that's what happens when you keep the camera position constant. It's like your avatar pilot looks through a "picture frame" and moves this frame to the windshield - it further reduces the peripheral vision, that is, what you see to the sides of your mech (additionally to the FoV effect on peripheral vision).

If you include either head-tracking or stereoscopy (or both), the actual focus distance will become important on its own. While you can still fix head-tracking by supplying your head's coordinates to the game in fractions of your screen width, for stereoscopy the eye distance is important, and it's very much fixed at 7 real-world cm. By supplying the game with the eye distance as a fraction of the screen width, you effectively do supply a scale between real-world and virtual-world coordinates.

Example for head-tracking: Imagine what happens if, in real life, you go to a window and move your head horizontally a distance X as defined below. Repeat that with a smaller window with same FoV. The effect is the same if X := fraction of the respective window size, but it's not the same if X := fixed number of meters.

Example for stereoscopy: You'll need 2 cameras here, one for each eye. The distance between the two is the same, 7 cm, for all screen sizes and FoVs. It's a smaller fraction of the screen width if your screen is small, therefore, stereoscopy depends on an additional information to get the scale right.

Edited by Phaesphoros, 12 April 2013 - 01:50 PM.

[moneyBURNER]

The screen simulates the point of view of your virtual eyes, not a window into the virtual world for your real eyes, so your physical distance to the screen is only relevant for personal comfort. It would be ridiculous to treat the screen as an actual window while most people are still using one 24" screen from 2+ feet away.

[Phaesphoros]

moneyBURNER, on 12 April 2013 - 02:01 PM, said:

The screen simulates the point of view of your virtual eyes, not a window into the virtual world for your real eyes, so your physical distance to the screen is only relevant for personal comfort. It would be ridiculous to treat the screen as an actual window while most people are still using one 24" screen from 2+ feet away.

Umm...... your actual distance to your screen determines the perspectively correct FoV, which is unfortunately ignored in favor for better peripheral vision in FPS. In other 3D applications (movies, or where your camera rather belongs to an observer), you'll more likely set the virtual camera's FoV to match the FoV of your screen better.
The perspective projection, i.e. the method used to flatten the 3D objects onto the screen's 2D surface, is actually based on the idea to treat the screen as a window to the virtual world.