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raaaid
06-04-2007, 05:37 AM
i keep on thinking on my idea to improve the game with virtual reality via 6dof but im stuck on this:

you are looking at the moon through a window and the moon fits in the window exactly

the moon and window have the same APPARENT size

the moon takes 2º of your field of view so you know your field of view through the window is 2º

my question is: if you half distance to the window what will be your field of view through the window being initially 2º?

if you say 4º means that keeping halfing distance youl get fields of view superior to 360º

if you use trigonometry and say something like 3º how comes the window doesnt appear double big with half distance. i know its not double because if it was double there would be room for two moons together but being 3º theres no room for 2º two moons so its no doable

raaaid
06-04-2007, 05:37 AM
i keep on thinking on my idea to improve the game with virtual reality via 6dof but im stuck on this:

you are looking at the moon through a window and the moon fits in the window exactly

the moon and window have the same APPARENT size

the moon takes 2º of your field of view so you know your field of view through the window is 2º

my question is: if you half distance to the window what will be your field of view through the window being initially 2º?

if you say 4º means that keeping halfing distance youl get fields of view superior to 360º

if you use trigonometry and say something like 3º how comes the window doesnt appear double big with half distance. i know its not double because if it was double there would be room for two moons together but being 3º theres no room for 2º two moons so its no doable

Cajun76
06-04-2007, 05:58 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by raaaid:
i keep on thinking on my idea to improve the game with virtual reality via 6dof but im stuck on this:

you are looking at the moon through a window and the moon fits in the window exactly

the moon and window have the same APPARENT size

the moon takes 2º of your field of view so you know your field of view through the window is 2º

my question is: if you half distance to the window what will be your field of view through the window being initially 2º?

<span class="ev_code_YELLOW">if you say 4º means that keeping halfing distance youl get fields of view superior to 360º</span>

if you use trigonometry and say something like 3º how comes the window doesnt appear double big with half distance. i know its not double because if it was double there would be room for two moons together but being 3º theres no room for 2º two moons so its no doable </div></BLOCKQUOTE>

Don't know about most of this, but remember, math is a way of describing the physical world. Math can also go far beyond what is actually physically possible, although it's mathematically possible.

Say I fire an arrow at a target. If I halve the distance from arrow to target mathematically, then mathematically, the arrow will never reach the target. However, in the real world, it thunks into the bullseye, hopefully. http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

raaaid
06-04-2007, 06:05 AM
trigo says that if at 512m i have a field of view of 2º through the window at 256 ill have a field of view of maybe 3º

the problem with this is that itll mean that initially theres exact room for one moon and halving distance theres room for one and a half, 3º

this would mean that i see window 1.5 times bigger which would mean i decreased distance in a quarter not a half

im so stuck in this, even my father a mathematician cant help me

DaimonSyrius
06-04-2007, 06:11 AM
-When distance to your 'window' is infinite, the 'window' becomes a point and the field of view through it equals zero degrees.

-When distance to your 'window' is zero, you're level with it and the field of view 'through the window' equals 180 degrees. If you go further than that -going through the window- distance will increase again and the 'FOV through the window' will decrease correspondingly (and you will need to actually turn your head back in order to view anything at all 'through the window').

So, in your example 'FOV through a window' will vary with distance and can only take values ranging from 0 through 180. '360 degrees FOV through a window' isn't a meaningful concept.

Cheers,
S.

WhtBoy
06-04-2007, 06:25 AM
Trigonometry says that the angle an object subbtends across your retina is equal to the following...

2*ATAN((y/2)/x)

Where...

y=width of object
x=distance to object

It's as simple as that. It approaches 180 degrees as the distance x approaches 0. End of story.

--Outlaw.

raaaid
06-04-2007, 06:47 AM
ive spent years and made thousands of drawings on perspective looking for a flaw or paradox and think finally found it:

draw a square and a circle the same size, thats the moon and the window

now make a drawing of what you would see halving distance to the window

moon will be same size than before,same circle

the question is the size of the window now?

obviously as you has halved distance to it it appears doble size so you should draw a square double big than the circle

but double big means double field of view because now you can draw 2 moons of 2º each inside the square and if each time you half distance you double fov you may be halving distance forever reaching far than 180º fov

if you give it the trigo approach and say halving distance the square is more or less 3º while the circle 2º youll draw the square 1.5 times bigger than the circle

then this contradicts half distance double apparent size because by halving distance to window you see it just 1.5 times bigger not two which would lead to think you reduce distance to window in a quarter not a half as you did

Philipscdrw
06-04-2007, 06:49 AM
Forget the trig. If you move closer to a window, it'll take up more and more of your field-of-view, until your face is against the glass, and the window's taking up 180? of your view. Keep moving forwards, through the window, and the window will take up less of the field-of-view, and you fall towards the ground.

This can be explained with trig but I can't be bothered to make the necessary MSPaint diagrams and upload them...

Philipscdrw
06-04-2007, 06:50 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by WhtBoy:
Trigonometry says that the angle an object subbtends across your retina is equal to the following...

2*ATAN((y/2)/x)

Where...

y=width of object
x=distance to object

It's as simple as that. It approaches 180 degrees as the distance x approaches 0. End of story.

--Outlaw. </div></BLOCKQUOTE>

edit: what do you mean, 'if you go for the trigo approach'? There's only one way to calculate the field-of-view angle and that's with trigonometry!

WhtBoy
06-04-2007, 06:56 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by raaaid:
ive spent years and made thousands of drawings on perspective looking for a flaw or paradox and think finally found it:
</div></BLOCKQUOTE>

raaaid,
Do you agree that the equation I posted accurately calculates the angle an object subtends on a person's retina? If not, WHY NOT?

--Outlaw.

raaaid
06-04-2007, 07:22 AM

my question is extreamly simple

initially i draw the window and moon as a square and circle the same size

i half distance to the window so i draw the moon same size than before...

but what size do i draw the square now?

awaiting anxiously your answer because its whats confusing me about developing my idea on VR with 6dof

WhtBoy
06-04-2007, 07:52 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by raaaid:
</div></BLOCKQUOTE>

What's not to understand about the equation? It's as simple as plugging in numbers! You know the size of the object and you know the distance. What is so hard about that?

--Outlaw

raaaid
06-04-2007, 07:53 AM
this question has only one sensible answer:

you half distance to it so now you draw it double big(this is the main axiom in perspective drawing)

so now i can draw 2 moons within the window

i half distance again so window size doubles again now i can draw 4 moons

half again 8 moons, another half 16 moons,32 moons 64 moons 128 moons

if each moon takes a field of view of 2º thats too many moons for a 180º max fov

plz attain to drawing rules

raaaid
06-04-2007, 07:54 AM
i think vision to be one of the most misterious phenomena i dont think it can be reduced to one equation anyway ill try to understand it

WhtBoy
06-04-2007, 08:21 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by raaaid:
i think vision to be one of the most misterious phenomena i dont think it can be reduced to one equation anyway ill try to understand it </div></BLOCKQUOTE>

What part of the equation don't you understand?

--Outlaw.

LEBillfish
06-04-2007, 08:26 AM
http://img.photobucket.com/albums/v707/Kaytoo/lures.jpg

Done this same discussion like 20x here.... http://forums.ubi.com/images/smilies/shady.gif

raaaid
06-04-2007, 08:37 AM
yeah i reached that equation by myself you are right

but thats the angle but we see the projection of that angle in a surface, double big on the surface is not double angle

so if initially i have a field of view trough the window of 2º halving distance according this equation will be something similar to 3º

but as i dont draw angles but a projection of that angle in a surface the 3º projection will appear double size than the 2º projection on the surface

so the answer according your equation is that i have to draw the square(window) double big than before

the contradiction lyes in which now i can fit two moons in the square and i know for sure each moon takes a field of view of 2º, and 2º and 2º makes 4º

so trigonometrically i reach the conclusion that the field of view when halving distance increases 1.5 times which makes the projection on a surface double big

but on the other hand if i use the moon as a reference i reach the conclusion that the field of view has doubled which contradicts trigo

DaimonSyrius
06-04-2007, 08:40 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by raaaid:
this question has only one sensible answer:

you half distance to it so now you draw it double big(this is the main axiom in perspective drawing) </div></BLOCKQUOTE>

Wrong axiom.
Trigonometric functions like tangent or arcsine are not linear.
See Angular diameter (http://en.wikipedia.org/wiki/Angular_diameter) and Inverse trigonometric function (http://en.wikipedia.org/wiki/Inverse_trigonometric_function).

Also check Perspective (graphical) (http://en.wikipedia.org/wiki/Perspective_%28graphical%29)
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">The artist Giotto di Bondone attempted drawings in perspective using an algebraic method to determine the placement of distant lines. The problem with using a linear ratio in this manner is that the apparent distance between a series of evenly spaced lines actually falls off with a sine dependence. To determine the ratio for each succeeding line, a recursive ratio must be used. This was not discovered until the 20th Century, in part by Erwin Panofsky. </div></BLOCKQUOTE>

Cheers,
S.

P.S.: BTW, the angle subtended by the full Moon is actually 30' (half a degree), not 2 degrees.

Philipscdrw
06-04-2007, 08:51 AM
So basically half distance IS NOT double field-of-view angle.

raaaid
06-04-2007, 08:54 AM
yeah i was wondering what the angular diameter of moon was, its 0.5º

obviously if i half distance to moon its angular diameter wont be 1º but more close to 0.7º

but a drawing is a projection of that angular diameter on a surface and a projection on a surface of a 178º angle might be half big than one of 179º as the 1º projection on a surface might be double size than a 0.7º

and the projection on a surface doubles as the distance halfs, see tales proportional triangles

WWSensei
06-04-2007, 08:59 AM
I think he's just fishing or trolling as he has had this exact same concept explained to him at least 3 or 4 other times.

He keeps claiming he's found a flaw in physics or science when in reality he just shows a profound ignorance of even simple mathematical concepts. Can't find something on Google? Worldwide conspiracy to keep him from info when in reality he just really sucks at using Google.

I have little patience for someone who, once shown their error simply refuses to believe it and continues asking the same questions over and over again. Having an inquisitive mind is good. Refusing to learn is not.

I've come to the conclusion he isn't after any real answers to his questions he is just trying to pretend to be some deep thinker and lives off the attention thinking people must think him clever. Worked at first but when you see the exact same question being posed again and again without acknowledging how he has been shown to be wrong every single time you just realize he is a poser with little knowledge of what he is talking about and little desire to really learn.

AKA_TAGERT
06-04-2007, 09:01 AM
Only one equation you need to remember in day to day life..

&lt;18 will get you 20.

Philipscdrw
06-04-2007, 09:09 AM
hmm.

I've just calculated this...

if something has angular diameter 0.5?, and you halve the distance, the new angular diameter is 0.99998?.

If something has angular diameter 60?, if you halve the distance it becomes 98.2?. I think. Didn't work it out properly though. Windows Calculator leaves much to be desired...

raaaid
06-04-2007, 09:11 AM
so if you are saying halving distance to the window means not drawing it double big explain me this:

at 200 m a fighter will fill half gunsight at 100 m it will fill full gunsight

doesnt this prove that when you half distance to something you draw it double big?

of course the angle of view doesnt double

but if initially the window and moon has an angular diameter of 0.5º when i half distance to the window i must draw it double big so now i can draw two moons which makes 1º which contradicts trigonometry

Philipscdrw
06-04-2007, 09:16 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by raaaid:
so if you are saying halving distance to the window means not drawing it double big explain me this:

at 200 m a fighter will fill half gunsight at 100 m it will fill full gunsight

doesnt this prove that when you half distance to something you draw it double big?

of course the angle of view doesnt double

but if initially the window and moon has an angular diameter of 0.5º when i half distance to the window i must draw it double big so now i can draw two moons which makes 1º which contradicts trigonometry </div></BLOCKQUOTE>
That's because the gunsight uses Mercator projection so you can accurately calculate the angle of deflection, but the side-effect is that it distorts the apparent view.

raaaid
06-04-2007, 09:21 AM
i guess you are joking you never know here

the angular diameter of the circle of a reflective gunsight is constant however head distance to it

thats why theyr usefull to judge distances

Philipscdrw
06-04-2007, 09:42 AM
Sorry, my bad. The gunsight uses standard coaxial projection, it's Il-2's display on the screen that uses Mercator projection. That's why this apparent effect is caused.

raaaid
06-04-2007, 09:48 AM
yeah right so i prove half distance double apparent size which nobody admitts and the conversation changes to laugh at me

BSS_Goat
06-04-2007, 09:50 AM

LStarosta
06-04-2007, 09:52 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by AKA_TAGERT:
Only one equation you need to remember in day to day life..

&lt;18 will get you 20. </div></BLOCKQUOTE>

Blackjack reference?

jk

LStarosta
06-04-2007, 09:55 AM
Raid, if you know the answer to everything, then why do you post questions on a flight simulator forum? To ridicule everybody else?

Blood_Splat
06-04-2007, 10:20 AM
Lets just leave this to the developers lol.

XyZspineZyX
06-04-2007, 10:31 AM
If we are talking *apparent* size, then there's really no need for debate

Just draw out your diagram, and see if it's true or not. All you need to know is the length of the tube and the ID of both ends, and how far away from the tube your eye is

Drawing out diagrams is fairly easy, and really helps with things like this http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

fordfan25
06-04-2007, 11:18 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by BBB462cid:
If we are talking *apparent* size, then there's really no need for debate

Just draw out your diagram, and see if it's true or not. All you need to know is the length of the tube and the ID of both ends, and how far away from the tube your eye is

Drawing out diagrams is fairly easy, and really helps with things like this http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif </div></BLOCKQUOTE>thats what she said!

raaaid
06-04-2007, 11:37 AM
ive just done a diagram and ive found out that if initially the moon and window appear the same size when you half distance to window moon will be same apparent size and window will be double apparent size than prior

but what confuses me is that now i can draw two moons and if i half again four moons and keeping on that makes more than 180º

this oddity probably comes from distance to moon not varying noticiable

Philipscdrw
06-04-2007, 11:49 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by raaaid:
ive just done a diagram and ive found out that if initially the moon and window appear the same size when you half distance to window moon will be same apparent size and window will be double apparent size than prior

but what confuses me is that now i can draw two moons and if i half again four moons and keeping on that makes more than 180º

this oddity probably comes from distance to moon not varying noticiable </div></BLOCKQUOTE>

Raaaid, if you walk through the window and the window is behind you, the window isn't taking up more than 180? of your forward view, the window is taking up less than 180? of your rear view.

Hawgdog
06-04-2007, 01:23 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by raaaid:
i keep on thinking but im stuck on this:

</div></BLOCKQUOTE>

http://forums.ubi.com/images/smilies/88.gif

WhtBoy
06-04-2007, 01:36 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by raaaid:
ive just done a diagram and ive found out that if initially the moon and window appear the same size when you half distance to window moon will be same apparent size and window will be double apparent size than prior

but what confuses me is that now i can draw two moons and if i half again four moons and keeping on that makes more than 180º

this oddity probably comes from distance to moon not varying noticiable </div></BLOCKQUOTE>

OMG are you serious??? Were you really attempting to determine the field of view angle as a function of the apparent size of an object whose distance changed on the order of 1E-9 as compared to an object whose distance was halved?!?!?!?!?!?!?!?!?!?!?!?!?!

--Outlaw.

DuxCorvan
06-04-2007, 01:53 PM
Now I get what it means, 'mindwanking'.

raaaid
06-04-2007, 01:59 PM
haha i swear to god i was expecting someone to say that

Cajun76
06-04-2007, 11:08 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by WhtBoy:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by raaaid:
ive just done a diagram and ive found out that if initially the moon and window appear the same size when you half distance to window moon will be same apparent size and window will be double apparent size than prior

but what confuses me is that now i can draw two moons and if i half again four moons and keeping on that makes more than 180º

this oddity probably comes from distance to moon not varying noticiable </div></BLOCKQUOTE>

OMG are you serious??? Were you really attempting to determine the field of view angle as a function of the apparent size of an object whose distance changed on the order of 1E-9 as compared to an object whose distance was halved?!?!?!?!?!?!?!?!?!?!?!?!?!

--Outlaw. </div></BLOCKQUOTE>

I'll let your loved ones know that you've entered the mind of raaaid.

CanonUK
06-04-2007, 11:19 PM
I've just done some diagrams and I've discovered that 'raaaaid' talks a load of ****...

If I double the amount of **** raaaaid talks but half the amount of attention I give it, does the amount of **** raaaaid talks half?

Blah, blah, blah..

http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

raaaid
06-05-2007, 06:20 AM
thanks to the game i found the answer:

the gunsight is the moon, when is in a side of the screen is bigger than when in the center

thats because the 10º angular diameter projects bigger when is on a side of the paper(screen) because the incidence of the angle is leaning on the surface contrary to when its in the center that is vertical, the more leaning the more the angle will expand

Yellonet
06-05-2007, 06:45 AM
Here's an idea, why not just test it out. It's not really a difficult experiment is it http://forums.ubi.com/images/smilies/shady.gif

Freelancer-1
06-05-2007, 06:55 AM
Raaaid try thinking of it this way:

The monitor is not a window you are looking through. The monitor is your eyes.

Therefore FOV will not change relative to the monitor as you get closer.

Using the cockpit frame as the window you will see the apparent FOV change as it should as you approach the target.

I think if you look at it this way you will realize that your 'window and moon' equation works as advertised http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif

WhtBoy
06-05-2007, 12:36 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Freelancer-1:
Raaaid try thinking of it this way:

The monitor is not a window you are looking through. The monitor is your eyes.
</div></BLOCKQUOTE>

He's been told this multiple times but he's still obsessed with the idea. It's mostly based on his incorrect belief of how the TrackIR works. Similarly, it's been explained to him that the TrackIR does NOT work the way he thinks it does and thus, his whole concept is bunk, but he continues. It's amazingly funny.

--Outlaw.

raaaid
06-06-2007, 06:16 AM
when cinema appeared and espectators were shown a train coming everybody stood up and run away

they thought the screen was a window

im pretty sure in less than ten years my idea for VR via 6dof will be in every trackir game

easy to do and more realistical than now just like panning with the mouse

do you think that mouse panning was an idea by a programmer, no it was probably the idea of a player and as it was good now every single game has it