Java-Gaming.org Hi !
 Featured games (84) games approved by the League of Dukes Games in Showcase (564) Games in Android Showcase (151) games submitted by our members Games in WIP (605) games currently in development
 News: Read the Java Gaming Resources, or peek at the official Java tutorials
 Home Help Search Login Register
Pages: [1]
 ignore  |  Print
 Calculating horizontal FOV  (Read 1011 times) 0 Members and 1 Guest are viewing this topic.

Junior Devvie

Java games rock!

 « Posted 2004-09-17 14:16:22 »

Hi,

is there anyone who can tell me how to calculate horizontal FOV ?

What I want is to place in object attached to the visible bounds of the view. Now, the upper and lower bounds of the view can be calculated simply rotating the view transform by either FOV or -FOV for upper or lower bound.

However, now I have the problem of doing the same for the left and right side. My first thought was to use the canvas aspect ratio as a factor for the FOV value (e.g. 1.3333f for 4:3 canvas). But with this value the object is outside the view. For a 4:3 canvas the magic number is around 1.25 instead. In a square 1:1 canvas it works of course without correction.

any ideas on how to get the correct factor for the horizontal FOV ?

thanks,
ewills

Junior Devvie

Java skeletal animation systems rock!

 « Reply #1 - Posted 2004-09-17 19:54:54 »

width/height = hfov/vfov, so hfov = vfov*(width/height).  So you want an object that remains fixed in front of the view?  It sounds like a Foreground node might be the solution.
William Denniss

JGO Coder

Projects: 2

Fire at will

 « Reply #2 - Posted 2004-09-17 22:44:57 »

I need to do this too - I've positioned my Foreground nodes fine for 4:3 but if the user changes the width of the window, they stay where they are.

Will.

 Games published by our own members! Check 'em out!
ewills

Junior Devvie

Java skeletal animation systems rock!

 « Reply #3 - Posted 2004-09-20 02:11:28 »

So you want to keep HUD objects a fixed distance from the left and right edges of the screen?  Can you split the HUD into distinct objects and manage their translations?  If fov remains constant, oldX/oldWidth = newX/newWidth should hold.
William Denniss

JGO Coder

Projects: 2

Fire at will

 « Reply #4 - Posted 2004-09-20 21:16:23 »

yes, my problems are only when the fov changes.  However, this can be common.  For example, my mac has a wide-screen but my PC a 4:3.  Games such as Warcraft still look great on the wide-screen infact you actually see more of the game thus have a slight advantage!  (my brother was not happy when we worked this out, lol).

If I make my game screen wider - the hud elements stay where they are.  They are distinct objects and can be moved, I just need to make them do it.

Will.

Pages: [1]
 ignore  |  Print

You cannot reply to this message, because it is very, very old.

 theagentd (9 views) 2015-03-27 23:08:20 wxwsk8er (52 views) 2015-03-20 15:39:46 Fairy Tailz (43 views) 2015-03-15 21:52:20 Olo (28 views) 2015-03-13 17:51:59 Olo (30 views) 2015-03-13 17:50:51 Olo (35 views) 2015-03-13 17:50:16 Olo (40 views) 2015-03-13 17:47:07 ClaasJG (32 views) 2015-03-10 11:36:42 ClaasJG (39 views) 2015-03-10 11:33:01 Pippogeek (47 views) 2015-03-05 14:36:23
 LiquidNitrogen 23x BurntPizza 21x KevinWorkman 21x basil_ 20x Riven 18x EgonOlsen 17x theagentd 16x princec 12x Roquen 12x Varkas 10x SHC 9x NegativeZero 9x teletubo 7x Ecumene 7x nsigma 7x wessles 7x
 How to: JGO Wikiby Mac702015-02-17 20:56:162D Dynamic Lighting2015-01-01 20:25:42How do I start Java Game Development?by gouessej2014-12-27 19:41:21Resources for WIP gamesby kpars2014-12-18 10:26:14Understanding relations between setOrigin, setScale and setPosition in libGdx2014-10-09 22:35:00Definite guide to supporting multiple device resolutions on Android (2014)2014-10-02 22:36:02List of Learning Resources2014-08-16 10:40:00List of Learning Resources2014-08-05 19:33:27
 java-gaming.org is not responsible for the content posted by its members, including references to external websites, and other references that may or may not have a relation with our primarily gaming and game production oriented community. inquiries and complaints can be sent via email to the info‑account of the company managing the website of java‑gaming.org