Jump to content
  • Advertisement
Sign in to follow this  
jdehaan

Aspect Ratio in 3D

This topic is 2498 days old which is more than the 365 day threshold we allow for new replies. Please post a new topic.

If you intended to correct an error in the post then please contact us.

Recommended Posts

Here's something I've always wondered about.

What kinds of things are going on when the same game is viewed in different aspect ratios? Is more of the scene present in widescreen than non-widescreen, or is the game written using one ratio and then scaled accordingly to match the new ratio?

I tried to look for this online, but I wasn't sure what to search for.

Thanks, guys!

Share this post


Link to post
Share on other sites
Advertisement
Well, the 3D side of things are completely independent of the display space. The only connection between the two are matrices, more importantly, the projection matrix. So that means the aspect ratio is usually defined by the projection matrix.

Now, to accomodate different aspect ratios, you could choose from several methids. One trick is to keep the vertical FOV (field of view) constant, and only change the horizontal FOV. Other method keeps the horizontal fixed and changes the vertical one. Or you could also use some combination of both.

Your real problem is the display resolution vs. the display aspect ratio. For example, the graphics card may expose a bunch of display resolutions with 4:3 aspect ratios, even though the display itself is 16:9 or 16:10. The reverse may also be true. By looking at the display mode list, there is no reliable way to know what physical aspect ratio the display uses, unless you do some OS specific queries about the display hardware and its native resolution. Even then, such info may not be available.

I guess your "fail safe" option is to allow your users to explicity chage the projection matrix aspect ratio, if needed.

Share this post


Link to post
Share on other sites
Sign in to follow this  

  • Advertisement
×

Important Information

By using GameDev.net, you agree to our community Guidelines, Terms of Use, and Privacy Policy.

GameDev.net is your game development community. Create an account for your GameDev Portfolio and participate in the largest developer community in the games industry.

Sign me up!