Explanation on horizon/ground blending?

[andrewrpreza]

Hello,

 

This is my first post here, decided to join because i've been looking around on how to solve my problem and even though I find the "concepts" on how to do it, I still don't know how to approach it.

 

I was asked to do a flyover on an apartment complex. My problem is that I can't find a good way to make the horizon infinite where it meets with the ground.

 

As I understand it, the skydome method is quite antiquated and the common method today is to use a high res HDRI and just make the ground blend with it on the horizon by using falloff maps.

 

So, does anyone have a link to a tutorial or documentation that explains this a bit further?

 

This is an example on what I mean:

 

 

Thanks for your time.

 

-Andrew

[Devin Johnston]

Most render engines come with a physical sun/sky, the easiest way to get an infinite horizon is to use this.

[andrewrpreza]

Most render engines come with a physical sun/sky, the easiest way to get an infinite horizon is to use this.

 

 

No, yes... I know that.

 

I'm talking about a seamless blend between the horizon and ground.

 

[Peter M. Gruhn]

Not sure what you mean. The area highlighted in the picture shows a horizon completely covered by buildings. "seamless blend" and "covered up" are not the same in my mind. Maybe you are looking at the haze/fog?

[andrewrpreza]

Not sure what you mean. The area highlighted in the picture shows a horizon completely covered by buildings. "seamless blend" and "covered up" are not the same in my mind. Maybe you are looking at the haze/fog?

 

Well I guess technically "seamless blend" and "covered up" are not the same, but they are still used to solve the same problem, right?

 

For example, when talking about using fog/haze to cover up the horizon, a lot of places mention using camera effects/shaders to make it so the furthest point in the scene is hazy to the camera. I understand the concept... I just can't find a place that guides you through the process...

[Corey Beaulieu]

Maybe you are just looking for a ZDepth pass:

 

http://www.ronenbekerman.com/adding-fog-using-vrayzdepth-render-pass/

 

or even just turning on environment fog and use a VRay plane. Did you say what render engine you are using?

[andrewrpreza]

Maybe you are just looking for a ZDepth pass:

 

http://www.ronenbekerman.com/adding-fog-using-vrayzdepth-render-pass/

 

or even just turning on environment fog and use a VRay plane. Did you say what render engine you are using?

 

Sorry I forgot to mention, I'm using Mental Ray.

 

 

 

Not sure if that example is what applies to my case...

 

Let me put an example:

 

Imagine you are in a helicopter, filming a couple of high tower buildings below.... What method would you use so you could not see the artificial end of the world space?

 

I've seen a lot of people avoid the problem all together and just go with the unrealistic way of having a square piece of land just floating in space. Then they apply a cartoon/sketch shader and thats how they justify it. I actually really really hate that.

 

 

Thanks for your replies btw!

[Corey Beaulieu]

This will be my last suggestion as I don't know mental ray well enough to truly be of help, but if you turn on Horizon in your camera you'll get a line in your scene that represents this contact. As long as what you've build covers this line it will never matter and then the ZDepth pass will work to create a haze at a distance.

 

Without and endless plane like VRay has, and it seems that trying to build an enormous plane in Mental Ray creates GI issue at render time, I think you won't be able to do this correctly. The sphere with inverted normals is the trick to truncate the world space extends, but you mentioned trying to avoid this.

 

Good luck, I hope it works out in the end.