North Shore – Days 11, 12, 13

One often overlooked feature of really immersive FS scenery is detailed groundwork. Flight Simulator has two methods for displaying the ground natively; either through the terrain tiles (or custom photoscenery tiles as in this case), or the stock hard surfaces that you find in default airports. Though the resolution of the terrain tiles has improved markedly in FSX, even the highest resolution ground using this technique looks blurry and indistinct from ground level. That’s fine for grass or dirt, but with hard surfaces such as asphalt or concrete, it isn’t very convincing. On the other hand, the stock hard surfaces such as default runways and taxiways are razor sharp. They use repeating textures scaled down to the point where they deliver detail, but at the expense of easily recognized patterns and a generic sameness to their look.

What I wanted for Plum Island airport was to get as close as I could to the real grass and asphalt environment, which includes cracked and broken pavement that’s been heavily patched. To get there, I had to do a couple of things.

The photoscenery for all of Plum Island and Newburyport was downsampled to 1m/pixel for the sake of file size. Even at that resolution, the terrain for the area takes up a healthy 125mb or so, and at the original 50cm/px resolution of the images, it’d be more like four times that. Now, 1m/px looks fine from even a few hundred feet up, but it starts to get fuzzy at ground level. Here’s what the groundwork on the airport looked like at that res:

Stock 2b2 photoscenery at 1m/px

Stock 2b2 photoscenery at 1m/px

Since virtual pilots are more likely to be on or near the ground at the airport, I’d like to make the ground there a bit more distinct. Using my original 50cm/px imagery, I made another patch of terrain for just the airport that overlays the overall photo. Doubling the resolution (and darkening/greening the grass) has this effect:

Airport with 50cm/pixel terrain overlay

Airport with 50cm/pixel terrain overlay

Okay, better. As far as the grass goes, that’s convincing enough even while sitting on the ground. But what of the asphalt? You can probably see from the shot, even at 50cm, it’s blurry. This is where it gets dicey, as I had to rely on FS8 technology to get the resolution I needed on the ground. I made a polygon containing repeating asphalt detail textures, much like the stock aprons. Then I added layers of cracks, stains, and patches. This is something you cannot do using stock methods for FSX. The result is this:

Apron ground poly with texture, cracks, and stains

Apron ground poly with texture, cracks, and stains

It’s starting to look a lot more like the real Plum Island now. Still, it’s not that much more convincing than the stock asphalt, except for the cracks and stains. This is where the final magical layer gets added. Using the aerial photo of the airport, I enlarged the apron section to 1024 x 1024 pixels. Yes, making a smaller image larger did soften it some. However, what I’m after isn’t sharp detail – I have that with my base detail and crack textures – what I want now is to simulate the changes in the color of the pavement that gives it that worn, patched look. I made a top ground poly layer consisting of this aerial photo, with partial transparency so you can see the detailing layers below it. When added, the airport really starts to look alive.

Ground poly with aerial translucent overlay

Ground poly with aerial translucent overlay

Check this out: here’s a shot I took at the real airport, side by side with one from the sim scenery in its current state.

real vs. FSX with custom ground

Comparison: real vs. FSX with custom ground

It took me three days and a couple of new techniques to get the ground to this point, but I think it’s worth it. Seeing these two shots side-by-side, I see things I still want to tweak. Will this madness never end?

Advertisements

3 responses to “North Shore – Days 11, 12, 13

  1. Wow! Looks great. Would be very nice with a more in-depth explanation of the techniques used as I have been trying to do this myself. Thanks!

  2. I’m working on an article for SimPilotNet.com that explains this technique, Marcus. Well, I will be once I release the scenery.

  3. Thanks a lot! I’m definitely keeping my eye on this.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s