Night Falls on Hogwarts

I liked that fire material from the last post so much that I kept finding myself virtually lighting the torches and switching to that day-for-night setup. Eventually, I got wise and decided to create a dedicated “night mode” for the model. It has a different HDRI for the background (a cloudy daytime scene from HDRIhaven.com that I made much darker and bluer), stylized blue lighting to match the moonlit shots in the first couple films, and interior lights behind some of the windows. Compare:

Best of all, I realized I could use Blender’s node group functionality to create a single slider that would allow me to change all the different settings between day and night simultaneously. I also did the same for the two color modes (the warmer look of the first two films, and the desaturated look of the later films, seen above).

Both tasks were made easier by some behind-the-scenes organizing I’d been doing. The procedural (algorithmic) brick texture on all the walls had gotten really complicated, because I was layering so many different elements together in the pursuit of a realistic and visually pleasing result. For kicks, I thought I’d share what the brick material’s node tree looked like before:

Each of those little gray boxes (nodes) is a set of calculations, receiving inputs and sending outputs via those light gray lines that connect them to other nodes. I’d organized them into those colorful groups, each of which has a descriptive label, but it was still a pretty ugly setup and not that easy to use or “read.” Here’s the same material after visually organizing the node tree a little better:

Not only does this look cooler, but it’s a lot easier for me to just jump in and make changes or additions where needed. (Which I’ve already done repeatedly since taking that screenshot…the setup is even more complicated now, but still nicely organized.)

You might have noticed that long wall at the bottom right of day/night renders, connected to a small tower. These new additions will barely be seen in the final version of the POA model – they were part of the original model from the first film, but starting in Azkaban, the landscape became much hillier and it literally swallowed up most of the wall and the entirety of that tower. But I decided to build the whole thing now so that it would be easier to create the versions for the first two films when the time comes. Here’s another shot:

There’s also some work happening here on that wall beneath the hospital wing bridge, just to the right of Gryffindor Tower in this image. Here, let’s take a closer look with the clock tower and hospital wing temporarily hidden, and some improved texturing on the roofs and spires:

Windows, dormers, drainpipes, corbels, the whole nine yards. That wall is done now, and you can even see some work happening on the tower on the right. Fast-forward a bit, and here’s a closeup of that tower, now complete as well:

Some of this geometry was definitely tricky to get right, but it was worth it in the end. I also had a lot of fun with the decorative elements near the top – there’s a triquetra near the top of each dormer, plus some sort of decorative plaque just below. I couldn’t quite figure out what is embossed in the plaque, so I just sculpted something that looked similar and baked it as a normal map. [EDIT 4/24/19: I finally found a clear enough photo of the plaque – it’s the Hufflepuff crest! Guess I’ll have to go in and redo it at some point…] You can also see the new diamond-shaped muntins in the windows, which are now in all the windows of the castle so far. (I admit that I didn’t go procedural with these…I briefly tried, but it just seemed more efficient to use a single diamond image that I could tile all over the glass.)

Taking a closer look, though, the roof shingles aren’t supposed to get flattened out in some places like that. Always more to be done!

The Defense Against the Dark (3D) Arts Tower – Plus the Textures of Hogwarts

Work continues on the Prisoner of Azkaban version of the castle. My tentative plan at this point is to more or less finish this iteration before fully jumping to any of the other films…but I’ve been known to jump around, so who knows.

The latest structure to take shape is one that other Potter fans seem to refer to as the Defense Against the Dark Arts tower. Apparently the video games place the DADA classroom in this tower, so the community rolled with it. Anyway, this was first seen in Sorcerer’s Stone, and it stuck around through Order of the Phoenix,with a slight relocation from Azkaban onward. (After that, it was replaced by the Astronomy tower, which is basically just a taller and more extravagant repurposing/redesign of the DADA tower.)

There he is, just to the left of the Dark Tower. Basic shape starting to form.

As I continued to work on the top part of the tower, I realized that the DADA->Astronomy transformation (transfiguration?) actually “revealed” some parts of the DADA tower that weren’t visible before. Presumably, these were designed specifically for Astronomy, but I figured it’d be more efficient for me to just create them from the start and conceal them with the remaining DADA structures; then they’ll be ready to go when it comes time to do Half-Blood Prince. Below you can see the Astronomy-ish version on the left, and then on the right we see one of the turrets that conceal some of the geometry on the DADA version.

Then I started adding a few more details on the top part of the tower, resulting in the following render:

…which I liked, but I was starting to get fed up with my plain blue placeholder for the lake surface below. I knew I didn’t want to spend time creating (and rendering) full-on water shaders, but I thought it would at least be cool to try to create some atmospheric perspective (mist) along the horizon. In the process of working that out, I started running into some ways to break up the surface of the water a bit, too, and I couldn’t help myself. Soon enough…

That felt like a good step in the right direction, but it wasn’t enough. I kept going and eventually ended up with this shot, which I gotta admit, I really like.

The reflective water shader has some procedural variation in the roughness to simulate areas with more or less wind. There aren’t any actual waves, though…if I ever decide I need to get in close, it’ll need more work. Then there’s some volumetric fog along the horizon. (It’s literally just a huge torus with some cloudy volumetric shaders on it; I distorted it and put it way out in the distance to help blend the edges of the water with the HDRI background.) I love how my fog blends right in with the photographic clouds just above, particularly from this angle.

Now I was in full-on texturing mode. If I were a wiser man, I’d save all this for after I finish modeling…but where’s the fun in that? I decided I wanted to start experimenting with textures for the castle itself, too. And I decided I wanted to go all procedural.

I mentioned that word before, “procedural.” I’m inevitably going to use more CGI lingo in these posts than I have time to explain for those of you who don’t do 3D art, but this one is worth delving into for just a sec. Basically, anytime you apply a texture to a computer-generated object, the two most common ways to do it are to apply images to the surface or to work procedurally. A procedural texture is one that doesn’t involve any images – instead, you’re telling the computer how to mathematically generate the imagery based on the surfaces it encounters. There are many pros and cons to each, and they each have a lot of uses. One of the pros to going procedural is that if you set it up right, it’ll conform to stuff you build in the future, too. And of course, I still have a lot to build.

Anyway, bottom line, I’m trying to completely avoid using pixel-based images in this main castle texture. After fiddling with dozens of nodes, I came up with this:

We’re starting to get there. It’s beginning to have that stony, bricky, castley look. These color patterns were starting to work for me, but the nodes weren’t behaving quite the way I expected with regards to the way light reflects off the surface (specular, roughness, and normals). I found the problem, did more tweaking, and arrived at this improved version:

The difference is fairly subtle, but to my eye, this looks a lot more realistic and lot more accurate to the films. (Of course, getting a single texture that fits the look of all the films would be impossible, since the color grading changed so much after the first couple of films, making everything kind of greenish-gray. I’m trying to just match the physical miniature as best I can.)

Still, this is very much a work in progress, and it probably won’t be too long before I turn the textures off and just focus on modeling some more.