You Can Never Have Too Many Greenhouses

The 3D model of the Prisoner of Azkaban castle keeps chugging along! After completing that first greenhouse, I duplicated it three more times:

These four all share the exact same design, but then there are four more along the east side of the Durham area, and their dimensions are a little different, so I had to create (and thrice duplicate) a new variation over there:

And then at last there is Greenhouse Three, which is a smaller lean-to on the castle’s outer wall. (You can catch a glimpse of it in the above render.) This is the greenhouse where the Herbology lesson with the mandrakes takes place. It’s got its own unique design, so I took care of that next. Some of the dimensions here don’t line up quite as precisely as I’d like, but I’ve tried to minimize the number (and visibility) of compromises as much as I can:

You can also see that I’ve also added rust, adjusted the weathering of the wood, and started with the footpaths between the greenhouses. I even threw in one of the largest vines that snakes its way out of the greenhouses, visible toward the bottom right:

In the background, you’ll see that I’ve begun the curtain walls around the greenhouse area. These were actually there in the original design of the castle, even before the greenhouses were added in Chamber of Secrets; they just had to be pushed outward a bit to accommodate that addition. Here’s a better view of their progress:

See where the wall stops on the right? That’s going to be the site of the final greenhouse structure, the domed conservatory that also acts as the only way out of the greenhouse courtyard and into the grounds. But I’m going to save that for the next post. I’m hoping to even share something I’ve never seen before: an interior view of that conservatory*!

In the meantime, I’ll leave you with a slightly different aerial view of the POA model so far. Still plenty more to be done, but we’re getting closer!

* If they happened to include the conservatory interior in any of the video games, let me know! I haven’t played them but I’ve looked through longplays on YouTube and never spotted it.

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!

More POA Hogwarts Texturing

Well, so much for turning the materials off and focusing on the modeling again! The process of creating and tweaking and refining these textures has become a bit addictive.

Here I’ve created a shingle texture for the roofs and spires. The finials have also received a copper patina treatment to match what we see in the films. (Again, no image textures here – all procedural.) Less obvious are some subtle adjustments to the brick texture. Notice how the bricks no longer appear to be all perfectly flush with each other – some stick out slightly further, like you’d see in real medieval construction. There were still more tweaks needed, though. In particular, I wanted more vertical streaks to mimic dirt deposits from years of rain and weather. Those are quite noticeable on the “real thing.” Many hours later…

…that’s more like it! Still not perfect, but I don’t think I’ll be able to convince current versions of Blender to do any more on their own. I could paint the streaks in myself, but I’m still really trying to stay procedural so that when I build the rest of the castle, the brickwork and weathering and dirt patterns will all just magically appear without any further work. (Unrelated, but you can also see a few contour lines down near the shoreline. Once these are completed, they’ll act as a guide for me to sculpt the landscape the castle sits on.)

If it’s been a while since you’ve seen the first couple of Harry Potter films, you might be thinking that this castle looks awful colorful. Were the bricks really that red, the roofs really that bluish? Well…yes, at first. The Hogwarts we see in Sorcerer’s Stone and Chamber of Secrets has pretty saturated colors. Here’s a frame from the latter, for instance:

It was really only once we got to Prisoner of Azkaban that the colors took a turn for the grayish green. At least part of it was just color grading on the film; it’s hard to tell if the miniature itself received a cooler paint job, but if it did, it wasn’t as dramatic a difference as it appears in the film:

That’s more or less the color scheme we see through the rest of the series, and the theme park versions at the various Universal resorts don’t stray far from this look. So despite my original intention to just get the original look of the model, I created an alternate coloration for the model, too:

It’s still not as green as what we often see after the first couple films, but it’s at least closer. I set up the material nodes in Blender so I can quickly switch between color schemes across the whole model; I suppose I’ll probably stick with this coloration while I continue work on the POA version, but the more colorful version will be ready to go when I start working on the castles of the first two films.

I’ll round out this post with kind of a cool, different shot of the castle in silhouette. You can see I’ve finished the windows on the Defense Against the Dark Arts tower, although I discovered a small mistake in the lowest row of windows after this render was made. Unfortunately, this angle also highlights some of the areas where the bricks don’t map quite right onto the forms of the castle. After a lot of experimenting, I’m starting to think this may be as good as the mapping is going to get. But who knows?

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.