Better together: Making sense of the frenetic floating fleets in Flock

Cosmets. Bewls. Pipers. Gleebs. These aren't the mutterings of a lunatic, but rather a mere handful of creatures you'll be able to charm and collect in Flock, the next title from Wilmot's Warehouse and I Am Dead developer Hollow Ponds.

Flock is a chill adventure about exploring a wondrous world atop a giant bird (or maybe you're just very small?). On your travels, you'll have the chance to discover and nurture a flock of creatures that will trail in your wake, swirling and chirping in all the colors of the rainbow.

Last year, we spoke with the dev team to learn how they designed Flock's naturalistic world. Now, to commemorate the title launching on July 16 (wait—that's today!), we caught up with Flock creative director Ricky Haggett and programmer Mike Robinson to find out how the team implemented Flock's, well, flocks.

We'll all float on

Haggett explains camera positioning was key to cultivating a certain feng shui. When players are careening across glades and weaving between ferns like a sentient Concorde, the flock will drop backwards so it doesn't obstruct the camera's line of sight. When they're engaging in more serene activities, such as attempting to woo another critter into their menagerie, they'll congregate nearby without a care in the world.

"Early on, there was definitely a thing where the camera was always in amongst the flock," he says. "It felt cool but also broke that feeling of zipping around. I think we have a sweet spot now where you still get these nice moments of being amongst them, but only for a fleeting moment before they drop back."

Robinson notes flocks generally follow a few key rules that determine how they congeal. He says each gaggle of creatures follows a spline that trails the player-controlled bird. When they stop, that spline "meanders off" and creates a metaphorical holding pen before latching back onto players when they decide it's time to hit the proverbial gas. The code and logic that determines how creatures position themselves was designed to ensure performance wouldn't be "too much of a worry."

He notes it all started by implementing a point cloud of base positions that was stretched out around the spline trailing the bird. "The beasts aren't really aware of what's going on and what's nearby, but then we do things like when you're flying close to stuff that can contract in, or when you swing out and do a big curve, the points that are travelling past that curve get pushed to the side slightly," he continues.

"None of the creatures are aware of the speeds they're travelling at or any of that other stuff. It's just kind of mapping them to this spline than pushing them out based on the extremities of curves and other values."

As players explore the world of Flock, they'll be able to unearth new creatures and win their affections—hopefully convincing them to join their giddy gaggle of gliders. That collect-em-up mechanic required Hollow Ponds to not just consider how each flock should move, but how new creatures should slot into established herds.

"At the moment, [newer] creatures will travel to the front," says Robinson. "Some of the key creatures will want to head to the front of the flock to get more exposure. But we also ended up going through and checking all the sizes of each beast in the flock, and we asked whether it was worth ensuring each [creature type] had specific area?"

The trouble with flying sausages

The answer was 'no.' The team felt positioning had already reached a "nice point" that didn't demand an extra layer of complexity on top. Haggett acknowledges that creatures (which come in all shapes and sizes) can still sometimes clip into each other, but the nature of player movement means it goes largely unnoticed. In fact, the biggest challenge Hollow Ponds encountered when fine-tuning flocks was sorting out the long bois (not their official name).

"Most of the creatures bend using material stuff," says Robinson. "It's just a fairly cheap material solution that doesn't involve updating skeletons. Haggett quickly chips in here to explain bending largely involved moving the vertices at render time based on curve values. The issue is that solution looked awful when applied to the longer, more sausage-like creatures.

"We ended up using the spline mesh tech, and then bolting on a skeletal mesh for the head at the front [of longer creatures]," says Robinson. "It was about making sure those curves come out nice and mapped to where you want them to be, basically. It's just a two-point spline, and we didn't want to split them into multiples because that could be a higher CPU cost."

Flock concept art showing an array of creatures

Initially, those longer creatures—which are actually called Pipers—had separate head meshes and two or three body meshes. Robinson, however, put a lot of work into mapping a two-point spline to ensure pipers only needed one body mesh. "I just put a lot of time into working out how to map this two-point spline so I could get it to travel through four points by adjusting the tangents," he adds.

Haggett says that was a pretty big win because it's not "phenomenally expensive" in terms of performance. "You could make a skeleton with a bunch of points, and then you can deform the mesh around that skeleton. But that's so expensive—especially if you imagine the nature of this game," he continues.

"You can have 30 of those things [flocking around you]. You can have four players, and so then you can have 120 of those things all flying around together on a low spec console. It's just not going to work."

Preventing players from welcoming more than 30 creatures into their flock was partly in service of stability, but Haggett says it was also something of a goldilocks number that looked *just right* on-screen. "There was an optimization thing happening, but as you start playing the game for real and start collecting things and putting them in a flock, there's a meaningful number of things you can put in your flock and actually care about," he says.

"It's your shelf of cool stuff, is what your flock is—and there's a reason why as you make that number bigger it doesn't necessarily feel better. Also, just visually, the feeling of flying around with 30 creatures wasn't that different to the feeling of flying around with 50 creatures. Weirdly, especially as we finessed the variety of creatures and started having lots of different sizes and colors, you get the impression of a big flock of creatures with 30."

Part of the magic of making games, of course, is having the ability to experiment in ways that players never will. So, just to see how far he could push the boundaries of flocking, Haggett did some tinkering to see how a flock of 3,000 creatures might manifest. The result, as shown below, is beautiful, boisterous, bedlam.