KludgeCity v2.5… a plan for the future
I’ve started designing the new overall feature-set for Kludge, based on the last year’s worth of experimentation. The purpose moving forward is to create a leaner, more robust, more useful tool in my production context.
So first, to trim the fat:
- I’m removing all interior geometry. I’ve never been happy with the way it worked, and I stumbled on a new approach to window rendering that I’m excited to try out.
- No more balconies. They never looked very realistic, and I’m considering a non-procedural approach to these kinds of facade details
- I’m reducing the number of window options — my production focus now is on creating buildings that would feel comfortable in the 1940s, before the modern skyscraper’s glass-sheet style. I may revisit this, but for now, focus on style is more important.
- Fewer custom options — In v2.5, almost everything will be based on ratios instead of absolute values. The Randomizer will become the main value controller, and every building will be randomized to some degree. Sorry folks, no presets.
- The new KludgeCity will use ONLY two shaders across all buildings… one for windows, and one for the building itself. All other variation will be handled through some other means. I’m working on this now, and I have some promising leads.
- per-face shading is out. Windows and the building’s body will be seperate polygonal objects. This can cause problems such as light bleed, but after a discovering a whole sh*tstorm of issues with component shading, this is a necessary evil.
- the UV variation grid is being reduced to 5*5 — 25 variations of textures and light intensity is more than enough.
- for now, I’m removing the “base floor” layer, until I can come up with a better method.
- KludgeCity will now NEVER provide UVs to anything but the windows — UVing complex geometry with MEL is beyond my ability — after three years of trying, I’ve decided this. However, I will be working on a robust 3d procedural shader that I can use instead.
So, now I’ve figured out what I want to trim down, next, to figure out what I want to add…
Where I’ve been
Kludgecity has always been a production-driven script — meaning, I started making it because I had a real use for it, and it was easier to make a versatile tool than to model out a city by hand. Then, the style and requirements for my short film changed, so I had to start the script over from scratch. So what happens when I abandon my short film for over a year? Well, I just don’t have any real incentive to keep working. But there is good news! I’m restarting the effort soon, and along with it, I’ll be finishing up Kludge as a production tool. Hopefully in July we’ll start seeing updates again!
UV madness
The current version of Kludge uses a procedure I call “unitizeAndPlace” which divides up the window UVs into an 8×8 grid on the 0-1 UV space. It does this by iterating through all selected faces and assigning them to randomly-selected spots.
This is very slow. On a building with ten thousand windows, the uAP script has to run a loop to select the face, pick a random number, and move the UV shell ten thousand times. Usually this takes a few minutes, but the larger the number of faces, the larger the performance hit. A massive building with 60,000 windows will take more than an hour to UV.
The result of all this is that 1/64th of all the faces end up on each of the 64 possible UV grid spaces — which means there is a much better way to do this. Instead of randomly placing 10,000 faces, instead, I’m now creating 64 groups of random faces and assigning them to each of the 64 spaces. The randomization and selection process still takes some time, but I’m also using sets instead of arrays for the face lists, which should reduce the amount of time required writing and re-writing arrays.
I’ll post up the results whenever I run some stress tests. I think this script could be useful for a variety of projects, not just Kludge.
Version 2.0 Delayed… again…
I’ve recently started a job with a studio here in Dallas, so I haven’t been able to do ANYTHING with Kludge for a couple of months. I still need to fix a handful of hiccups with Maya 2010 not working correctly, but more importantly, I’ve actually come up with a few really good ideas that I want to incorporate before I release version 2. I appreciate everyone’s patience… the end result should be a streamlined, production-friendly tool that actually works as advertised. In the meantime, check out the progress on http://sumofparts.wordpress.com — the short film that Kludge is ostensibly built for. We’re actually making assets! hooray!
By the way, if any of you are using Kludge to do anything interesting, send me a picture!
A note on process
In case anyone’s curious, I thought I’d let you know sort of what my process is when I’m working on Kludge.
Most importantly, I keep my eyes open when I’m out and about. I live in Dallas, so we’ve got a fairly decent variety in our skyline. I take photos when I can, and look at pictures of interesting buildings online. There is sort of a vocabulary of city architecture — some buildings have alternating stripes of material (what I call “buffers” in the script), some buildings have windows that wrap around, some have blank walls without windows, some are monolithic and flat on their facades, and others have all kinds of details extruding out from their surfaces. My job is to take those basic architectural ideas, and make a system that is capable of creating them on the fly, for any mixture of features.
It doesn’t always work.
The first step is always to model out the structure by hand. Everything you do in Maya has a corresponding command in MEL. In theory, if you can do it manually, you can do it in a script. I’ll work out a list of steps that are involved in creating a particular bit of geometry, and write out a sort of “pseudo-code” that summarizes the process. Then I figure out what MEL commands will give me the desired result. Usually this involves a lot of guess-and-check and many trips to the technical documentation. MEL is good at a lot of things, but it can be incredibly difficult to find a scripted solution that mimics human creative judgment. “select the faces that are facing outward from the building” is great if you’re talking to a modeler, but translating that into code can be tricky.
At the core of Kludge there is the default building — the only building that is guaranteed to work perfectly every time. Whenever I add a new feature, I work with this default building at default settings until I make it work correctly. The “ideal test case” is something I come back to throughout the testing process — every time I make a major change, the first thing I check is to see whether the default setup still works as expected.
After that, I try out a handful of other configurations. If all goes well, then I proceed to do everything I can to break the system. Most of the time, this is not difficult. Usually, I try to “user-proof” the system to the best of my imagination, but the truth is, there are more ways to break Kludge than there is time for me to fix them. All I can really do is try to make the system as flexible as possible.
A lot of the functionality of Kludge will eventually involve randomization, and I really can’t ensure that every combination of features will look good, or even work at all. But I guess that’s really the power of working procedurally — if you don’t like the result, in a couple minutes, you can have an entirely different building. There’s no reason not to try a bunch of different things and only keep what works.
Ed Whetstone's Kludge City 