For this week's interview we have the pleasure of talking to one of the truly great names of ZBrush: Martin Krol. Not only has he been using the software for a very long time, but he has been a key beta tester as we've worked to expand the limits of what CG can do. Now that "Underworld 3: Rise of the Lycans" is out on DVD, we thought that this would be a great time to catch up with Martin and get him to talk. (No waterboarding was used in the process of this interview.)
Let's begin by talking about you. Where you're from and personal background.
I was born in Warsaw, Poland. I found drawing very early on and while I wasn't all that good at it, my mom was nice enough to be honest and tell me that I was going about drawing all wrong. She had just given me a few words of advice, that I should really look at what it is that I am drawing and think about what I am putting down on paper. Up until that point I never gave it any thought, and I was mindlessly drawing stick figures. I loved to draw. It was immediate. I could experiment as much as I wanted and I could quickly explain thoughts visually. Of course receiving validation by my teachers and people around definitely made me more aware that art was something I wanted to keep doing. It almost felt like being a musician on stage and having the crowd applaud at the end of the performance, except at a smaller scale. At the age of 6 my parents decided to leave Poland and live in Italy. They weren't entirely keen on living in a communist country, so we left and Italy took us in. After a few years of living in Italy we were told we would have to go back or move elsewhere, so the decision was made to go to Canada. Within 4 years of living there we got our citizenship and have been living "happily ever after". (Chuckles) I am still unsure how or if all of the experiences gathered throughout that time helped me in the long run, but at least it opened me up to diversity.
Somewhere around the early 1990's my parents had taken me to a number of films like "Terminator 2" and "Jurassic Park" and with seeing what was possible (including TV shows like "Reboot") I thought that the digital arts would be the next step that I would take. However, I would have to wait until the age of 17 before I had my own computer that I could learn on. It's all good though because it gave me a lot of time to practice drawing, and work on my hand eye coordination.
How about your professional background?
The closest comparison I could make would be that the beginning of my professional background was similar to my childhood. A little bit of moving around, changing jobs, and the feeling of walking uphill the entire time. The first exposure I had of working in this industry was when I did co-operative education. I had my first dose of reality when I tried landing an interning spot at a CG shop.
With the help of my teachers, I had found a list of about 40 shops of all types in and around Toronto. I was ecstatic at what the future would hold and all the possibilities. After a few hours of calling all 40, it wasn't until the very last one that I got some sort of response other than "sorry we don't work with high school students". I had my interview with the owner of the company (I feel bad for not remembering the studio and the owners name), but unfortunately he couldn't afford to keep me there as he would have needed to purchase another license of Houdini. At the time Houdini used to cost around $17,000. There were no cheaper versions, and no demos to speak of. Instead, he set me up with two interviews with his pals, one at SideFX, and another at Bee Vision. It didn't work out at SideFX, but I finally managed to land a spot at Bee Vision. Over at that shop, I got my first hands-on with the Maya software. At the time I think version 2.5 had just been released and luckily, I had a HUGE set of manuals to learn from. It was absolutely daunting.
I was with the shop for the entirety of the course (which went from February until June). I got asked if I wanted to come back after I had finished school, but I turned it down because I had the intention of continuing my education at Sheridan College. The animation program at Sheridan was second to none at the time. A great many graduates made their way into prestigious studious, so it only made sense that I would want to go where success could be found. I applied to other schools as well and I got accepted into every single one except my number one. (Man, that rhymes!) After having thought about it for a while and the possibility of going elsewhere -- considering how all the other schools focused on general "multi-media" (which was all the rage back then) and not on fine arts or classical animation or even any sort of 3D -- I made the decision to skip out on school entirely and teach myself. So I got myself a GeForce card, some software demos and learned as much as I could within the time that the software worked. Around this time I had gotten access to Mirai. After using the demo for a little over half a month and posting my work on the forums, I landed a job for a research project headed by the guys at AT&T in New Jersey. Two years later I landed a gig at a startup wannabe-Pixar shop in Italy and it was around this time that I was finally able to do what was closely related to what I had wanted to do since the age of 10.
Since then I've worked for a few shops, one of which is Technicolor | Vfx, and the others being Pseudo Interactive, Intelligent Creatures, and Rune Entertainment.
Fun fact: It was my ZBrush 2.0 demo that I made WAY back in the day that got the guys at Technicolor interested in hiring me! In fact, thinking about it now it was my knowledge of ZBrush that has gotten me every gig I've had the pleasure of participating in so far.
What are some of your favorite projects that you've worked on?
I've worked on quite a few projects but the most rewarding up until now have been the environment jobs. The projects I am talking about are "The Legend of the Black Scorpion" and "Underworld 3: Rise of the Lycans". "The Banquet" was a really enjoyable project to work on because we didn't have a super tight deadline. The project involved creating a huge palace, a scorpion, an army of little soldiers, horses, weapons -- you name it. It was like a mini Chinese "Lord of the Rings". The other thing that made this project enjoyable was that my supervisor (Brent George) gave me a ton of freedom and he gave me the chance to lead the asset creation for that entire project. This project also allowed me to learn a lot more of Houdini with the help of Gene Dreitser.
"Underworld 3" was a much different project. It was very similar to the way we went about creating the palace for Banquet, but the software that glued the project together was different, the entire focus was on the environment, the deadline was super tight, and it was a lot more organic than the Chinese palace. It also allowed me to use ZBrush for something other than characters, which is always a nice change of pace.
Not to say that I don't enjoy character work, because I absolutely love it but I just love diversity in work. Being pigeon-holed to just character work would bore the lights out of me. Unfortunately for Toronto, there is almost no high rez character work to be had.
What were your title and job description with Intelligent Creatures? Without being too specific yet, what did you do for Underworld 3?
At Intelligent creatures my position was as a regular modeller. It was a nice break from having a lead position like I've previousy held because I didn't have to micro manage all the modellers involved and keep track of what they were working on. I could focus my energy on creation. This was a good thing because in the end there were a lot of elements to keep track of for which I was responsible anyway. When I first started I was going to be purely modeling the assets, and later we were going to figure out how to do the rocks. The modelling team consisted of a few people, but Chris Zammit and Chris Yoo are the only Modellers names I remember off the top of my head at the moment. Because I went ahead and mocked up some rocks early on, my supervisor (Josh Clark) thought it would make sense for me to take the responsibility of creating the rocks and cliffs for the project. Anything that looked organic was essentially mine. Being that at the time we didn't know if anyone else could use ZBrush, he handed all the ZBrush-related work over my way. One thing I didn't have my hand in at all that the other modellers did was on the texturing process. I was entirely hands-off. If I remember correctly, the texturing process and management was handled by Chris Zammit and Josh Clark.
What was your favorite contribution to this film?
I think my favorite contribution was when I got to model the Gargoyles. It was very much open to interpretation below the chest area because that part was never created on the set. It allowed me to do some pseudo character stuff, wrapped up in the form of a statue, sculpted out of the same rock as the rest of the fortress was made out of. I didn't have a lot of time allocated to the gargoyles so they aren't refined as far as I would have liked but I like the overall design. Though I much prefer the concept we received for it, as the faces looked cooler than what I had to use. (Which were the references from on set.) Plus, it almost feels like it could have gone on a heavy metal CD cover.
What is your workflow for creating environments? How does it differ from creatures?
That is hard to answer, because I use the same techniques and tools for both, but I generally keep work in a way where I save OBJ's out of Modo early on (with UV's) and work within ZBrush. If I need to change UV's, I load up the same original file that I used to export from the first time around. I never go back and forth because point order can be lost and such. I always keep the original file in Modo, make changes there, and export out to ZBrush with any changes that I might need like UV's, or new geometry.
With environments you don't have to worry about seams as much, unless you have parts that are split up into multiple objects so they can receive more texture space. On Underworld we found that we needed to split up the canyon/cliff rock face into about 14 pieces. Having the Clay and Flatten brushes helped immensely as I could use the Clay brush on seams to bring geometry to the front and fill in any gaps, then Flatten them out to hide the seams.
The other big difference is that for environments I find myself having an easier time retopologizing because there is no reason to be anal about topology.
What are the major challenges that you encountered with this project? How did you overcome them?
I think the biggest challenge on "Underworld 3" came toward the end of the project when we found that we needed a lot more texture resolution for the rocks. Originally we had only 3 pieces to the cliff, but as we started to make test renders (which started too late in my opinion) it became very clear that we would need a lot more frequency in the displacements. The first thing I did was split it up into more pieces. This made things more difficult for me because now I had many more displacement maps to deal with, many more objects to blend between, and I couldn't load all of them at one time due to hardware/software limitations. To make things easier for the guys and myself, I was using 32-bit displacement maps. Granted, they took up more space but it allowed us to avoid having new values to adapt each time I made changes to the models. The models were holding up much better than before during close ups, but for the main shot where we were right up against the cliff it just wasn't enough. What we ended up doing is a combination of a few things. One was to create smaller chunks that could be reused and redistributed along the cliff sides. The main issue with this is that it would be hard to implement on a rather flat rock face that has no layering to speak of, so this was mostly used on the front center face due to it being broken down by the buildings. It was just easier to fit smaller chunks between architectural pieces. The other thing I ended up creating was a somewhat tiled displacement map. This way, if we needed any extra frequency in the displacement, we would use the main displacement map for the forms and then for the smaller details we just used a tiled map.
Intelligent Creatures contributed 86 shots to the film. How many of those did you work on? About how much time did you get to spend on each element?
The only shots we had (as far as I know) were environment shots. Anything with the fortress in it, or the cliff. So technically I have a lot of shots to choose from when I cut my reel. (Grins) The amount of time we had for each element varied. Generally we were given about 1-2 days per element, while trying to create several resolutions for each. I am unsure if the different resolutions were used in the end, but we had a few near the beginning to mid-production.
The cliff went through a number of redesigns while I was already sculpting, so there was a bit of frustration on my part because I had to zig zag a lot. At the end I remember having an absolutely insane day where I had to go over the entire mountain, split it into 14+ pieces, re-UV the whole thing, re-project all of that data onto each piece, and then having to clean up the seams with the Clay and Flatten brushes. Due to needing the highest amount of data possible, the models weren't light on resources either. Which meant I also had to track down each combination of files that I had to seam up against, delete the surrounding models and then create a displacement map. Otherwise I would get a crash due to running low on RAM. The hardest crunch I had was an hour or two before the deadline that I was given, when I found that the UV's were corrupt on the new files. Let's just say it wasn't a whole lot of fun, but I had to redo a lot of the work that I had done over the entire night. Luckily I had saved each combination of files, and I didn't have to worry about seams this time around. With a bunch of clever reconstruction and reverse engineering it all worked out just fine and I made the delivery.
The way this project worked for us was that Intelligent Creatures would create the environment and then send the rendered shots off to Luma to integrate their creatures into.
How did you utilize ZBrush in this project?
In the way it's meant to be used! High resolution sculpting. I didn't use it for any texturing. I used Clay3d for retopologizing because it is a bit more flexible in that aspect due to how its main strength is in building meshes, so I exploited that strength. In ZBrush, "Project All" came to the rescue many, many times -- especially toward the end -- including the gargoyles which were built from several meshes. I used "Project All" to compare the several meshes that the Gargoyles model was made from and the final mesh which is just one retopologized piece. Alphas were heavily used to quickly add the initial random rock formations. I used a combination of some textures converted into displacement maps, as well as handmade alphas. Once the initial form stage was done, I used the Flatten brush with a touch of the brush mod setting on the positive side. This allowed me to further "extrude" parts of the rock and create flat faces. (Make sure that the falloff of the brush is harsh, and the alpha set to square/none.) This gave me the crisp edge I was looking for. From there it's just a matter of refining, pushing outward and inward, while defining the main planes of the rocks. Once you have the planes defined and some crisp edges, it's good to use a Flatten brush set slightly to negative, with an alpha. This is useful for cutting some sharper detail into the otherwise smooth rock formations.
What would you say is the trick to creating environments that are utterly fantastic like the fortress in Underworld, while still keeping it believable?
It is a matter of a lot of things playing well together. The landscape has to have weight to it first and foremost. Structures should have some resemblance to realistic creations, and should also be designed in a way that allows for weight distribution along the proper channels. As long as it looks like it could exist in the real world then it "should" be OK. Having a lot of detail where it is needed helps a lot as well. Rocks generally have a lot of flat planes, as well as a lot of detailed areas with sharp edges. Maintaining that sense of detail, balance, and weight is enough work on its own. Nobody really gives you a blueprint to work from when you work on mountains. All you get generally is a base form to start from, or a vague plan, but the forms and look of the rocks is usually up to the artist to explore. Lighting and shading has to be solid as well. One of the challenges we had to overcome early on was with having our renders not look like a level out of a videogame. We managed to fix that by making the rocks less shiny, as well as adding atmosphere, birds and other elements to give the viewer a hint of scale. I am unsure who worked on the birds, but it wasn't until the LUMA werewolves and birds were in place that we could finally get an idea of scale of the fortress compared to its citizens below.
Is there anything you did for Underworld that you'd really like to call attention to?
Actually the main thing that I would like to call attention to is that for the far shots we had matte painting extensions that were made by Jordan Nieuwland, so for the far shots I can't take as much credit. It had nothing to do with ZBrush, except that the matte paintings were somewhat blended between what I provided for the rocks and some areas that needed major reconstruction. There are also a few other closer up shots that just pan in one direction slightly that have some heavy matte painting because the models were not detailed around for whatever area that was needed.
How long have you been using ZBrush now? How were you first introduced to it?
Oh, man. This alone is a long story, but I will shorten it down a tad. I remember playing with ZBrush back around 2001 and reading up about it in magazines. It wasn't until us moderators at CGtalk/CGSociety were offered a complimentary license for being on the mod team that I asked for it. ZBrush was at version 1.23b I think. It had the base tools there for sculpting but it was all very primitive, with huge limitations on poly counts. I did really like what was there because as with drawing which I fell in love with in my early childhood, it was a very immediate tool it allowed me to be heavily experimental. I was also constantly on the Spiraloid boards and having shown interest in ZBrush I was asked by Pixolator to be on the beta for the version that would later come to be ZBrush 2. This was back when the big guy behind the tools would constantly post pictures using the tools he was creating. I miss those days.
It was super exciting because around that time there was still a really small testing team: a few guys at Weta Digital, and myself. It was really interesting to see ZBrush develop, seeing how the Smooth brush came to be integrated, the constant speed increases, etc. I remember making some mockups for the way the drop-down menus would work, where you could work within the menus themselves and not have merely single-function tools within the drop down menus like all other applications have. I made pages and pages of suggestions. A lot of stuff made it into 2.0, or later into 3.0. I am glad that I have been allowed to have been so involved in the initial sculpting tool development process, because it is a tool that has gotten me several jobs and is still providing me with work today. And since I use it for work frequently, I can always make suggestions on where the toolset could be improved to make it easier to do my job.
What does ZBrush do for you that other programs can't?
The list of actual tasks has shrunk ever since other tools like Mudbox, Modo, and 3d Coat have come on board to provide a sculpting tool set, but what they all lack is the versatility that ZBrush provides. ZBrush can be a one stop shop if you want it to be. Starting a model from a primitive or two, or custom made Zsphere models, a combination of those which you can append to, retopologize and the like, or even create a volumetric model from what you painted onto the Canvas. Being able to pose within the application really saves on time from having to rig a model if I want to repurpose a model as well, so that really helps a ton!. There's a ton of stuff that ZBrush can be useful for, like modifying displacement maps or textures on the canvas, without needing to go out to Photoshop. If anyone wants to see how versatile ZBrush is, I suggest they check out the work by Sebastien Legrain. The use of ZBrush by that artist is nothing short of brilliant. Or how Ryan Kingslein uses ZBrush for his anatomical studies, and how he fleshes out his models. While the result can be achieved elsewhere, it will usually either require several packages or the process just won't be as simple.
What is your favorite feature in ZBrush 3?
I am unsure if I can decide on any one tool, because it truly is the combination of things that really make the working process enjoyable. One of the things I personally like is the fact that the interface is very flexible. This allows me to construct a way of organizing the brushes and their immediate properties on the left side of the interface, the settings for brush mod, intensity, etc. on the bottom, and having the object/tool properties on the right. it makes my workflow very circular, and the whole application no longer feels like a piece of software but a collection of tools on my palette that I can grab and manipulate at any time. One thing I dislike about programs like Mudbox for instance is that I am forced to keep the tools on the bottom of the screen. On laptops (and even more so on Powerbooks) vertical space is very limited, so it can be a pain in the back side.
Can you tell us anything about your current project? Where we'll see it and when?
Currently I am working on a personal project which I plan to release as a set of images. I tried working up a "short film" a while ago but that went nowhere fast as I had huge expectations. I just wouldn't be capable of finishing it within a reasonable timeframe so I dropped the idea of completion. With a set of images however, I don't have to worry about rigging as much, or handing off the animation, or even working within a package for the sole reason that an animator or two would work in it. The idea this time around is that I have divided the project into many smaller elements for which each one could be handled as its own project. I then work down a list of objects that I will need and which tasks still need to be done for any particular object (like UV mapping). So far I have focused my efforts on the smaller assets and the things that will add some chaos/life to the images. The larger set pieces will come later once I finalize the previs. The idea is to use previously made models (like the monkey), create reusable tools (like the wrenches, bolts, nuts, etc.) and then build the larger set pieces. Once that is done and assembled in a scene, I will then go about texturing. I might utilize the Projection tools in Cinema4d/Bodypaint which allows me to sort of work on the scene as if it was a matte painting.
I haven't decided for when I would like to release it yet, but it would be nice to have something for the next time the next Exposé book comes around.
Perhaps I might even write up a book on the making-of, with a set of tutorials, a ton of images and breakdowns. I guess we will just have to wait and see.
At the same time, I am helping the guys at Rune entertainment with a few projects, and one larger project coming up in the next week or so. That should last a few months.
During the time of the next project I will also be presenting a master class at CG Overdrive. Should be fun, but I am a bit nervous about it because it is a longer format presentation and this will be at least double the size (in terms of people attending) of the largest presentation I've done in the past.
What do you like to do in your free time? Do you have free time?
When I can, photography. I love to travel and just do general landscape photography. It's just nice to have something more immediate than 3D, and going out to hike and explore dark alleyways, get beaten up by hobos or go into caves to get chased by bears -- its just a ton of fun. I love it!
Any other things you'd like to mention while you have our attention?
Thank you for the opportunity. And I would like to finish off with saying that I write way too much! I should stop. Really.
We'd like to thank Martin for providing such informative answers to our questions. It's been fun! You can view more of his work at his personal website, www.martinkrol.com. We would also like to thank Intelligent Creatures for consenting to the sharing of the Underworld images and video in this interview!
Be sure to also check out our many past interviews, which can be found in the ZBrush Artist Interviews forum.