Before I hand it over to Alex, Let me just say that this might not be the typical making-of article you would expect, since it does not show actual settings accompanied by viewport screen-shots. The main focus of this article is the animation, with actual snapshots added to support the text which turned out to be long, but very informative. A second part might be published with more specific in depth material… but lets wait for your feedback first 😉

And now… to Alex,

THE HOUSE

Before we dive into the details of this project here is an overview of the house from outside at dusk and the video. You can find a full set of the images in the Inspiration section – ‘The House’ by Alex York.

BACKGROUND

“The House” is a project that started life for Atelier York back in 2008, with a commission from the architects to produce a few relatively simple exterior renders of a new project they were working on, to better help them visualize their design. We were then asked to produce planning stills showing the proposed building in situ and its (very modest) impact on the existing building and landscape. A fly around animation was also produced. The building was granted planning permission and this quickly evolved into commissions for detailed, full-scale visualization content, including high-res externals, detailed interiors, updated fly around animations and, finally, two 7 minute fly through animations. The first to show the primary spaces within the house and to convince the Client to green-light the project, plus a fly around of the exterior, the second to show the secondary spaces and to help the Client choose finishes and to tweak details.

After almost four years of hard work, we are thrilled to finally be in a position to present the studio’s “Highlights Reel” – a collection of our favorite shots from the full 15-minute animation, with accompanying stills. In total, over the last four years, the studio has produced over 15 minutes of animated footage for the client, and more than 40 still images.

We enlisted the help of several well-known industry professionals and services including London-based freelance artist David Connolly of Insightful Light, Workstation providers BlueGfx and RenderNation, the studio’s render farm of choice for demanding projects.

THE PROCESS

CAD

The fly through part of this project kicked off in early 2010. The architects supplied us with an enormous pile of DWG CAD drawings for the interiors and some mood boards, sketches and material, lighting and furniture specs. At this stage we already had the full exterior model including the landscaping completed, as we’d already produced a set of exterior stills for the Client’s approval.

CAD drawings were stripped of any blocks, hatches and text using the usual filter command. The plans that were supplied to us were construction drawings, so they contained a lot of unnecessary info that could be removed for modeling. All CAD drawings were moved to the original to remove any possibility of distortion when imported into MAX.

MODELING

The first step was to take our existing exterior model and model up the interior spaces.

The modeling process itself was relatively straightforward. There was an enormous amount to do but it was just a case of getting our heads down until the work was done. Approximately one month was spent producing the furniture and lighting models alone, with one further month working on the structural geometry and facade details. We used stock libraries for a few pieces but the majority of the furniture was either bespoke (designed by the architects) or antique and not available online. In total I think there are over 500 unique pieces of furniture, artwork, lighting fixtures and design objects in this house.

All of the modeling was done using poly modeling with frequent use of the Slice command (and quick slice) to cut holes in ceilings for the spotlights etc. Virtually every corner of every wall and shelf was chamfered to allow for extra detail. We used a fantastic script called Stone Placement Tools to create the stacked island stone wall shown in the pool gallery space.

Here is a video showcasing what this script can do.

We produced our own little script to automatically go through the thousands of unique stone objects and set each one’s Turbosmooth value to 2 or 3 depending on their scale in the view, to keep rendering fast. We also made great use of the wonderful Grass-O-Matic plugin to generate all the grass and bamboo objects. We used everyone’s favorite ivy plugin IvyGen to create the ivy for the entrance walls and the retaining existing walls surrounding the site.

Once completed to an initial level of detail, white renders were supplied to the architects for comments and refinements made as needed until they were able to sign the geometry off. We used approximated camera positions/views that we knew would roughly match the animatic cameras, to make sure that they weren’t commenting on items that would never be seen in the final piece.

ANIMATIC AND ANIMATION

With all the interior spaces’ geometry signed off, we pushed on with producing the first draft of the animatic.

They also supplied us with their own storyboard (a simple set of camera paths drawn in plan for each floor), which we used as a basis for our own animatic. Refinements were made to their paths based on discussions in various meetings. One of the main requirements of the architects was that we needed to show as much of each space as possible, so creative camera moves were limited somewhat. We kept the sequences as short as possible and tried to avoid the usual “walk-through” look present in a lot of architectural animations, opting more for a smooth-flowing path through from space to space.

We used ease-in and ease-out for the camera paths and used Bezier controllers on the Path Percentage element to control how fast each shot progresses.

Moving objects such as doors, mirrors and windows were animated simply using key frames. The architects (and we) were keen to keep animated objects to a minimum, as this was more about the spaces and not the items within them.

MATERIALS

We work solely with Arch&Design materials, to ensure maximum realism and photographic/physically based results in conjunction with the Daylight System and our Photometric lighting setup. We created a library of common “house materials” that were specified by the architects, from a simple white plaster and the wood floor to more complex materials such as the bumpy, dark bronze, the slatted stone and the island stone silver/brown walls on the lower ground floor.

Samples were provided to us for all the materials. Photos were taken at the architects’ offices and brought into Photoshop where any obvious unique “hotspots” were painted out and the maps made tileable (manually, using Offset). Any very strong colors were de-saturated, particularly from the main dark wood texture, to ensure that when warm sun hits those objects the wood doesn’t go green/yellow.

For the main dark wood material and floor wood material we used edited Arroway textures maps, including reflection maps. We did not use any Arroway bump maps on any materials, since the effect would not have been noticeable in the shots and would have increased render times enormously. Since most materials had some degree of reflectivity, there would be enough visual detail in them not to have to worry about this.

The main challenge with materials was the large expanses of the dark wood, particularly in the basement and ground floor. In order to keep render times as low as possible and to remove the possibility of speckles and fireflies, we used the Falloff to Color distance limitation in the A&D materials for any glossy reflective materials. This setting forces MR to stop reflecting the environment and objects beyond a certain distance, usually a few meters. Beyond that distance, you tell MR to reflect a solid color, such as a mid grey or light blue. To give one example, one of our shots was taking around 25 mins per frame to render with this disabled, and there were some speckles in the wood. With it enabled, just on the wood, it went down to 4 minutes per frame, and the speckles were gone.

Ambient occlusion was used on most of the materials throughout the house, particularly on the white and cream plaster (ceilings and walls), the floor and any large expanses of a particular material. Initially we used “real” occlusion that picks up the neighboring color of objects, for more realism, but this quickly killed our render times. Removing this and forcing the AO to be one solid color (usually a light grey for the plaster) brought render times right down and the results looked almost identical. We will talk about passes and why we didn’t render AO passes a little later.

One of the main challenges was handling the glossy reflections in the dark wood, particularly in the shots where it was most visible such as the basement shots. We initially tried using interpolated glossies but MR simply can’t handle this properly without some serious post-work being required to clean it up afterwards, negating the speed benefits somewhat. In the end we had to go for a brute-force approach and simply crank the glossy samples right up where needed, anywhere from 32 up to 64 in places. We had the render-farm standing by so this wasn’t such an issue.

The two most challenging materials to create were the floor of the pool areas and the books used throughout the scheme. Both were produced by using Multi-Sub Materials with many different variations on the base material (i.e. 12 different variations of the Vals Quartzite and 15 different book textures). We used the Material By Element to randomize the IDs and shifted the seed until a good, random generation was found.

The fireplaces were handled using bought footage of fire from a stock website. The footage was duplicated and mapped onto two rectangular planes, one behind the other to give depth. Subtle lights were placed just in front of each fireplace to throw some warm, flickering light onto the floor and objects nearby.

LIGHTING AND RENDERING

Lighting for this project was handled almost entirely photometrically. The architects had used a lighting designer to specify the exact lights and bulb types for all the fixed lighting in the house, such as spotlights and floor lights, even the garden lighting. We used the spec images and drawings from the lighting manufacturers’ websites to model each light source accurately (e.g. Rectangular, circular, long strip, tall strip, cylindrical cold cathode etc.) and, where possible, initially started by using the manufacturers’ supplied IES data. We knew that we didn’t want to be using real IES data for the lights in the final renders, since you don’t get much control over spread and the cone shape, but we used the IES as an indicator for how each light should roughly look and then replaced it with a normal photometric spot or spherical light, or in many cases a Line or Cylinder shaped Photometric light.

Almost every spotlight in the house has a real size and therefore real “area” shadows. In order to keep render times down, we started with only 8 shadow samples for each light and increased as necessary up to a maximum of 32 samples for very large lights and flood lights (coming down staircases for example). If we could get away with point lights/shadows we did. These were normally used where the light was so close to an object which blocked it that there would be no visible effect of using anything other than point, and kept render times manageable.

Every single light in each scene had attenuation enabled and set either just beyond the bounds of the scene (.e.g. 12m>15m) or smaller if used for creative purposes. Again, this helped keep render times down.

Specular was disabled for every single light. We wrote a little script to do this with one button push, which can be found at our site under Tools for Artists. Using specular on lights in Mental Ray (and other renders too) can often result in speckles and fireflies on your objects. Disabling this fixes it.

Occasionally, non physically based lights were used. The most obvious examples of this are the dusk shots, where a simple Skydome was used, with a solid color, and a Gradient background map. We simply needed to find a suitable light level for the main scene lights to compensate for the fact that this wasn’t physically based, but it worked very well indeed.

We avoided using Global Illumination where possible, to simplify our workflow. We also found that some scenes required such enormous numbers of photons to resolve blotchiness and color-bleeding that it negated the speed benefits of using GI in conjunction with FG. Some scenes rendered faster purely using FG, and were easier to control. We kept the number of FG bounces down as low as possible and used as much direct light as possible to keep things snappy.

Exposure was handled entirely using MR Photographic Exposure. We found that a white balance of 4500 was perfect for most of our scenes. All of the ceiling spotlights were set to a WB of 4500 to ensure pure white light hits pure white walls, for correct WB. Warmer lights tended to sit at around 3500>4000 and cooler, bluer lights up at 4600-5000.

The strip lights proved an interesting issue with this project. Mental Ray simply cannot handle Photometric Line/Rectangle/Cylinder lights using normal FG Interpolation. At the default interpolation of 50, these light types are almost guaranteed to “bleed” onto neighboring objects. E.g. A strip light bleeding through a ceiling cove.

In order to solve this you can reduce the Interpolation right down to something like 10>15 or so, but you will end up with blotchy FG, so you must compensate by using many more FG points and much denser settings. Inevitably, this slows renders down hugely. We did use this technique on some of the stills, but for the animated shots we chose to fake the effect of strip lights by using a very simple gradient on a rectangular plane, set to fade off using the same gradient in the Cutout slot. These objects gave a very good effect and rendered in no time at all, and didn’t flicker. The only limitation of this is that you cannot use AO on any materials/objects that are directly behind/underneath these faked lights, since they will render with artifacts. You simply disable AO for those objects. Another way of doing this is to use self-illumination on the material and actually light the scene using FG, but this requires enormous numbers of FG points and was not practical here.

Caustics were faked. We used the Caustics Generator (free online) to generate our repeating/looping map and simply projected it through a normal light. This effect can be seen in the pool shots and the snooker room shots.

As I mentioned earlier, we made the decision not to work in passes for this project at all. This was done for the reason that we knew that the architects would need to see many different versions of each shot in draft form, and there simply wouldn’t have been time to re-render many different passes for each shot. We had almost 40 shots to render just for the second part of this project and well over 80 in total including the first part, so we needed a workflow that allowed us to tweak based on their comments, render and simply send it off to them as-is for approval. It also meant that post-production was extremely straightforward. Naturally this approach relies on your ability to “nail” your shots out of the box, with only minor color corrections and effects work needed in post.

Anti-Aliasing is always our worst enemy. We kept the threshold quite high for these shots, at 0.06 but used 1-16 samples to ensure there was no noise visible. Lock Samples was disabled and everything was rendered using Box filtering, which was more than sharp enough considering these were mainly animated shots. The stills were rendered at anything up to 0.02 threshold and Mitchell filtering, since they took no more than one hour each. We kept the blur values for texture maps tightly controlled, so that textures that required fine detail (such as wood) had low blur values (0.05 or 0.07) and textures that didn’t need such fine detail (such as plaster and the armourcoat render) were at the default of 1.0 to keep things quick.

Every shot was rendered at 720p 32-bit to EXR. This gave us the maximum flexibility to re-expose as needed in post. In the end, there were only perhaps 2 or 3 shots that needed a little re-exposing, and only a few objects within those shots. One good example is the snooker room shot (02:35), where the sofa on the far right was completely over-exposed but the rest of the scene was perfectly exposed. It was not possible to fix this in the scene itself, so we simply rendered a channel for the sofa and decreased the exposure until it matched the rest of the shot, with no noise and no artifacts present.

Many of the still shots were mapped onto curved planes and re-rendered with a moving camera to give the impression of a true 3D pan. We also used subtle zooms and pans to help animate the spaces.

We created a very strict check-list which was broken down into sections – Modeling (deleting unnecessary CAD, frozen objects, collapsing as many objects as possible), Lighting (turning attenuation on all lights, turning off specular on all lights, shadow samples etc.), Materials (checking wood materials had enough samples, checking flipped normals, using faked AO, removing unnecessary bump maps) and the usual general scene checks such as file paths and making sure there are no missing maps or proxies.

In order to allow the architects to comment (and hopefully sign off!) the shots, we rendered several stills from each shot along the camera path. Once these were signed off, everything was checked, double-checked and triple-checked and the FG passes (and GI passes where used) were rendered in-house on our relatively small farm. Once complete, everything was packaged up and sent to Render Nation for testing. They supplied us with test frames so we could check that everything was spot-on and the final renders green-lit.

POST-PRODUCTION

As we mentioned earlier, our workflow for this project was very much to get everything working as well as possible out-of-the-box (i.e. Straight out of the render). However, there are always things that need tweaking in post. The most obvious of which is the tone and general warmth of the shots. The architects were keen to ensure that the family spaces were warm and welcoming to match their softer furnishings, while the more staff-based areas were kept cool. The other most common post technique was to add faked depth-of-field to the corners of the shots. This was done with a very simple painted mask and a little Gaussian Blur. Light vignetting was also used to draw the viewer’s eye to the focal point of each shot (usually the dead center). We also added subtle glows and glints to some of the shots, especially to the chandeliers and other exposed light-sources. This was done by rendering a simple black-and-white channel for the bulbs and using that as a mask to generate the glints/glows. Subtle glows were added to most of the lamps using this technique.

The only element of “compositing” as such was to add the background pass to each shot. This was done very simply by layering the beauty pass over the background pass and applying relevant color-corrections, blurs and glows to the background to comp it in convincingly. Glows were particularly useful in allowing some light from the BG to spill “inside” (i.e. On top of the beauty pass).

Inevitably, there are always a few artifacts and issues to fix in post due to certain materials not behaving as expected, unwanted noise etc. We made extensive use of Render Subset of Scene to re-render new/fixed objects over the original beauty pass to handle this process.

One of David’s more inspired moments was to go out and shoot video footage of some tree canopies outside our studio. We comped these over the final exterior night shot, added some depth-of-field and color-corrected to match the render and BG plate. It looked so successful that we used some of these tree footage files through windows in many of the still shots.

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