[Genma Saotome]

In the late 20's Chicago built a new Civic Opera House and to ensure it had a steady source of income to support it's artistic efforts a rather tall (555 feet / 169m) and wide ( 385 feet / 117m) office building was built around 3 sides of the theater, giving a general impression of a big comfy chair. It's on the south branch of the Chicago river, directly across from both Union Station and the C&NW Downtown terminal. Given it's height and location it's a building that had to be included in the route.

I found this early photo somewhere on the web:


Building such a structure as a single flat surface per side would be the practical solution, but it would require painting from scratch a number of tiling textures to represent the different patterns of windows and walls that appear. I don't feel I'm particularly skilled in that regard and so I tend towards using generic photo based textures, of which I already have a large library (this model uses 6 fully tiling textures).

Add the fact that I don't always have a practical bent plus I wanted to experiment (again), this time exploring how one could make windows reflective -- windows being a significant visual feature of very tall buildings. So I decided to build the model with 3d features. I may subsequently create textures from this model and replace the original with a simple, flat surfaced equivalent, but this thread is about building Skyscrapers with 3d features.




The initial step of course is to build the flat walled building. I have the Sanborn map of this site and so the footprint was easy enough to measure. Getting the height was a bit problematic... sometimes it was hard to read, sometimes it wasn't shown in symmetrical fashion when I knew the building was, in places, symmetrical. Eventually I was able to figure out the various height and built a basic flat-faced structure. I then began to cut out and replace sections on one surface with repeating instances of floors and columns.

The first stage:


The basic structure is there and over on the north "arm" I've done an initial creation of floors and columns. The gaps between those are where the windows go and rather than create single quad polys for each window I created a large single quad that sits where the glass belongs and textured it as a dark, hishine surface. As you can see, that does accomplish the look of a large amount of glass reflecting the sky.



Being satisfied with the general look, everything that follows involves (2) extruding columns thru the center of the building so they poke out as 3d columns on the far side (the polys inside the building get shared on opposite exterior walls when they too poke out as 3d features) and (2) wrapping floors around he outline of the footprint and extruding them outside as 3d features (once again, all interior polys are shared wherever they have been extruded out). Doing one floor shape allows a copy/paste... up or down 15 feet to be the next floor, repeated as needed until all floors are present. Ditto for most columns except that the east:west run of the arms isn't identical so there are many sets needed to run thru the building.

These should help make clear what's going on:

A view from the northwest, looking southeast:

Showing most of the columns that run east:west:


Most of the columns that run north:south


And most of the floors:


The glass is done with large quads -- very low poly:


With the glass quads positioned inside of the floors and columns only that part that falls where windows are to be can be seen. The rest, as pixels in the screen, are simply culled away by the GPU, s task at which it excels. Essentially, all of the interior pixels are culled away by the GPU, the same as the far exterior sides are culled... out of sight, out of mind so to speak.


Putting what's completed so far all together, showing faces:


and just textures:


I'm using LOD's to suppress as many polys as possible:

From Zero to 250m distance: 2800 polys
From 250m to 500m: 1600 polys
Beyond 500m 1500 polys

I think I have about 200 polys to add in order to complete the building, a third of which be limited to 250m view ranges.



Viewing the building in-route, from the point of view of a pedestrian:


Looking upriver towards the Merchandise Mart:


Looking up from street level on Wacker Drive.


A closeup of the extruded polys giving the 3d feature effect.. each "step" away from the glass is 4 inches:


All quads that come thru the vertical plane of the wall run thru the center of the building and pop out on the far side, which effective makes any such face a cost of 1 poly, not 2, per exterior wall. Culling all of them with a 250m LOD helps reduce the workload when the camera is not adjacent to the structure.



Next steps:

I need to complete the model... a few more columns and then decide what to do about the street level details (many doors that fit into 30 foot high doorways). When done I have to address the question of whether I want to shoot screenshots of the faces to make textures for a flat faced model. As the building is not immediately adjacent to route-used tracks the normal view distance at 1920x1200 pixel screen resolution doesn't show off enough of the 3d detail to warrant the original poly cost. What I don't yet know is if I can somehow save the reflective quality of the glass polys. More experimentation with alphas I suppose.

That said, IMO the important lesson learned is the technique for making that glass look right does work. One just needs a busy trackside location to apply the full 3d effect, something this site doesn't have.

[Bernie]

Wow, that's stunning! :oldstry: Those windows are neat, how reflective are they? I mean, does the sun tracking across the sky change the reflective effect as the day goes by? After all, you essentially have four different faces to the building that the glass shows on, does the reflection properly display so one side is brightly reflective while its opposite side is dark and the sides show only moderate glint?

Sorry if I came out all garbled, but I'm guessing you will know what I mean... :sign_thanks:

[Genma Saotome]

Bernie, on 23 January 2013 - 11:59 AM, said:

Wow, that's stunning! :sign_thanks: Those windows are neat, how reflective are they? I mean, does the sun tracking across the sky change the reflective effect as the day goes by? After all, you essentially have four different faces to the building that the glass shows on, does the reflection properly display so one side is brightly reflective while its opposite side is dark and the sides show only moderate glint?

Yes for Open Rails the shine rolls across the glass as the sun and/or camera moves... I dunno for MSTS (other than route and activity editing, I don't use MSTS anymore).

[eric from trainsim]

Spectacular job. I have a low poly (90) version of the opera house in the Harvard, but that just looks incredible in comparison.

If you're looking for placeholders for other buildings near Wolf Point, I have the CNW HDQ twins, LaSalle Wacker, and North American Cold Storage. Can't think of anything else that is pre-war -- I'm set in the 70's, which means Morton Salt (now Boeing), the Sun Times and a bunch of other ugly glass blocks are also available if you're dating later than the 60's and need some filler.

[Gman347]

As Harry Caray would say "HOLY COW"! You have done a really fantastic job of capturing this building. As one who walks by it every day I can tell you really nailed it. And the reflective windows,,, Beautiful.

Bravo to you Sir! :sign_thanks: :oldstry: :good:

[Bernie]

The more I see of your work on this route, the more impressed I am. Not only are you putting in an incredible amount of work on unique structures, you seem to really dive into the research. Best of all, you have achieved a true regional feel with these structures (when folks see buildings like this, they know exactly what city they are in!), and you probably have the most dense industrial canyons I've ever seen in any sim! :thumbup3: I cannot wait to see this building when it is finished, with the big windows and arched detailing that faces the water!

[Noisemaker]

Holy cow indeed! :thumbup3: Looks like the Royal York hotel here on some serious steroids! Are the extruded facades on all sides? The view from Wacker St. looks like the opposite wall is merely 'flat' and could be textured with a 4 or so windowed tile carefully fashioned to fill the whole wall in one swoop. Or is that in fact what you did? For all the intricacies of it, 2800 polys isn't that bad really. I've dealt with 3D Models that were a third of your detail, and at 5000 to 9000 poly's.

[Genma Saotome]

Noisemaker, on 24 January 2013 - 09:49 AM, said:

Are the extruded facades on all sides? The view from Wacker St. looks like the opposite wall is merely 'flat' and could be textured with a 4 or so windowed tile carefully fashioned to fill the whole wall in one swoop. Or is that in fact what you did?

All sides of the building have 3d detail, just as you see in the view looking up from Wacker Drive.

Obviously if the light isn't right you don't see the extruded polys... which begs the question of why bother? I think the answer to that is circumstantial... how close is the detail to where the camera will normally be? Will the camera be most often looking at the south side of the building (where the sun will always shine) or the north side (which is usually in a shadow)? This particular building doesn't sit adjacent to route-used tracks and the view will most often be from the northwest (and now I know I probably should have done my glass experiment elsewhere; live and learn). OTOH, the Chicago Elevated CTA ran on Wacker Drive, right at the foot of this building... so if at some future date the El was added to the route, well, then the circumstances would be quite different. I do have to put a bit of the El into the route as it crosses above the route's MILW tracks (just a few blocks north and west of the Opera House) and so the idea isn't completely far fetched (just mostly so).

[Genma Saotome]

eolesen, on 23 January 2013 - 01:00 PM, said:

Spectacular job. I have a low poly (90) version of the opera house in the Harvard, but that just looks incredible in comparison.

If you're looking for placeholders for other buildings near Wolf Point, I have the CNW HDQ twins, LaSalle Wacker, and North American Cold Storage. Can't think of anything else that is pre-war -- I'm set in the 70's, which means Morton Salt (now Boeing), the Sun Times and a bunch of other ugly glass blocks are also available if you're dating later than the 60's and need some filler.

Thanks, but I think I've got things covered... already have something in hand for NA Cold Storage, both of the Butler Bro's buildings, the Merchandise Mart, and so on... settling into a 1945-50 time period keeps out modern glass cubes (even tho I think there are some GREAT examples of modern Architecture in Chicago).

I do have a question for you tho: I can't quite figure out if the North American Cold Storage building always had windows. Necessary for conversion to condo's but were they there before that? Do you know?

[Tony]

Hello Dave
That is quite the interesting building. I like art deco buildings. It's still in existence too and being used for it's intended purpose.

Cheers Tony B)