Artist: Juan Sequier
Posted in: Skymedias
In this tutorial I will go through my usual workflow with simple steps (trying to make it as simple as possible), to build a scene from preparation phase of the project (Pre-Pro) to the final render. As usual, I'm using 3D Studio Max for the modeling, mapping and lighting, and Photoshop/Bodypaint for texturing-based off the great 3D Total collection of textures.
A good habit from the start is to create a special folder for the project, another subfolder for the textures and another for the references. Another advice (I always do it) is to print one of the references so you can look at it, whenever you go to bed or a bathroom break - in this print I usually write some notes and ideas to help me reach the final image.
I start with the modeling by extruding the floor of the building, then I make cuts on the geometry with the "slice plane" tool or also the "cut" tool, and then I extrude in negative to make the windows. Each time I finish the modeling of one of the elements, I also finish the UV mapping. I don't like to accumulate the UV mapping for the end. A few paragraphs below, I will explain briefly my technique for mapping.
In this kind of symmetrical building, it's very useful to apply the "symmetry" modifier because this way, we can save a lot of time and work since this guarantees the perfect positioning of windows on both sides.
If the composition of the reference picture satisfies me, I usually lay the 3D model over the picture as perfectly as possible - this way I can fix proportion issues. Using the hotkey "Alt X", I can make the object transparent to make the overlaying process easier.
For the antennas and cables I usually model it with renderable splines, making sure that I've activated the automatic mapping. I also watch my poly count, as I know from experience that a cable of 4 spans is enough if it's going to be seen from a medium/far distance.
The trees at the bottom of the picture were made using Onyx Tree Pro. Only the visible parts were modeled... in other words, they are incomplete trees.
For some reason I found it more simple to deform the bird neck with some bones, and a skin modifier. With this approach, I could move the bones in an interactive way to decide the final pose of the animal (always use the rendering camera, so it has more strength in the composition).
The mapping is without a doubt the heaviest and most boring process when it comes to creating the scene. It is a necessary, but not too creative process. Also the UV maps are not something spectacular to show around saying "Hey check out my cool UV map". But in the long run, uvmapping is more like a puzzle game (it has its charm). To describe briefly my mapping process, you just have a few simple rules:
1 - You should not have overlapping UVs EVER.
2 - The checker map we put on the object has to represent perfect even squares.
3 - The objects in the UVeditor should have the same proportion as the ones in the scene.
4 - Make sure the orientation of the object is correct in the UVmap editor.
5 - It is convenient to optimize the space inside the map.
A good way to begin the mapping, is using planar maps to unfold the object and then stitch the individual pieces together, also you could equally stitch the pieces from automatic mapping. I've assigned the hotkey"S" for "stitch", where I can select an edge, and hit "S" and stitch pieces together really fast. Always remember that if you put a lot of effort into the UVmapping, it will be less likely to have problems ahead once we've painted the textures in Photoshop.
Once I have all geometry modeled and mapped, I bake the Mental Ray ambient oclussion map. Usually I end up using that map as a dirt map. This map is very very important because I use it as a base to fake the GI, reflection masks, specularity masks and transparencey masks, (when it comes to crystals and windows). The aforementioned "baking" can be done with the "render to texture" in Max7, which is finally compatible with Mental Ray
Ok! Let's think for a moment that we don't want or we don't know how to bake the ambient oclussion map (maybe you don't have Max7) what we can do is use it on the diffuse level slot of an ONB shader (making the roughness 0)
We can combine the layers in Photoshop - underneath color > then the baked AO > in "multiply" mode and in top > "screen" mode the capture of the UVmapping which we can obtain, thanks to the free plugin Texporter.
The next task is to include the textures that I have chosen from the 3DTotal collection, in the mentioned layer of color, make them overlay with UVmap captured from Texporter. Normally I also use photographic maps in grayscale which you can find in TotalTextures Volume 5. Include these layers on a top layer so you can multiply them. Naturally you have to make a lot of touch ups with the Photoshop brushes by hand, so you can paint non-mathematic dirt, cracks, and the like. I also highly recommend a graphic tablet - I use a Wacom Intuous 2 A5.
It is very tough to make the textures overlay perfectly with the model if you don't have good continuity on the UVs. What I mean by this is that if the UVs do not have seams, you could always use Bodypaint so you can paint directly into your model or use the clone stamp as well. I usually bring the model to Bodypaint to make the final touches adding dirt in those places where the math calculation of AO does not happen.. for example, the oxide rake that leaves the rain under iron elements.
To light the scene I decided to use a target spot light very far away from the models with area shadows, using a yellowish-orangish color. I activate the ambient lighting on Vray with a little bit of blue color, and as well, I activated the GI with some predefined values (I think "High" preset) on the irradiance map.
Usually, I model the shadow casters with the help of the "light" viewport (Shift+$) so the shadows are projected exactly in the desired place.
Finally I start the render at 3000 px resolution and adjust little details in Photoshop like levels, and a couple of brush strokes in the sky as a "final touch". Generally I condition all the work so as a result, it's closer to an illustration where the focus is the beauty of the form and color instead of an accurate representation of the building.
All the textures of this image were taken from the huge colection of total textures of 3D Total - the color maps, the bricks, wood and concrete as well as the dirt maps.
I hope that this has been useful in helping you to make old buildings. I find it really enjoyable so I hope that you've enjoyed it too.