Architectural visualisation is a powerful tool that gives architects and developers the capacity to bring nearly any concept to life–from quaint countryside neighbourhoods to cities of the future. Yet, when asked, most of us probably only have a vague idea how these representations that sell millions in property and land are made.
To give you a glimpse of what happens behind the scenes of an architectural visualisation project, we’ve broken the process down into 6 stages.
Stage 1: Modeling
As history’s most iconic structures started as a single block of stone, so do today’s most impressive CGI images begin as simple shapes. Each imagined building, neighbourhood, or city starts with basic, flat geometric shapes like squares and triangles.
Image from Blender.org
These are the building blocks of what then become polygons. Polygons are the complex shapes that–when connected together–form the wireframe that gives structures 3D depth. Or furnishings, if you’re creating an interior CGI. The more numerous and smaller your polygons are, the smoother the texture of your model.
Stage 2: Lighting
Lighting is an element that can make or break an image. Unnatural lighting, at best, can make it hard for clients to appreciate details and depth. At worst, it can lead to disastrous design flaws that can render a space dark and dingy, or even unusable. Properly rendered lighting also allows artists to control ambience and mood, further enhancing the impact of a representation.
Image from Redway3D.com
Light does not reflect onto surfaces in a vacuum. In real life, it takes on the characteristics of the objects it bounces against, changing the way light reflects around neighbouring surfaces. Designers mimic this effect using an algorithm called global illumination (GI). GI looks at the way light bounces off one surface onto another. The process is integral to ensure shadows and colour are represented as the eye sees them. You can see the difference the process makes in the image above. The picture on the left is before GI and the one on the left, after.
Stage 3: Materials
Materials are the assets that wrap around a 3D model and give surfaces their properties. Think of it like a 2D skin or map that designate the texture of an object. For instance, during this stage of architectural visualisation bare panels can be transformed into rough brick or glossy, smooth tile.
There are many ways to texture a 3D model. Architects can rely on an algorithm to procedurally create the textures, or use image maps of real photos of the materials to enhance photorealism. Some artists create materials from scratch, yet nowadays you can save considerable time with pre-existing asset libraries like texture.com or SWTEXTURE.
Stage 4: Camera Motion
A majority of CGI representations are static images. However, the beauty of architectural visualisation is in its flexibility and near limitless creative applications. The fifth stage is animating a representation, a process made possible by cutting-edge software like Maya or programs like Unreal Engine.
Screencap from Ocean CGI’s Church Farm Somerset Flythrough video
There are multiple ways you can inject movie magic into your representations. Property developers can give clients a 20,000 foot view of a neighbourhood or commercial space with fly throughs, or an architect can walk a family through their new home with a 360 panoramic video.
3D artists create animations by first setting a path for the camera. Computers then render every single scene as the camera moves. These images are called “frames”. The animation is created by sewing the frames together to create the illusion of moving through an imagined space.
Stage 5: Rendering
Rendering is the stage where all configurations and values are pulled together to create the final representation. The bulk of the job is handled by powerful computers or several computers networked together for increased processing power (known as a render farm). Depending on the level of detail needed and the cumulative processing and graphics power, it can take anything from a few minutes or hours to a day or more.
Rendering can be very time consuming and how long an image takes to render will depend on two things – the processing power of the render farms (ie how many threads it can handle) and how complex the image is in terms of realistic bounced lighting, reflections, textures and geometry (what we call ‘heavy scenes’).
To put things into perspective, to render a 4K highly detailed image on a standard home dual core intel processor would take between 15 to 30 hours. On a render farm like ours, it would take around 20 minutes.
Stage 6: Post-production
Post-production is the stage where elements such as dramatic lighting and colour editing take place to really bring the image to life. Foliage and natural landscapes, crowds and cars can be added at this stage.
One or two groups of people strolling down the street or a pair of shoes by the door in an interior CGI may seem incidental. Yet these elements can significantly increase the visual and emotional impact of a project. These objects help the client imagine themselves in these spaces, instead of simply being an outsider looking in at an impressive yet impersonal building. The post-production stage is also typically where artists and designers get to exercise a bit of creative flair.