9. ArchViz Theory – Representing Concreteness


In the previous article we discussed the role played by our senses while exploring a particular landscape. Now we will turn our attention to the process of representation and find concrete ways in which a visualiser can evoke tactile cues through 3D renderings or other types of computer generated imagery.

As Pallasmaa argues in his book, the current overemphasis on the visual realm while ignoring the rest of the senses has led to an architecture bereft of plasticity, warmth and human scale. In ArchVis, a perspectival representation reduces buildings to geometrical shapes. Whether it emphasises their graphic character (strong edges and articulations) or their surfaces, it still deals with mental abstractions. In many cases, adding colours to the 3D objects only accentuates the sense of a flat, immaterial and ultimately unreal representation.  In Pallasmaa’s words:

The detachment of construction from the realities of matter and craft further turns architecture into stage sets for the eye, into a scenography devoid of the authenticity of matter and construction. The sense of ‘aura’, the authority of presence, that Walter Benjamin regards as a necessary quality for an authentic piece of art, has been lost – Juhani Pallasmaa, ‘The Eyes of the Skin’.

In the previous article we concluded that the sense of touch is the parent of all senses, including sight, integrating every stimulus in a unified embodied experience. It follows from this conclusion that certain visual representations may evoke aspects of the haptic realm, triggering sensations of materiality such as solidity, spatial depth, texture, tension and gravity, temperature or scale. We’re going to discuss these triggers while offering some of our images as concrete examples.


Sarnath. Illustration based on a short story by H. P. Lovecraft



The classic method through which a visualiser represents the texture of a particular material is through the diffuse map combined with the bump and normal maps. These can reliably convey visual information about the smoothness, roughness and protrusions of a certain object.

In addition to these universal methods we aim to use more subtle cues that trigger strong tactile sensations. By opting for frontal views which frame a particular segment of repetitive or monolithic facades, we can bring forth concreteness. The repetitive texture of the facade captures the viewer’s full attention. The complexity and the self similarity of the material is pleasurable to behold because of its subtle variation, which is achieved not only through carefully avoiding the ’tiling’ effect, but also through the soft reflection of the textures in conjunction with a subtle sunlight.

Common sense tells us that only highly smooth and polished surfaces reflect light. The diligent observer, however, might notice that all materials, even the roughest or light absorbing ones, reflect a certain amount of light in a diffuse manner. This can be simulated in a 3D render by adding reflection and refl. glossiness maps (in VRay), resulting in an increase of the realism and concreteness of objects. The second aspect contributing to this effect is the character of natural light. Instead of having strong, crisp shadows that would accentuate the graphic, perspectival character of the composition, we sometimes opt for subtle transitions from areas in direct sunlight to soft shaded areas. A good way to achieve that is through replacing the classic Sun-type light with an HDRI system. This not only leads to softer shadows, but also reflects some of the colours of the sky dome on materials, increasing their realism and integrating them in the atmosphere of the landscape.


Foxfield – illustration for Stygian Fox’s ‘New Tales of the Miskatonic Valley‘, Call of Cthulhu RPG


Although the materials of the houses in the image above are repetitive, the viewer is enticed by the subtle variations achieved through the reflection of diffuse light, the gentle transitions from shadow to sunlight, the small imperfections of the textures that make them seem real.



The feeling of depth also relies on the sense of touch; haptic memory enables us to understand the three-dimensional nature of landscape, making us aware that things extend away from us in all directions (Pallasmaa, Idem).

The Outsider. Illustration based on a short story by H. P. Lovecraft

We’re always interested in conveying a strong sense of depth. This is partly achieved through atmospheric effects – a discrete distance haze (which may be realised through the use of the ZDepth render element in VRay), a gentle mist over the flowers in a garden, a torrential rain, the smoke coming from chimneys or the glow of surfaces in direct sunlight.

Composition is also crucial in conveying a sense of depth and atmosphere. By extending the horizontal edges of the image until it reaches a square format, the composition gains more sky as well as foreground, almost inviting the viewer to step into the scene and become immersed in its atmosphere.

Mist and twilight awaken the imagination by making visual images unclear and ambiguous; a Chinese painting of a foggy mountain landscape, or the raked sand garden of Ryoan-ji-Zen Garden, give rise to an unfocused way of looking, evoking a trance-like, meditative state. The absent-minded gaze penetrates the surface of the physical image and focuses in infinity – Idem.

When shown the image above, the viewer will immediately focus on the centre of interest: the castle in mid distance.  The eye perceives things in such a way that the central line of sight gives the best focused perception of colours and shapes in daylight. The peripheral areas (left, right, up and down) have an unfocused gaze and support the vision of the eye under low light conditions (scotopic vision), aiding perception in general, enfolding the viewer in environment they find themselves in. By extending the upper and lower edges of the image above, we are aiming to integrate the unfocused peripheral vision in the process of perception. Quite often this is doubled by a subtle vignette towards the upper and lower edges, further helping scotopic vision.


The Town Manager. Illustration based on a short story by Thomas Ligotti


The value range of colours and the balance between lights and shadows is also carefully addressed so that it contributes to the atmosphere of the image. Sometimes opting for low- key, other times for high-key values or something in between, lights are never dull and repetitive. With subtle illumination in darkness, one begins to understand form to establish connection and feeling, creating a relationship between the building and the viewer. Pallasmaa makes a similar point when writing about the importance of shadow and peripheral vision in conveying a sense of atmosphere and bodily presence:

Deep shadow and darkness are essential, because they dim the sharpness of vision, make depth and distance ambiguous, and invite unconscious peripheral vision and tactile fantasy. How much more mysterious and inviting is the street of an old town with its alternating realms of darkness and light than are the brightly and evenly lit streets of today! The imagination and daydreaming are stimulated by dim light and shadow. In order to think clearly, the sharpness of vision has to be suppressed, for thoughts travel with an absent-minded and unfocused gaze. Homogenous bright light paralyses the imagination in the same way that homogenisation of space weakens the experience of being, and wipes away the sense of place. The human eye is most perfectly tuned for twilight rather than bright daylight – Pallasmaa, Idem.

Last but no least, the sense of depth and atmosphere is conveyed through the careful and restricted use of colour. In real life, especially during cloudy days, the variety of colours we encounter around us is somewhat limited; there’s a general hue given by the sky which is reflected in all the materials in the scene. This is why using too many colours in a single image can easily destroy the sense of concreteness and atmosphere. Refraining from doing so is also our approach; we tend to prefer moody atmospheres expressed through a dominant colour, rather desaturated and cold.


In a Foreign Town. Illustration based on a short story by Thomas Ligotti



The use of artificial building materials contributes to the loss of concreteness. On the other hand, natural materials instantly evoke strong haptic sensations.

Stone, brick and wood – allow our vision to penetrate their surfaces and enable us to become convinced of the veracity of matter. Natural materials express their age, as well as the story of  their origins and their history of human use. All matter exists in the continuum of time; the patina of wear adds the enriching experience of time to the materials of construction – Idem.

Instead of opting for glossy artificial textures, we prefer natural materials whose imperfections and variation is fully present in their images. Incorporating a photo of a natural material as a texture in your render will always surpass the use of generative algorithms in terms of realism. Aged bricks, aged metal, dirt, patina, fallen leaves, ivy climbing on walls – they all confer a sense of age to the represented landscape. The viewer is no longer in front of an ageless abstract representation that could be located everywhere, but in a particular place with a specific ‘genius loci’ and an accumulated history.

In the words of the American therapist Gotthard Booth, ‘nothing gives man fuller satisfaction than participation in processes that supersede the span of individual life’. We have a mental need to grasp that we are rooted in the continuity of time, and in the man-made world it is the task of architecture to facilitate this experience. – Idem.



The temperature of materials is another tactile cue that can be evoked through visual means. Notice the colours in the image above. When a surface is hit by direct sunlight its texture inherits a warm bright orange-yellow hue and its saturation decreases. When it is in shade it shifts towards a cold dark blue mixed with purple or cyan and its saturation increases.



The last element which confers an ‘aura’ of presence and authenticity is scale, an indispensable element of visual perception that’s also reliant on haptic memory, as Pallasmaa argues in one of the most poetic paragraphs of his book:

I confront the city with my body; my legs measure the length of the arcade and the width of the square; my gaze unconsciously projects my body onto the facade of the cathedral, where it roams over the mouldings and contours, sensing the size of recesses and projections; my body weight meets the mass of the cathedral door, and my hand grasps the door pull as I enter the dark void behind. I experience myself in the city, and the city exists through my embodied experience. The city and my body supplement and define each other – Idem.

The Strange High House in the Mist. Illustration based on a short story by H. P. Lovecraft


Although the texture, solidity, and age of materials can create a sense of human scale in a 3D render, the most effective means of doing it is by placing human figures in the scene.
Instead of using 3D models, we prefer using photos of people. Their scale, colours, lights, contrast and saturation carefully match those of the 3D render. The most interesting aspect, however, is their positioning within the compositions. Never too close to the foreground or in unnecessary locations, the people contribute to the framing of architecture, improve the composition of the image and guide the viewer towards the point of interest.

All the effects mentioned above combine to create a strong sense of concreteness and bodily presence. They are excellent ways to incorporate and reinforce the unconscious tactile ingredient in vision. By using them in your creation of visuals you might replace the all too common sensation of flattened pictures projected on the surface of the retina with the strong sensation of a bodily encounter.