Polantis presents the Case Study of the Wienerberger BIM approach: go behind the scenes for the creation of CAO & BIM shaders of the leader in terracotta.
The objective of the BIM approach
In October 2012, Polantis put online 29 brick textures designed for Wienerberger.
This incomparable specialist in terracotta began a BIM approach for a large panel of products: from traditional colored brick to more elaborate effects, and naturally-colored materials.
The goal for Wienerberger, a leader in terracotta, was to confirm its leadership position by putting itself at the cutting edge of innovation.
The issue for the team of architects in charge of the project at Polantis was as follows: with the wall covering being the first view of a project, it was imperative to reproduce with complete accuracy the aesthetic properties of the Wienerberger products.
The documentation provided by Wienerberger
Wienerberger provided Polantis with several sources with which to work: sometimes the photograph of a part of a wall, sometimes the photograph of an area of bricks superimposed but without joints, and other times views of the building in perspective.
The first action taken by the team of architects in charge of the project was to cut out and isolate each brick present in the photograph in order to keep its specific qualities in order to continue to showcase the richness of the material.
It was also necessary to “flatten” the views in perspective so that the user could perceive in total specificity the sizes and formats of the bricks modeled.
The 3D representation
There are four types of BIM objects: the simple object (for furnishings for example), the parametric object (for a product with variable dimensions), the system (for a product composed of several elements and variable dimensions) and the texture (for wall or floor covering, for example).
Wienerberger products are textures: what was needed was to represent a wallpaper that would be applied to a given geometry.
Because the bricks could not be modeled and assembled one by one, since this would be too fastidious, the architectural team designed an infinite texture that could be applied with a click on any wall whatsoever.
An infinite texture
An architect who wishes to apply a given texture could be satisfied with cutting and pasting an image of a “brick” taken randomly from an online catalog: the repetition would be noticeable and the resulting effect would not be natural.
The Polantis teams worked in Photoshop in order to adapt the texture in such a way that it would react like a real assembly of bricks.
The shader, a combination of layers
The term “shader” is used when there is a combination of several textures.
A well-made shader always combines 5 elements:
- “Diffuse”: this is a single layer which indicates to the software which color is to be applied to the object
- “Bump”: is the shader relief. Thanks to the Bump layer, the texture is realistic. This layer is composed of dark areas that represent hollows and clear areas that represent the surface.
- “Normal”: this is a special layer that only the software (Sketchup, 3DS Max, Revit, etc.) can interpret. It also contributes to the realistic effect. And it allows the user to simulate details and recreate irregularities in the material. This is a special filter that comes software specialized to achieve special effects: the effect is called “normal mapping”.
- “Reflection”: the material reflection, meaning its “smooth” effect, is simulated using a filter that is complementary to the “normal” layer: the more white there is, the lighter is sent back to the eye. This effect is most important to achieve a smooth and contoured appearance.
- “Specular”: specularity determines the clarity of the reflection according to Newton’s theory. It also contributes to making the texture more or less smooth and modulates the level of brilliance of the material.
On the Wienerberger page presented on the Polantis platform, all of these elements are presented next to the shader so that the experienced user can have a glimpse of what is found in the .zip he or she downloads.
This information allows prescribers to obtain in detail how the shader to be applied to projects is composed.
The final informational element accompanying the shader is a view from the Wienerberger catalogue: this will allow the user to note the absoluteness of the resemblance between the given file and the real object.
Exchanges with Wienerberger
The work of the Polantis architects was validated after a meticulous study by teams working with this specialist in terracotta. The attention on the part of the manufacturer was above all devoted to the realistic effect of the shaders. Certain elements had to be modified:
- Some colors were not faithful enough to reality: particularly the pigmentation of ocher-colored bricks which needed to be more irregular
- the junction between the bricks of certain shaders was overworked: this did not showcase sufficiently well the rustic quality of the product
The architect and the client
These points merited a high level of interest because the architect needed the project presented to his client using his software to be highly faithful to reality, so the image and the rendering were prioritized.
This fidelity allowed the client to identify with the result and validate the project more easily.
In the case of BIM, it is commonly said that the digital model allows one to “build before building”, so to present an object with realistic aesthetic qualities helps the architect and his client engage in more constructive exchanges.