Design and Technology – Communication | e-Consult

Within CAD software, material representation and shadows are vital for conveying the form and texture of a furniture prototype. Material representation involves assigning realistic material properties to the different components of the furniture. This goes beyond just colour; it includes parameters like:

• Colour & Reflectivity: Assigning appropriate colours and reflectivity values (specular highlights) to simulate different materials like wood, metal, or fabric.
• Texture Mapping: Applying texture maps to surfaces to replicate surface details such as wood grain, fabric weave, or metal brushing. This can be achieved using photographic textures or procedural textures generated within the software.
• Bump Mapping/Displacement Mapping: Using bump or displacement maps to create the illusion of surface detail without significantly increasing the polygon count. This is useful for subtle textures like wood grain.

Shadows are generated by the CAD software's rendering engine and are crucial for defining the form and volume of the furniture. The student can control shadow properties such as:

• Light Source: Positioning virtual light sources to create realistic shadows. Multiple light sources can be used to illuminate the furniture from different angles.
• Shadow Intensity & Softness: Adjusting the intensity and softness of shadows to control the overall mood and realism of the image. Softer shadows can create a more diffused and gentle look.
• Shadow Direction & Falloff: Controlling the direction and falloff of shadows to enhance the sense of depth and realism.

By carefully combining these techniques, the student can create a photorealistic representation of the furniture prototype, allowing stakeholders to better understand its design and form. For example, a wooden table could have a wood grain texture map, specular highlights to simulate the sheen of varnish, and shadows cast by the legs to define its three-dimensional shape.