Realism and depth without a rendering engine: explore the possibilities offered by the diffuse texture map with shadows

The importance of shadows in 3D rendering

Shadows are essential for adding depth and realism to 3D renderings. They add relief and facilitate the perception of object textures and dimensions. Nevertheless, for reasons of efficiency, pre-renders in modeling software allow you to experiment quickly with different materials without having to generate a realistic image using a rendering engine.

However, generating realistic shadows can be a major challenge in modeling software such as Sketchup, known for its limitations in advanced light management, notably the lack of support for complex depth maps that facilitate more sophisticated shadow rendering.

Here's an example of a depth map (or displacement map):

Diffuse map with shadows

To overcome these limitations, the diffuse map with shadows represents an interesting solution. This technique involves integrating shadows directly into the diffuse texture of a material. In other words, shadows are "painted" onto the texture itself, enabling them to be presented consistently, regardless of lighting variations in the 3D scene.

Advantages

The main advantage of this method is that it avoids the dynamic calculation of shadows at render time, which can be very resource-hungry for the computer. Pre-integrated shadows ensure uniformity and consistency that are unaffected by changes in lighting, making the rendering process faster and less susceptible to common errors associated with light calculations.

Application example

A concrete example of the use of diffuse map with shadows can be seen in the profile of an exterior cladding. In the case below, details and shadows are much more apparent in the second image. This visually enriches the final rendering, offering a more detailed and realistic image even without complex real-time shadow calculations.

Product used: MAIBEC - MAIBEC CANEXEL - CED'R-VUE 9 - SIERRA

Diffuse without shadows

Diffuse with shadows

In summary

The use of a diffuse map with shadows provides a better solution to overcome the limitations of software such as Sketchup, Chief Architect, and Softplan, enabling easier creation of realistic renderings with fewer technical constraints. By integrating shadows directly into textures, designers can not only improve the visual quality of their projects, but also optimize the 3D modeling process. The simplicity and effectiveness of this technique make it well worth exploring for anyone looking to push the boundaries of 3D visualization.