At first glance, this image might look like an ordinary scene: Just a minute ago, someone wrote a letter. Now the pen still lies openly on the desk and the person is lost in thought. A bird flies in through the open window. Suddenly, some strange things happen: The decorative wooden animals on the desk become alive. The elephant drinks some water out of a barrel, the giraffe feeds off a suddenly grown tree, the wooden bird starts singing a melody and the tiger roars at the bird, which just considers quietly the curious view. Does this really happen, or am I lost in reverie?
In the lecture I was fascinated by the different possibilities of generating textures. Therefore, I have chosen a scene that allowed me to experiment with them. I did not use an external program to model the scene, I added the assets directly to the ray tracer and scaled and positioned them by using instances (for the used assets see References). However, except for the real bird, the tree and the barrel I just used the shapes and created my own textures. This happened for various reasons, sometimes I just wanted to try something different, other times I did not like the provided texture or unfortunately it did not work or was not available. First, I experimented a lot with procedural textures to create marble and wood. However, the only procedural texture left in the final version is the marble texture of the fountain pen. It is really hard to create a procedural texture that actually looks like wood! You can see my trying in the right picture next to the marble texture. Thus, I switched to image textures to create the wooden materials (all used images can be found in References).
When I finished the ordinary desk scene, I was a little bit disappointed of the resulting image: It looked nice, however it also was extremely boring. That was when the idea of adding some surrealism was formed. And in my opinion, it serves its suppose to breathe new life in the scene.
I mostly used the already implemented features. For example, the depth of field camera emphasizes the disparate confrontation between the real bird and the wooden tiger. The lighting is modeled by two area lights, one left and one right above the camera to produce soft shadows, and a directional light to illuminate the scene. The direction of the light is from below nearly parallel to the surface of the desk, so I avoided a third shadow for each object on the desk and on the back wall arises an interesting silhouette of the scene.
The marble texture of the pen can be found in rt/textures/marble.h. It is a procedural texture using three different tones of blue color. All wooden textures are mapped to the primitives using a plane coordinate mapper. Especially for the wooden giraffe and the tiger, I tried to choose a kind of wood and a projection such that the wood looks similarly to their natural skin patterns. To keep a texture while scaling and translating an object I extended the coordinate mapper by a few additional arguments.
The ink bottle is modeled by three nested instances of a little pot: Two whole pots of glass, one minimal smaller than the other and with the reciprocal refraction index, the third one only half and with an ink like color.
One more detail you can find in the right back corner: A stone with an engraved heart. This object originated from my fascination for bump maps. The bump map of the heart is projected on the stone by a plane coordinate mapper. Therefore, I extended the solid class to accept an image texture as a bump map and a second coordinate mapper as the mapper for the bump map.
The surface of the desk is modeled by a combined material consisting predominantly of a Lambertian material with the wood texture as its diffuse material, a Phong material and a fuzzy mirror material. The mirror material is included in the left image and excluded in the right image. You can recognize the Phong material in the lower right corner of the image by the whitish edge of the desk. The effect of the mirror can hardly be seen, you can see it best at the reflection of the pen. If you compare both images, you will notice differences in the shades on the desk. In my opinion, the mirror material makes the desk look livelier.
Rieke de Maeyer
This image was produced for the Rendering Competition 2017/18 at Saarland University.