Plain Dreaming
by Philip Hell and Matthias Frauer

This image was created for the Rendering Competition during the lecture Computer Graphics, held by Prof. Dr. Philipp Slusallek at the Saarland University in the Winter Term 2017/2018.

This composition exhibits an intimate living room scene. The projector shows a movie with planes, while a small toy plane rests on a kitchen countertop, in clear sight of the screen. Maybe it's dreaming about growing up and being a cool plane as well. We chose his setup to make our rendered image more intriguing, so that the viewer gets hooked by it and studies the created effects like lightning, reflections, shadows, textures and materials.

Renderer Features

Projective Light

We used a projective lightsource, that projects an image on the projector screen. Objects that lie between the source and the screen, are illuminated by the respective colors.

Also shadows are cast, where the object blocks the lightsource.

Implementation: rt/lights/projectorlight

Combine Material and Soft Shadows

A combination of different Material Properties (here Lambertian and Fuzzy Mirror) creates partially reflecting surfaces.

Area lights illuminate parts of the scene to create a natural looking soft lighting. Other lights would have casted too hard shadows.

Implementation: rt/materials/combine and rt/materials/lights/arealight


Our glossy Phong Reflection Model approximates local illumination in relation to surface normals. In this case, the colored projective light is reflected according to the shape of the wing.

Implementation: rt/materials/phong

Scene Composition

Scene Construction

We build our scene using Blender. After arranging all models and defining materials with textures, we parsed the exported .obj data with our renderer.

Depth Perception and Viewing Direction

To create the important depth illusion for easy understanding of the scene, we added objects of commonly known sizes, like the remote control and the speakers in the background.

The alignment of the toy plane in relation to the projected movie plane creates the perception of the toy watching the movie.