Applications of Ray Tracing

Ray Tracing in Architecture

"Architecture is the masterly, correct, and magnificent play of masses brought together in light."
                                                                                                -Le Corbusier (Architect and Urbanist 1927)

    When presenting design proposals to clients, it is very important that architects have realistic renderings accompaning their designs.  In the past, architects relied on hand-done drawings created with ink and watercolors.  Unfortunately, it is extremely difficult to produce realistic illumination effects using the traditional rendering methods.  Even many computer aided design (CAD) programs which accuratley model objects are unable to model light.
    Some modeling programs even allow architects to introduce light into a picture, specifying the light's location, orientation, color, and distibution.  These features help designers to create effects such as shadows and specular highlights, however, they still fail to model the physical reality that objects interact  with light.  In order to accurately model the true behavior of light in a given environment, we must consider all of the light in that environment, and acknowledge that real light is reflected, refracted, diffused, and absorbed.
    Architects are primarily interested in creating visually realistic images. Backwards ray tracing, combined with radiosity techniques, is often the most useful method for architectural rendering. Because modeling light is so essential to the field, the development of programs that incorporate ray tracing has been a dream come true for many architects.  Global illumination technology is succeeding in bringing architectural design to life.

Examples of Traditional Architectural Renderings

Examples of Ray Traced Architectural Images
 
 

Ray Tracing in Theater and Television Lighting Design

    Because ray tracing allows visually realistic modeling of light, the technology can be usefully applied in the areas of theater and television lighting.  Without the abilty to model physically correct images, stage lighting setups can take extreme amounts of effort.  Many stage and television productions require hundreds of individual lights that must be positioned, aimed, and filtered.  It is also necessary for lights to be switched, redirected, and dimmed while a production is actually in progress.  Ray tracing allows set and lighting designers, actors, and directors to develop and visualize complex lighting setups months before a production ever opens.

Ray Tracing as a Tool for Engineers

    Ray tracing is capable of considering all of the light in a given environment (termed global illumination).  Global illumination is a physically correct model, which accurately simulates light's behavior in a real physical environment.  This proves to be extremely useful to lighting designers, solar energy researchers, and mechanical engineers.  They can use ray tracing to do much more than  render photorealistic pictures.  Engineers use the technology to predict illumination levels, luminance gradients, and visual performance criteria.  Global illumination is a valuable engineering tool in that it allows us to quantitatively analyze the distribution and directionality of light and  research radiant heat transfer.  This is helping us to progress in everything from lighting and heating rooms more effeciently, to  creating solar energy concentrators for aerospace applications.
 

Ray Tracing in Animation

    Questions surrounding animation have interested computer scientists for several decades.  Advancements in computer graphics including developments in ray tracing have opened up world of possibility in the field.  Traditionally, individual frames of animated works were drawn by hand.  Movement was simulated through  a complex series frame adjustment steps.  There is still a strong sense of nostalgia for traditional methods of animation, however, computer graphics are playing a stronger and stronger role in the process.
    Computer animation is executed on model worlds before they are rendered by a ray tracer. This technique can be highly optimized.
    Ray tracing can be used to add "fancy" effects such as reflection and shadowing that are often difficult  and time consuming for traditional artists to produce. Graphical technology is also capable of rendering photorealistic images that would be nearlt impossible to produce without computerized ray tracing.
    Examples of computer graphics and ray tracing in modern animation include advanced reflection, shadowing, and specularity.

Beauty and the Beast  Aladdin

Toy Story

 


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