Abstract: A method for creating artistic effects for volumetric illumination in a scene is provided. Data representing a scene is received. User input is received, which specifies a target appearance of the scene, including illumination effects that are at least in part non-physically-based. Photon beams representing volumetric illumination in the scene are generated; this step may incorporate user input-based modifications of the photon beams. Shading associated with the photon beams is computed; this step may also incorporate user input-based modifications. Any modifications in the generating or computing steps are derived from the specified target appearance of the scene. Finally, the photon beams are rendered.

Abstract: A method for rendering radiance for a volumetric medium is provided. A photon simulation produces a representation of photon beams in a scene. The photon beams are rendered with respect to a camera viewpoint, by computing an estimated radiance associated with the photon beams. A global radius scaling factor can be applied to obtain different radii for the photon beams. Over multiple applications of these steps, the global radius scaling factor can be decreased, thereby reducing overall error by facilitating convergence. Finally, the renderer can be efficiently implemented on the GPU as a splatting operation, for use in interactive and real-time applications.

Abstract: A plurality of measured sample data points associated with reflectance on a surface of a material is obtained. A non-parametric densely tabulated one-dimensional representation for a plurality of factors in a microfacet model is generated, using the obtained sample data points.

Abstract: Techniques for displaying content using an augmented reality device are described. Embodiments provide a visual scene for display, the visual scene captured using one or more camera devices of the augmented reality device. Embodiments adjust physical display geometry characteristics of the visual scene to correct for optimal projection. Additionally, illumination characteristics of the visual scene are modified based on environmental illumination data to improve realism of the visual scene when it is displayed. Embodiments further adjust display characteristics of the visual scene to improve tone mapping output. The adjusted visual scene is then output for display on the augmented reality device.

Abstract: Techniques are described for designing and manufacturing a refractive surface that produces a desired image when placed over a target image. The refractive lens surface may include a set of lens patches, each of which indexes a region on the source image to refract light from the indexed region to recreate a patch of the target image. And together, the lenses reproduce the target image. In one embodiment, the refractive geometry of the lens surface (i.e., the shape of each lens) is determined by formulating and efficiently determining a solution to an inverse light transport problem. The solution may account for additional constraints imposed by the physical manufacturing procedure. Doing so results in a design for a refractive surface amenable to milling (or other manufacturing process).

Abstract: Methods and systems of joint path importance sampling are provided to construct light paths in participating media. The product of anisotropic phase functions and geometric terms across a sequence of path vertices are considered. A connection subpath is determined to join a light source subpath with a light receiver subpath with multiple intermediate vertices while considering the product of phase functions and geometry terms. A joint probability density function (“PDF”) may be factorized unidirectional or bidirectional. The joint PDF may be factorized into a product of multiple conditional PDFs, each of which corresponds to a sampling routine. Analytic importance sampling may be performed for isotropic scattering, whereas tabulated importance sampling may be performed for anisotropic scattering.

Abstract: The disclosure provides an approach for determining, in 3D rendering, the integrals of visibility-masked spherical functions using visibility silhouettes. For a given shade point, the visibility silhouette for that shade point includes a set of edges from the scene geometry which form the boundaries between visible and invisible regions of a hemisphere having the shade point as its center. For each shade point, a rendering application determines a set of contour edges of scene geometry, the contour edges being a superset of the set of visibility silhouette edges, by querying a 4D dual mesh. The rendering application then evaluates the integral of the visibility-masked spherical function for a given shade point by integrating over segments of discrete u-isolines for which an overlap function indicates that a ray from the shade point would not intersect scene geometry.

Abstract: A method and system for progressively rendering radiance for a volumetric medium is provided. A photon simulation produces a representation of photon beams in a scene. The photon beams are rendered with respect to a camera viewpoint, by computing an estimated radiance associated with the photon beams. A global radius scaling factor is applied to the photon beams. Over multiple iterations of these steps, the global radius scaling factor is progressively decreased, thereby reducing overall error by facilitating convergence. This order can be mixed up. Finally, the renderer can be efficiently implemented on the GPU as a splatting operation, for use in interactive and real-time applications.

Abstract: Projection systems and methods handle images to be viewable on a concave surface, wherein the projected image is modified to account for surface-to-surface reflections due to the concave surface, by determining geometric surface parameters, determining the ideal image, determining a model for reflected light that is a result of surface-to-surface reflections given the ideal image, wherein the model is expressible in closed form, determining a compensation image to compensate for at least some of the surface-to-surface reflections, taking into account at least the ideal image and the reflected light, and combining the compensation image and the ideal image to form a projectable image that can be projected onto a surface having the determined geometric parameters. The surface can be defined by a portion of an interior of a sphere and the reflection of a given pixel can be modeled as a constant over the concave surface.

Abstract: Techniques are described for designing and manufacturing a refractive surface that produces a desired image when placed over a target image. The refractive lens surface may include a set of lens patches, each of which indexes a region on the source image to refract light from the indexed region to recreate a patch of the target image. And together, the lenses reproduce the target image. In one embodiment, the refractive geometry of the lens surface (i.e., the shape of each lens) is determined by formulating and efficiently determining a solution to an inverse light transport problem. The solution may account for additional constraints imposed by the physical manufacturing procedure. Doing so results in a design for a refractive surface amenable to milling (or other manufacturing process).

Abstract: Techniques for displaying content using an augmented reality device are described. Embodiments provide a visual scene for display, the visual scene captured using one or more camera devices of the augmented reality device. Embodiments adjust physical display geometry characteristics of the visual scene to correct for optimal projection. Additionally, illumination characteristics of the visual scene are modified based on environmental illumination data to improve realism of the visual scene when it is displayed. Embodiments further adjust display characteristics of the visual scene to improve tone mapping output. The adjusted visual scene is then output for display on the augmented reality device.

Abstract: A real-time method for rendering soft shadows from lighting environments on dynamic height fields provides for self-shadowing by computing a horizon map for set azimuthal directions with a multiple resolution pyramid on the height field. The multiple resolution pyramid comprises more levels than power of two levels. Visibility is represented by an order-4 spherical harmonic (SH) basis. The method is local, parallel and substantially performance independent of geometric content, and may allow for soft shadows to be rendered in a computer game, for example.

Abstract: General and realtime technique for soft global illumination in low-frequency environmental lighting. The technique accumulates over a relatively few spherical proxies that approximate the light blocking and re-radiating effect of dynamic geometry. Soft shadows are computed by accumulating log visibility vectors for each sphere proxy as seen by each receiver point. Inter-reflections are computed by accumulating vectors representing the proxy's unshadowed radiance when illuminated by the environment. Both vectors capture low-frequency directional dependence using the spherical harmonic basis. Additionally, a new proxy accumulation method splats each proxy to receiver pixels in image space to collect the proxy's contribution to shadowing and indirect lighting. A soft rendering pipeline unifies direct and indirect soft effects with an accumulation methodology that maps entirely to a graphics processing unit and outperforms previous vertex-based methods.