Abstract: In one embodiment, a method includes determining a first time interval for rendering pixel values for a first portion of a display, where the first portion of the display is one of a plurality of portions of the display, accessing a representation of virtual objects in a virtual scene, and determining that the first time interval is insufficient for rendering pixel values for the first portion of the display based on the representation of virtual objects. The method further includes, for each of the portions of the display, determining a current viewpoint of a user, rendering, based on the current viewpoint of the user, pixel values for that portion of the display, and sending the rendered pixel values to be output by the display, where the rendered pixel values for the first portion of the display are rendered based on a simplified representation of virtual objects in the virtual scene.

Abstract: In one embodiment, a method includes, generating rays for casting into an artificial reality scene that includes one or more surfaces to determine whether the one or more surfaces are visible from a viewpoint. An origin and a trajectory of each ray are based on the viewpoint. The method includes applying a geometric transformation to the rays to modify their respective trajectory into the artificial reality scene. The geometric transformation is based on one or more distortion characteristics of a display system. The method includes determining, based on the modified trajectories of the rays, points of intersection of rays with the one or more surfaces in the artificial reality scene. The method includes providing, for display by the display system, color values generated based on the determined points of intersection.

Abstract: In one embodiment, a computing system may access an image to be displayed by a display. The system may determine one or more characteristics associated with a content of the image. The one or more characteristics may include a spatial frequency of the content in a spatial frequency domain. The system may determine a display persistence time period for the display to display the image based on the one or more characteristics associated with the content of the image. The system may configure the display to display the image using the display persistence time period.

Abstract: In one embodiment, a computing system may determine, for a pixel, a sampling location within a texture that comprises a plurality of texels, and based on the sampling location, select a set of texels in the plurality of texels. Each texel in the set of texels may encode a distance field. An interpolated distance field associated with the sampling location may be computed based on the distance fields associated with the set of texels. The interpolated distance field may represent a relative distance between the sampling location and a texture edge. According to a blending proportion based on the interpolated distance field, the computing system may determine a blended color for the sampling location by blending, a first and second color associated with a first side of the edge and a second side of the edge, and output a color for the pixel based on the blended color.

Abstract: In one embodiment, a system may determine a sampling location within a texture with each texel encoding first and second distance fields and first and second color indices. The system may select, based on the sampling location, a set of texels to use to determine a color for the sampling location. The system may compute first and second interpolated distance fields based on, respectively, the first and second distance fields of the set of texels. The system may select, based on the first interpolated distance field, a subset of the set of texels, and select a texel from the subset of texels based on a distance between the texel and the sampling location. The system may select, based on the second interpolated distance filed, a color index from the first and second color indices of the selected texel and use it to determine the color for the sampling location.

Abstract: In one embodiment, a computing system may determine, for a pixel, a sampling location within a texture that comprises a plurality of texels, and based on the sampling location, select a set of texels in the plurality of texels. Each texel in the set of texels may encode a distance field. An interpolated distance field associated with the sampling location may be computed based on the distance fields associated with the set of texels. The interpolated distance field may represent a relative distance between the sampling location and a texture edge. According to a blending proportion based on the interpolated distance field, the computing system may determine a blended color for the sampling location by blending, a first and second color associated with a first side of the edge and a second side of the edge, and output a color for the pixel based on the blended color.

Abstract: In one embodiment, a computing system may receive a number of texels organized into a texel array including a number of sub-arrays. The system may determine a number of texel subsets with the texels in each subset having a same position within their respective sub-arrays. The system may store the texel subsets into a number of buffer blocks, respectively, with each buffer block storing one texel subset. The system may retrieve a sampling texel array from the buffer blocks for parallelly determining pixel values of a number of sampling points. Each texel of the sampling texel array may be retrieved from a different buffer block.

Abstract: In one embodiment, a method includes accessing a first distortion definition for a first color component and a second distortion definition for a second color component; generating, for a pixel, a first ray for the first color component of the pixel and a second ray for the second component of the pixel; defining trajectories for the first and second rays using the first and second distortion definitions, respectively; casting, from a viewpoint in a 3D space, the first and second rays into the 3D space using the defined trajectories; computing, for the first and second rays, a first intersection location and a second intersection location with one or more objects in the 3D space; and determining a color value for the pixel based on the first and second intersection locations.

Abstract: In one embodiment, an apparatus, coupled to a computing system, may include a first-level of data bus comprising first-level data lines. The apparatus may include second-level data buses each including second-level data lines. Each second-level data bus may be coupled to a memory unit. The second-level data lines of each second-level data bus may correspond to a subset of the first-level data lines. The apparatus may include third-level data buses each including third-level data lines. Each third-level data bus may be coupled to a sub-level memory unit. The third-level data lines of each third-level data bus may correspond to a subset of the second-level data lines of a second-level data bus along a structural hierarchy. The apparatus may be configured to allow the computing system to load a data block from the first-level data lines to sub-level memory units through the third-level data buses excluding multiplexing operations.

Abstract: In an embodiment, a headset display device includes a central processor and multiple projector integrated circuits each coupled to the central processor and configured to process image data. Each projector integrated circuit includes multiple first integrated circuits, each including a light emitter array. Each projector integrated circuit includes a second integrated circuit coupled to the multiple first integrated circuits. The second integrated circuit includes a graphics processor configured to generate transformed image data correcting for geometrical or brightness distortions and (2) is configured to provide the transformed image data to the multiple first integrated circuits for display.

Abstract: In one embodiment, a computing system may access a first image that is generated at a first frame rate. The system may determine whether a change of a user viewpoint with respect to one or more display contents satisfies a threshold criterion. The system may select an operation mode from a first operation mode and a second operation mode based on the determination whether the change of the user viewpoint satisfies the threshold criterion. The system may generate a number of second images at a second frame rate higher than the first frame rate. When the selected operation mode is the first operation mode, the second images may be generated using a resampling process. When the selected operation mode is the second operation mode, the second images may be generated by transforming one or more previously generated second images that are generated based on the first image.

Abstract: In one embodiment, a method includes accessing a distortion definition for a first color component of a collection of pixels; casting, from a viewpoint in a three-dimensional (3D) space, a first bundle of rays for the first color component in accordance with the distortion definition; computing a first set of intersection locations between the cast first bundle of rays and an object in the 3D space; determining that a difference between distortions of the first color component and a second color component is greater than a first predetermined threshold and less than a second predetermined threshold; determining the second set of intersection locations on the object for the second color component based on shifting the first set of intersection locations; and determining color values for the collection of pixels based on the first and second sets of intersection locations.

Abstract: In one embodiment, a method includes accessing a distortion mesh defined in a 3D space by a plurality of mesh coordinates that are respectively associated with a plurality of predetermined points in a screen representation, where each mesh coordinate specifies a trajectory for a ray cast from the associated predetermined point into the 3D space; determining a sampling point within the screen representation; selecting a set of mesh coordinates from the plurality of mesh coordinates based on proximities between the sampling point and the predetermined points associated with the set of mesh coordinates; computing a sampling trajectory for the sampling point based on the selected set of mesh coordinates; casting a ray into the 3D space using the sampling trajectory; computing an intersection location between the cast ray and an object in the 3D space; and determining a color value for the sampling point based on the intersection location.

Abstract: In one embodiment, a computing system may write pixel values into a buffer in a tile order. Each writing operation may write a block of pixel values into two memory units. The first memory unit may receive a first half of the block of pixel values. The second memory unit may receive a second half of the block of the pixel values. The system may read a subset of pixel values from the buffer in a pixel row order. Each reading operation may read a second block of pixel values from the two memory units of the buffer. The first memory unit may provide a first half of the second block of pixel values. The second memory unit may provide a second half of the second block of pixel values. The system may output the subset of pixel values read from the buffer via an output data bus.

Abstract: Systems and methods may provide for receiving a pixel shader and sending the pixel shader to shader bypass hardware if the pixel shader and a render target associated with the pixel shader satisfy a simplicity condition. In one example, the shader bypass hardware is dedicated to pixel shaders and associated render targets that satisfy the simplicity condition.

Abstract: In one embodiment, a method for generating subframes may include accessing a rendered frame depicting a virtual scene from a first viewpoint of a user. The rendered frame may be generated based on at least one 3D model of an object in the virtual scene. A computing system may generate plurality of surfaces based on the rendered frame. Each surface may be positioned within a 3D space and comprises visual information. The system may determine a second viewpoint of the user in the 3D space and determine a visibility of the plurality of surfaces from the second viewpoint. The system may then render a subframe depicting the virtual scene from the second viewpoint based on the visual information and determined visibility of the plurality of surfaces.

Abstract: In one embodiment, a computing system may determine a focus point of a viewer based on received sensor data. The system may determine, for a current frame, a first viewing region encompassing a focus point of the viewer and a second view region excluding the first viewing region. The system may determine, for the current frame, color values for the first viewing region using respective first sampling resolutions, and color values for the second viewing region using respective second sampling resolutions. At least one second sampling resolution may be lower than a corresponding first sampling resolution associated with a same color channel. At least two of the second sampling resolutions for the color channels of the second viewing region may be different from each other. The system may output the color values for the first viewing region and the second viewing region of the current frame for display.

Abstract: In one embodiment, a method includes, by a computing system, determining a sample point within a texture. The sample point corresponds to a specified output position in a display system. The method includes accessing texels in the texture that are used for determining properties of the sample point. Each identified texel includes a color and a transparency level. The method includes determining an interpolation optimization by comparing the colors and transparency levels of the identified texels. The method includes determining, according to the determined interpolation optimization, a pixel color and a pixel transparency level for the sample point using the identified texels. At least one of the pixel color or the pixel transparency level is determined by copying the colors or transparency levels of the texels, respectively, without performing interpolation. The method includes providing the determined pixel color and the determined pixel transparency level for the sample point for display.

Abstract: In one embodiment, a method includes accessing a first distortion definition for a first color component of a collection of pixels and a second distortion definition for a second color component of the collection of pixels; casting, from a viewpoint in a 3D space, a first bundle of rays for the first color component in accordance with the first distortion definition; computing a first set of intersection locations between the cast first bundle of rays and an object in the 3D space; determining, based on the first and second distortion definitions, that a difference between distortions of the first and second color components satisfies a predetermined threshold; estimating, using the first set of intersection locations, a second set of intersection locations on the object for the second color component; and determining color values for the collection of pixels based on the first and second sets of intersection locations.

Abstract: In one embodiment, a method includes generating rays for casting into an artificial reality scene that includes one or more surfaces to determine whether the one or more surfaces are visible from a viewpoint. The method includes determining points of intersection between the rays and the one or more surfaces. The method includes determining, based on the points of intersection, color values corresponding to output positions of a display system. The method includes accessing brightness adjustment data corresponding to the output positions of the display system. The brightness adjustment data are determined based on one or more characteristics of the display system. The method includes applying one or more brightness adjustments to the color values based on the brightness adjustment data. The method includes providing the color values for display at the corresponding output positions of the display system.