169 results about "Viewing frustum" patented technology

A method for processing interactive user control with a scene of a video clip is provided. The method initiates with identifying a head of a user that is to interact with the scene of the video clip. Then, the identified head of the user is tracked during display of the video clip, where the tracking enables detection of a change in position of the head of the user. Next, a view-frustum is adjusted in accordance with the change in position of the head of the user. A computer readable media, a computing device and a system for enabling interactive user control for defining a visible volume being displayed are also included.

A system providing three-dimensional visual navigation for a mobile unit includes a location calculation unit for calculating an instantaneous position of the mobile unit, a viewpoint control unit for determining a viewing frustum from the instantaneous position, a scenegraph manager in communication with at least one geo-database to obtain geographic object data associated with the viewing frustum and generating a scenegraph organizing the geographic object data, and a scenegraph renderer which graphically renders the scenegraph in real time. To enhance depiction, a method for blending images of different resolutions in the scenegraph reduces abrupt changes as the mobile unit moves relative to the depicted geographic objects. Data structures for storage and run-time access of information regarding the geographic object data permit on-demand loading of the data based on the viewing frustum and allow the navigational system to dynamically load, on-demand, only those objects that are visible to the user.

In an exemplary embodiment, a computer-implemented method determines a set of mesh polygons or fragments of the mesh polygons visible from a navigation cell. The method includes determining a composite view frustum containing predetermined view frusta and determining mesh polygons contained in the composite view frustum. The method includes determining at least one supporting polygon between the navigation cell and the contained mesh polygons. The method further includes constructing at least one wedge from the at least one supporting polygon, the at least one wedge extending away from the navigation cell beyond at least the contained mesh polygons. The method includes determining one or more intersections of the at least one wedge with the contained mesh polygons. The method also includes determining the set of the contained mesh polygons or fragments of the contained mesh polygons visible from the navigation cell using the determined one or more intersections.

Embodiments presented herein provide techniques for creating and simplifying a cell and portal graph. The simplified cell and portal graph may be used to make a conservative determination of whether an element of geometry is visible for a given view frustum (and therefore needs to be rendered). That is, the simplified cell and portal graph retains the encoded visibility for given set of geometry. The simplified cell and portal graph provides a “conservative” determination of visibility as it may indicate that some objects are visible that are not (resulting in unneeded rendering), but not the other way around. Further, this approach allows cell and portal graphs to be generated dynamically, allowing the cell and portal graphs to be used for scenes where the geometry can change (e.g., as 3D world of a video game).

In one embodiment, a movie set includes a motion-picture camera and a visible-talent tracking system having several elements. Based on the camera's characteristics, items in a portion of the movie set called the view frustum will appear in focus in the film. The camera and a camera-tracking system provide camera-location, orientation, and settings information to a culling processor. The culling processor delineates the location and dimensions of the view frustum based on the received camera information. Wireless tags are attached to talent on set. A tag-locating system tracks the real-time respective locations of the wireless tags and provides real-time spatial information regarding the tags to the culling processor, which determines which tags, if any, are considered to be within the view frustum, and provides information associated with the intra-frustum tags to a track recorder for recording along with the corresponding film frames. That information is variously used after editing.

The invention relates to a large-scale virtual crowd real-time rendering method, which comprises the following steps of: 1, introducing the conventional grid model and extracting geometric information and animation information of the model; 2, performing octree space subdivision on the model, wherein approximate description of a part of the model related to geometric size of each node is stored in the node; 3, performing point sampling on the surface of the part of the model included by each node; 4, processing and modeling a sample point, wherein the step comprises the sub-steps of calculating sample point information by interpolation, selecting sample point animation information, oversampling and removing redundancy and the like; 5, establishing model sampling data of three-layer LOD (Levels of Detail) according to specified parameters; 6, performing view frustum culling accelerated by a GPU (Graphic Processing Unit) on a virtual crowd in a large-scale scene during the real-time rendering; 7, performing an LOD strategy accelerated by the GPU on the cuffing result, wherein the step comprises the sub-steps of selecting role LOD and ordering LOD; and 8, sequentially performing GPU skin-skeleton animation based instancing rendering on the role of each layer of LOD level. By adopting the method, quick real-time rendering of a large-scale virtual crowd can be realized.

The present invention relates to an apparatus and method for designing a display for user interaction. The proposed apparatus includes an input unit for receiving physical information of a user and a condition depending on a working environment. A space selection unit selects an optimal near-body work space corresponding to the condition received by the input unit. A space search unit calculates an overlapping area between a viewing frustum space, defined by a relationship between a gaze of the user and an optical system of a display enabling a 3D image to be displayed, and the optimal near-body work space selected by the space selection unit. A location selection unit selects a location of a virtual screen based on results of calculation. An optical system production unit produces an optical system in which the virtual screen is located at the location selected by the location selection unit.

A decompression unit is configured to partially decompress a compressed image formed by compressed tiles. Each compressed tiles correspond to a tile of the uncompressed image. The decompression unit selects a subset of relevant tiles, which are visible in a view window or a view frustum. Specifically, the decompression unit includes a tile selector to select the relevant tile and a tile decompressor to decompress the relevant tiles. By decompressing only a subset of the compressed tiles, the decompression unit reduces the processing time required to generate the contents of the view window.

The invention discloses a method for mass model data dynamic scheduling and real-time asynchronous loading under virtual reality. The method includes the following steps of firstly, preprocessing 3D model scene data, secondly, cutting and partitioning a whole model scene, thirdly, conducting multithreading parallel distribution loading and fourthly, clipping a view cone. Based on a view cone clipping algorithm for acquiring the point of intersection of the view cone and a topographic region, real-time clipping based on the topographic region in dynamic scheduling is achieved, by the adoption of a multithreading processing mechanism of a model data partitioning scheduling and rending pipeline, a dynamic scheduling and drawing pipeline and a data processing scheduling pipeline between different mediums can be asynchronously loaded, and therefore dynamic balance of loading and performance efficiency of the mass scene model data is achieved in the hardware environment with a limited memory, a limited processor and the like.

A distributed clipping scheme is provided, view frustum culling is distributed in several places in a graphics processing pipeline to simplify hardware implementation and improve performance. In general, many 3D objects are outside viewing frustum. In one embodiment, clipping is performed on these objects with a simple algorithm in the PA module, such as near Z clipping, trivial rejection and trivial acceptance. In one embodiment, the SE and RA modules perform the rest of clipping, such as X, Y and far Z clipping. In one embodiment, the SE module performs clipping by way of computing a initial point of rasterization. In one embodiment, the RA module performs clipping by way of conducting the rendering step of the rasterization process. This approach distributes the complexity in the graphics processing pipeline and makes the design simpler and faster, therefore design complexity, cost and performance may all be improved in hardware implementation.

Embodiments allow access to geographic data objects on a per-object basis. A client may send a plurality of requests for geographic data to display within a view frustum. Map data may include a layer with a plurality of assets. Each request may be authenticated by an access control filter, which determines whether the user is authorized to view the data requested.

A display processing system for providing video signals for displaying an image is provided. The display processing system comprises input channels for receiving a plurality of component images, each component image being a portion of the complete image for display, the image data of each component image being defined by a view frustum having a clipping plane, and a combiner for combining the image data of the component images. According to the present invention, at least two clipping planes of two of the view frustums are non-coplanar. Such display processing system corrects for the defect of driving angular resolution to the edges of the field of view of a display system, in particular for large field-of-view display systems, and balances the overall system angular resolution by allowing each image generator channel to render to an optimal view frustum for its portion of the complete image.

The invention provides a shielding removing method and device and computer equipment. The method comprises the following steps that when a shielded object in a current frame of image needs to be determined, a current frame image is drawn, the prediction depth map matched with the current viewpoint parameter can be directly selected from a pre-stored prediction depth map and be taken as a target depth map of the current frame image; the target depth map is utilized to quickly and accurately determine the shielding removal result of the object in the current frame of image; the depth map under the current view frustum does not need to be drawn in the current frame, the waiting time for obtaining the depth map corresponding to the current frame image is greatly shortened, the efficiency of judging the shielding of the object in the image is improved, and due to the mode, the shielding rejection operation cost is reduced, so that the method can be suitable for a mobile platform with poor computing power.

The presnent invention provided a 3D image processing apparatus and method. A 3D image processing apparatus first generates a combined view volume that contains view volumes set respectively by a plurality of real cameras, based on a single temporary camera placed in a virtual 3D space. Then, this apparatus performs skewing transformation on the combined view volume so as to acquire view volumes for each of the plurality of real cameras. Finally, two view volumes acquired for the each of the plurality of real cameras are projected on a projection plane so as to produce 2D images having parallax. Using the temporary camera alone, the 2D images serving as base points for a parallax image can be produced by acquiring the view volumes for the each of the plurality of real cameras. As a result, a processing for actually placing the real cameras can be skipped, so that a high-speed processing as a whole can be realized.

A present novel and non-trivial system, device, and method for generating object symbology are disclosed. A system may be comprised one or more aircraft systems and a cockpit display system comprised of a system configuration file, a plurality of definition files, and a windows generator (“WG”). The WG may be configured to perform initialization and run-time operations. The initialization operation may be comprised of retrieving a system configuration file; retrieving a first definition file comprised of a first layer; and retrieving one or more second definition files comprised of one or more second layers. The run-time operation may be comprised of receiving a first-layer widget data set; receiving one or more second-layer widget data sets; determining the screen position of each object located within a view frustum; and generating a pixel data set in response to the determination.

The invention discloses a method for converting a virtual 3D (Three-Dimensional) scene into a 3D view. The method can be used for converting any virtual 3D scene in OpenGL into a three-dimensional view by the following steps of: rotating and translating a world coordinate system, wherein an observation point is taken as the original point of a new coordinate system, and a connecting line between the central position of viewpoints and the observation point serves as an axis-Z positive axis; determining a rotating angle and a translating distance according to the central position of the viewpoints and the coordinate of the observation point; determining the shear mapping angle of each viewpoint according to the central position of the viewpoints and the coordinate of each viewpoint to generate a corresponding shear mapping matrix, performing right-handed multiplication on a model view matrix of each viewpoint, and projecting to obtain corresponding image data of each viewpoint; and adjusting the coordinate of the 3D scene, the horizontal resolution of the view, the size of a view frustum and the positions of the viewpoints according to a constraint condition of a parallax error and 3D effect experience to improve the 3D effect of the 3D view. Shear transformation and parameter adjustment are inserted in an OpenGL processing flow, so that the problems of unremarkable 3D effect and the presence of vertical parallax are solved, and an optimal 3D effect is achieved.

Vertices defining a graphics primitive are converted into homogeneous space and clipped against a single clipping plane, the w=0 plane, to produce a clipped graphics primitive having vertices including w coordinates that are greater than or equal to zero. Rasterizing a graphics primitive having a vertex with a w coordinates that is greater than or equal to zero is less complex than rasterizing a graphics primitive having a vertex with a w coordinate that is less than zero. Clipping against the w=0 plane is less complex than conventional clipping since conventional clipping may require that the graphics primitive be clipped against each of the six faces of the viewing frustum to produce a clipped graphics primitive.

The invention discloses a simple calculation method of target laser scattering characteristics under local irradiation, and belongs to the technical field of target detection, recognition, and stealth. By modifying the parameters of view-frustum, the simple calculation of scattering cross-section of a target laser radar under local irradiation can be realized. The method comprises the following steps: at first, obtaining the bidirectional reflectance distribution function of a target surface material; establishing a geometric model of a complicated target; reading the target geometric model file, according to the size and position of an irritation laser spot, setting the parameters of view-frustum; calling an OpenGL function to carry out target rendering and blanking to realize real-time display of a target under local irradiation; and finally obtaining each parameter of a target laser radar scattering cross-section calculation formula to complete the target laser radar scattering cross-section imitation calculation under local irradiation. Compared with the conventional algorithms, the adopted algorithm is easy to operate and is flexible; the size and irritation position of the irritation laser spot can be easily modified; and the target laser radar scattering cross-section imitation calculation can be realized under laser overall/local irradiation.