86 results about "Bounding volume hierarchy" patented technology

The invention discloses an apparatus and method for converting compressed geometries into accelerated data structures. An apparatus and method for transforming lossy compressed geometries into a bounding volume hierarchy. For example, one embodiment of a method includes constructing a bounding volume hierarchy (BVH) based on a compressed hierarchy (LOD) structure formed from iteratively merged geometric primitive cluster pairs, where constructing the BVH includes traversing the compressed hierarchy (LOD) structure, to select a subset of the cluster on one or more levels of a compressed hierarchy (LOD) structure based on the current cone of view; decompressing each cluster and constructing a per-cluster BVH on the primitive of each cluster, wherein each per-cluster BVH comprises a per-cluster BVH root node; and fusing the per-cluster BVH root nodes to form a BVH, the BVH being used to efficiently ray trace all decompressed geometric primitives in the scene.

A method performed by a graphics processor searches for a candidate reinsertion for each of a plurality of input nodes of a current bounding volume hierarchy (BVH) which would move the input node from an old parent to a new parent, and which would reduce an expected computational cost of searching the BVH for a ray intersection; and performs a first update to update the current BVH with one or more selected reinsertions from among the candidates. The selection comprises a conflict check to determine whether any group of the candidates would affect a same part of the current BVH, and if so selecting only one of the group to include in the first update. At least one of the iterations further comprises, after the first update, performing a second update within the same iteration to update the current BVH with another of said group.

Apparatus and method for using multiple bounds to bound BVH child nodes. For example, one embodiment of an apparatus comprises: traversal hardware logic to traverse rays through a bounding volume hierarchy (BVH); and BVH construction circuitry to evaluate nodes of an N-wide BVH, the BVH construction circuitry to generate a union of multiple bounding boxes for one or more child nodes of the BVH to produce one or more corresponding union-bounded child nodes, wherein a node of the BVH stores N bounding boxes and each corresponding child node of the BVH is bounded by 0 to N of the bounding boxes; the traversal hardware logic to traverse a ray through the N-wide BVH and to determine a hit with respect to each union-bounded child node if any of the bounding boxes associated with the union-bounded child node are hit by the ray.

Apparatus and method for manageable fragmented acceleration structures. For example, one embodiment of an apparatus comprises: acceleration structure construction logic to build an acceleration structure (AS) including a multi-level linkage hierarchy with different types of AS fragments, the different types of AS fragments including a first type of AS fragments with leaves, a second type of AS fragments including AS linkages, and a third type of AS fragment including both leaves and AS linkages, wherein to construct an AS fragment, the acceleration structure construction logic is to: evaluate a plurality of primitive references, determine whether each primitive reference indicates a primitive or an AS fragment, and if the primitive reference indicates an AS fragment, then encode a pointer or offset directly or indirectly into a bounding volume hierarchy (BVH) of the AS fragment; and traversal hardware logic to traverse a ray through the AS.

A technique for performing ray tracing operations is provided. The technique includes identifying triangles to include in a compressed triangle block; storing data common to the identified triangles as common data of the compressed triangle block; and storing data unique to the identified triangles as unique data of the compressed triangle block.

A technique for performing ray tracing operations is provided. The technique includes arriving at a bounding box of a bounding volume hierarchy (“BVH”) having an orientation defined based on a platonic solid; testing a ray for intersection with the bounding box; and continuing traversal of the BVH based on results of the testing.

Systems and methods for faster BVH building that requires repeated sorting and partitioning of are described. Specific hardware circuitries are programmed to sort partitioned data and make reductions for each partition. The hardware units perform the initial sorting along a split axis and calculation of bounding box extents. The solutions presented herein improve performance of BVH builds, especially for cases where the geometry is comprised of many small BVH treelets. The most expensive processing steps in BVH construction are delegated to hardware thereby minimizing memory access latencies and increasing overall system efficiencies.

Systems and techniques are provided for accelerated ray tracing. For instance, a process can include obtaining a hierarchical acceleration data structure that includes a plurality of primitives of a scene object and obtaining a respective information value associated with each primitive included in the plurality of primitives. A sort order can be determined for two or more nodes included in a same level of the hierarchical acceleration data structure at least in part by sorting the two or more nodes based on a respective sorting parameter value determined for each respective node of the two or more nodes. Each respective sorting parameter value can be determined based on at least one information value associated with one or more primitives included in a sub-tree of each respective node of the two or more nodes. The hierarchical acceleration data structure can be traversed using the sort order.

A technique for performing a ray tracing operation is provided. The technique includes identifying triangles to be included in a compressed triangular block; storing data common to the identified triangles as common data for the compressed triangular block; and storing data unique to the identified triangle as unique data for the compressed triangle block.

Techniques for constructing a bounding volume hierarchy are disclosed that include refining a candidate box node based on a resolution to generate a plurality of cells for the candidate box node, identifying a plurality of nodes of a triangle set collection that fall within the cell, generating a plurality of candidate splits based on the plurality of nodes, selecting the candidate splits based on a selection criterion to obtain selected candidate splits, and generating child box nodes for the box node of the bounding volume hierarchy being constructed based on the selected candidate splits.

This disclosure provides systems, devices, apparatus, and methods, including computer programs encoded on storage media, for traversing a low-resolution BVH. A processor may obtain a first indication of a low-resolution BVH that includes a set of conservative candidate nodes that are associated with corresponding internal nodes of a full-resolution BVH. The processor may traverse the low-resolution BVH by (a) determining whether a ray intersects a primitive leaf of a conservative candidate node of the set of conservative candidate nodes in response to a first determination that the ray intersects the conservative candidate node and (b) traversing an internal node of the full-resolution BVH that corresponds with the conservative candidate node in response to a second determination that the ray does not intersect the primitive leaf. The processor may output a second indication of a ray trace hit or a ray trace miss based the traversal.

In a graphics processor, optimising a bounding volume hierarchy (BVH) acceleration structure representing 3D regions of space in a modelled environment for ray tracing. The BVH is a tree with leaf nod

Apparatuses and methods for manageable segmented acceleration structures are disclosed. For example, one embodiment of an apparatus includes acceleration structure construction logic to construct an AS including a multi-level link hierarchy having different types of acceleration structure (AS) fragments, the different types of AS fragments including a first type of AS fragments having leaves, a second type of AS fragments including AS links, and a third type of AS fragments including both leaves and AS links, wherein in order to construct the AS fragment, the acceleration structure construction logic is to evaluate a plurality of primitive references, determine whether each primitive reference indicates a primitive or an AS fragment, and encode a pointer or offset directly or indirectly into a boundary volume hierarchy (BVH) of the AS fragment if the primitive reference indicates the AS fragment; and traversal hardware logic to traverse the rays through the AS.

Techniques are disclosed relating to ray tracing, e.g., in graphics processors. Ray tracing embodiments may utilize a bounding volume hierarchy (BVH) acceleration data structure (ADS) that includes a hierarchy of bounding volumes. A graphics processor may traverse the ADS, testing for intersections with bounding volumes, to determine which primitives to test for a given ray. Some nodes may be transform nodes (e.g., instance nodes) that correspond to a ray transform before further traversal. In disclosed embodiment, one or more levels below the transform node may be reverse transformed and included above the transform node. This may advantageously avoid a ray transform operation for rays that would not have hit in the first one or more levels of the transform sub-tree.

Techniques herein involve building bounding volume hierarchies for ray tracing using neural networks. Bottom-up BVH building techniques include nearest neighbor search operations and tree construction operations. The nearest neighbor search operations evaluate a set of candidate nodes that do not have any parents to identify nearest neighbor pairs and the tree construction operations “combine” the nearest neighbor pairs by generating new nodes that are parents of the nodes of the pairs. The nearest neighbor search is an expensive operation as it generally considers all possible combinations of the set to select one considered “best.” A neural network model is thus proposed herein which can perform this nearest neighbor search in a more efficient manner. Specifically, the neural network model accepts, as input, information characterizing the nodes of a set for which a search is performed and provides, as output, information characterizing the nearest neighbor pairs found for the set.

A method and system for traversing a bounding volume hierarchy (BVH) structure associated with a given 3D scene using a ray tracing algorithm are provided. The method comprises: determining an escape probability value for a given node of the BVH structure of a given ray traversing the given node without reflecting off any mesh element contained therein; propagating a ray in the given 3D scene that intersects the respective bounding volume of the given node; in response to determining that the ray is to traverse the respective bounding volume, determining whether the ray is to traverse or to reflect off an other respective bounding volume; and in response to determining that the ray is to reflect off the respective bounding volume: rendering a mesh element contained in the respective bounding volume of the given BVH node.

A method and system for traversing a bounding volume hierarchy (BVH) structure associated with a given 3D scene using a ray tracing algorithm are provided. The method comprises: determining an escape probability value for a given node of the BVH structure of a given ray traversing the given node without reflecting off any mesh element contained therein; propagating a ray in the given 3D scene that intersects the respective bounding volume of the given node; in response to determining that the ray is to traverse the respective bounding volume, determining whether the ray is to traverse or to reflect off an other respective bounding volume; and in response to determining that the ray is to reflect off the respective bounding volume: rendering a mesh element contained in the respective bounding volume of the given BVH node.

Apparatus and method for a BVH with oriented boundaries using quantized shared orientations. For example, one embodiment of an apparatus comprises: traversal hardware logic for traversing rays through a bounding volume hierarchy (BVH); and BVH construction circuitry for generating a BVH with one or more oriented bounding boxes (OBBs), wherein the BVH construction circuitry projects a geometry of one or more child nodes along one or more orientation directions to determine corresponding upper and lower bounds; wherein the traversal hardware logic comprises OBB processing logic for: projecting a ray along the one or more orientation directions;in response, determining beam-plane intersection distances to one or more near and far boundary planes corresponding to the orientation directions; and determining a hit or miss based on the beam-plane intersection distances to the near and far boundary planes.

An implementation comprises traversing a bounding volume hierarchy for each ray of a plurality of rays concurrently using a plurality of execution items. In response to determining that a first execution item of the plurality of execution items is finished traversing the bounding volume hierarchy for a first ray of the plurality rays, the embodiment causes the first execution item to traverse the bounding volume hierarchy for a second ray of the plurality of rays while a second execution item of the plurality of execution items traverses the bounding volume hierarchy for the second ray. And the embodiment comprises initiating side-effects with the first and second execution items in an order indicated by the bounding volume hierarchy.

A graphics processor includes circuitry configured to generate a bounding volume hierarchy (BVH) data structure for a graphics scene to be rendered. The BVH includes a leaf node that includes: node data that specifies quantization frame data for quantized primitive children of the leaf node, a quantized primitive block that includes quantized vertex components of the primitive children, and a vertex residual block that includes additional vertex data for the primitive children. The vertex residual block may not include redundant data with the quantized primitive block and the quantized primitive block and vertex residual block may include, for the primitive children, sufficient data to reconstruct an original-precision representation of their vertices. The circuitry may traverse the BVH to perform ray tracing operations during render of the graphics scene, including to perform one or more ray primitive intersect tests based on the quantized primitive block and the vertex residual block.

Embodiments of the present disclosure relate to a method, an electronic device and a computer storage medium for compressing a bounding volume hierarchy, and relate to the field of information processing. According to the method, a node in a bounding volume hierarchy and a plurality of child nodes of the node are acquired; a maximum number difference between a plurality of primitives included in the plurality of child nodes is determined; if it is determined that the maximum number difference is less than or equal to a representation range of a primitive number difference field in a first compressed node format, the node and the plurality of child nodes are compressed based on the first compressed node format; and if it is determined that the maximum number difference is greater than the representation range of the primitive number difference field in the first compressed node format, the node and the plurality of child nodes are compressed based on a second compressed node format, the second compressed node format having a length greater than a length of the first compressed node format. Thus, the bounding volume hierarchy can be efficiently compressed.

Apparatus and method for box-box testing. For example, one embodiment of a processor comprises: a bounding volume hierarchy (BVH) generator to construct a BVH comprising a plurality of hierarchically arranged BVH nodes; traversal circuitry to traverse query boxes through the BVH, the traversal circuitry to read a BVH node from a top of a BVH node stack and to read a query box from a local storage or memory, the traversal circuitry further comprising: box-box testing circuitry and / or logic to compare maximum and minimum X, Y, and Z coordinates of the BVH node and the query box and to generate an overlap indication if overlap is detected for each of the X, Y, and Z dimensions; distance determination circuitry and / or logic to generate a distance value representing an extent of overlap between the BVH node and the query box; and sorting circuitry and / or logic to sort the BVH node within a set of one or more additional BVH nodes based on the distance value.

Techniques herein involve generating a bounding volume hierarchy in a fast and accurate manner. The techniques begin with a quickly built initial BVH and traverse that initial BVH in a bottom-up manner to generate a new BVH. The algorithm begins at the bottom level, setting the bottom-most primitive nodes as nodes in the new BVH and follows the initial BVH up, collecting uncombined nodes from lower levels to higher nodes. When the algorithm has collected a threshold number of such nodes at a node of the initial BVH, the algorithm builds a new subtree for that node by combining the threshold number of such nodes, and adds that new subtree to the new BVH. This algorithm is efficiently parallelizable by immediately switching from the traversal phase to the combining phase and using all work-items of a wavefront for such combining.

The invention relates to a method and system for constructing a ray tracing acceleration structure. A computer-implemented method of creating a bounding volume hierarchy, BVH, for a model is disclosed. The model is defined with respect to a local coordinate system of the model. The method comprises defining a BVH branch node within the model, establishing a plurality of local transformation matrices for the BVH, and for each BVH branch node, determining a first bounding volume and associating the branch node with one of the plurality of local transformation matrices that maps between the first bounding volume and a second bounding volume in the local coordinate system.

A fused bounding volume hierarchy, which is a combination of a base bounding volume hierarchy and one or more non-base bounding volume hierarchies, is generated. For each non-base bounding volume hierarchy, multiple subtrees in the non-base bounding volume hierarchy that include less than a threshold number of child nodes are identified. Each of these subtrees is then fused with the base bounding volume hierarchy at one of the nodes of the base bounding volume hierarchy, and an identifier of the level of detail for the non-base bounding volume hierarchy is included in the node. When displaying a scene or image, for a particular portion of the scene or image the level of detail to use is identified. The fused bounding volume hierarchy is traversed and the geometric objects in the nodes of the fused bounding volume hierarchy corresponding to the identified level of detail are displayed.

Aspects of the disclosure are directed to ray tracing. In accordance with one aspect, the disclosure includes determining if a node state is a leaf node, wherein the node state is at a current node of a bounding volume hierarchy (BVH); determining a ray intersection of a first child node In one example, from the current node using the ray hit information and a traversal stack. In one example, the method further includes updating a state information about a second child node and subsequent child nodes using the traversal stack.

The present invention provides a three-dimensional model scene rendering method, which includes: creating a hierarchical bounding volume hierarchy (BVH) structure tree; extracting model data to obtain all model component objects; traversing all building component objects, creating a minimum bounding box for each building component object, organizing and arranging the minimum bounding boxes with the same component type together and creating a new minimum bounding box to enclose them until all components in the scene are within a large minimum bounding circle; using a frustum culling algorithm to eliminate invalid components, and performing three-dimensional engine rendering on the BVH tree after component culling. The method of the present invention greatly improves the rendering efficiency of the three-dimensional engine for models, and effectively enhances the user experience during the use of the three-dimensional platform.

A technique for performing a ray tracing operation is provided. The technique includes traversing to a pre-filtering node for a tested ray intersecting a geometry associated with the bounding volume hierarchy, the pre-filtering node including information of triangles for filtering out leaf nodes of the bounding volume hierarchy; evaluating quantized rays corresponding to the rays for the quantized triangles of the pre-filtered nodes to filter out one or more triangles of the leaf nodes without consideration; and testing unfiltered triangles of the leaf nodes and not testing filtered triangles of the leaf nodes.

A technique for building a bounding volume hierarchy is disclosed. The technique includes for a subject node, selecting a dimension along which to perform a split to form child nodes of the subject node; assigning primitives of the subject node to the child nodes; and updating bounds for the child nodes in a next split dimension and not in the other dimensions.

In a graphics processor, optimising a bounding volume hierarchy (BVH) acceleration structure representing 3D regions of space in a modelled environment for ray tracing. The BVH is a tree with leaf nod