Abstract: A hierarchy is a multi-level linked structure of nodes, wherein the hierarchy represents data relating to a set of one or more items to be processed. Where there are multiple input hierarchies, it may improve the efficiency of the processing of the items to merge the input hierarchies to form a merged hierarchy. The hierarchies are merged by identifying two or more sub-hierarchies within the input hierarchies which are to be merged, and determining one or more nodes of the merged hierarchy which reference nodes of the identified sub-hierarchies. The determined nodes of the merged hierarchy are stored and indications of the references between the determined nodes of the merged hierarchy and the referenced nodes of the identified sub-hierarchies are also stored. In this way, the merged hierarchy is formed for use in processing the items.

Abstract: Systems and methods for producing an acceleration structure provide for subdividing a 3-D scene into a plurality of volumetric portions, which have different sizes, each being addressable using a multipart address indicating a location and a relative size of each volumetric portion. A stream of primitives is processed by characterizing each according to one or more criteria, selecting a relative size of volumetric portions for use in bounding the primitive, and finding a set of volumetric portions of that relative size which bound the primitive. A primitive ID is stored in each location of a cache associated with each volumetric portion of the set of volumetric portions. A cache location is selected for eviction, responsive to each cache eviction decision made during the processing. An element of an acceleration structure according to the contents of the evicted cache location is generated, responsive to the evicted cache location.

Abstract: Ray tracing units, processing modules and methods are described for generating one or more reduced acceleration structures to be used for intersection testing in a ray tracing system for processing a 3D scene. Nodes of the reduced acceleration structure(s) are determined, wherein a reduced acceleration structure represents a subset of the 3D scene. The reduced acceleration structure(s) are stored for use in intersection testing. Since the reduced acceleration structures represent a subset of the scene (rather than the whole scene) the memory usage for storing the acceleration structure is reduced, and the latency in the traversal of the acceleration structure is reduced.

Abstract: In some aspects, systems and methods provide for forming groupings of a plurality of independently-specified computation workloads, such as graphics processing workloads, and in a specific example, ray tracing workloads. The workloads include a scheduling key, which is one basis on which the groupings can be formed. Workloads grouped together can all execute from the same source of instructions, on one or more different private data elements. Such workloads can recursively instantiate other workloads that reference the same private data elements. In some examples, the scheduling key can be used to identify a data element to be used by all the workloads of a grouping. Memory conflicts to private data elements are handled through scheduling of non-conflicted workloads or specific instructions and/or deferring conflicted workloads instead of locking memory locations.

Abstract: Aspects comprise systems implementing 3-D graphics processing functionality in a multiprocessing system. Control flow structures are used in scheduling instances of computation in the multiprocessing system, where different points in the control flow structure serve as points where deferral of some instances of computation can be performed in favor of scheduling other instances of computation. In some examples, the control flow structure identifies particular tasks, such as intersection testing of a particular portion of an acceleration structure, and a particular element of shading code. In some examples, the aspects are used in 3-D graphics processing systems that can perform ray tracing based rendering.

Abstract: Graphics processing systems and methods provide soft shadowing effects into rendered images. This is achieved in a simple manner which can be implemented in real-time without incurring high processing costs so it is suitable for implementation in low-cost devices. Rays are cast from positions on visible surfaces corresponding to pixel positions towards the center of a light, and occlusions of the rays are determined. The results of these determinations are used to apply soft shadows to the rendered pixel values.

Abstract: Systems and methods of geometry processing, for rasterization and ray tracing processes provide for pre-processing of source geometry, such as by tessellating or other procedural modification of source geometry, to produce final geometry on which a rendering will be based. An acceleration structure (or portion thereof) for use during ray tracing is defined based on the final geometry. Only coarse-grained elements of the acceleration structure may be produced or retained, and a fine-grained structure within a particular coarse-grained element may be Produced in response to a collection of rays being ready for traversal within the coarse grained element. Final geometry can be recreated in response to demand from a rasterization engine, and from ray intersection units that require such geometry for intersection testing with primitives. Geometry at different resolutions can be generated to respond to demands from different rendering components.

Abstract: Rendering systems that can use combinations of rasterization rendering processes and ray tracing rendering processes are disclosed. In some implementations, these systems perform a rasterization pass to identify visible surfaces of pixels in an image. Some implementations may begin shading processes for visible surfaces, before the geometry is entirely processed, in which rays are emitted. Rays can be culled at various points during processing, based on determining whether the surface from which the ray was emitted is still visible. Rendering systems may implement rendering effects as disclosed.

Abstract: Ray tracing systems have computation units (“RACs”) adapted to perform ray tracing operations (e.g. intersection testing). There are multiple RACs. A centralized packet unit controls the allocation and testing of rays by the RACs. This allows RACs to be implemented without Content Addressable Memories (CAMs) which are expensive to implement, but the functionality of CAMs can still be achieved by implemented them in the centralized controller.

Abstract: Graphics processing system configured to perform ray tracing. Rays are bundled together and processed together. When differential data is needed by a shader, the data of a true ray in the bundle can be used rather than processing separate tracker rays.

Abstract: Rendering systems that can use combinations of rasterization rendering processes and ray tracing rendering processes are disclosed. In some implementations, these systems perform a rasterization pass to identify visible surfaces of pixels in an image. Some implementations may begin shading processes for visible surfaces, before the geometry is entirely processed, in which rays are emitted. Rays can be culled at various points during processing, based on determining whether the surface from which the ray was emitted is still visible. Rendering systems may implement rendering effects as disclosed.

Abstract: Ray tracing units, processing modules and methods are described for generating one or more reduced acceleration structures to be used for intersection testing in a ray tracing system for processing a 3D scene. Nodes of the reduced acceleration structure(s) are determined, wherein a reduced acceleration structure represents a subset of the 3D scene. The reduced acceleration structure(s) are stored for use in intersection testing. Since the reduced acceleration structures represent a subset of the scene (rather than the whole scene) the memory usage for storing the acceleration structure is reduced, and the latency in the traversal of the acceleration structure is reduced.

Abstract: Graphics processing systems can include lighting effects when rendering images. “Light probes” are directional representations of lighting at particular probe positions in the space of a scene which is being rendered. Light probes can be determined iteratively, which can allow them to be determined dynamically, in real-time over a sequence of frames. Once the light probes have been determined for a frame then the lighting at a pixel can be determined based on the lighting at the nearby light probe positions. Pixels can then be shaded based on the lighting determined for the pixel positions.

Abstract: Ray tracing, and more generally, graphics operations taking place in a 3-D scene, involve a plurality of constituent graphics operations. Responsibility for executing these operations can be distributed among different sets of computation units. The sets of computation units each can execute a set of instructions on a parallelized set of input data elements and produce results. These results can be that the data elements can be categorized into different subsets, where each subset requires different processing as a next step. The data elements of these different subsets can be coalesced so that they are contiguous in a results set. The results set can be used to schedule additional computation, and if there are empty locations of a scheduling vector (after accounting for the members of a given subset), then those empty locations can be filled with other data elements that require the same further processing as that subset.

Abstract: In some aspects, systems and methods provide for forming groupings of a plurality of independently-specified computation workloads, such as graphics processing workloads, and in a specific example, ray tracing workloads. The workloads include a scheduling key, which is one basis on which the groupings can be formed. Workloads grouped together can all execute from the same source of instructions, on one or more different private data elements. Such workloads can recursively instantiate other workloads that reference the same private data elements. In some examples, the scheduling key can be used to identify a data element to be used by all the workloads of a grouping. Memory conflicts to private data elements are handled through scheduling of non-conflicted workloads or specific instructions and/or deferring conflicted workloads instead of locking memory locations.

Abstract: Graphics processing systems and methods provide soft shadowing effects into rendered images. This is achieved in a simple manner which can be implemented in real-time without incurring high processing costs so it is suitable for implementation in low-cost devices. Rays are cast from positions on visible surfaces corresponding to pixel positions towards the center of a light, and occlusions of the rays are determined. The results of these determinations are used to apply soft shadows to the rendered pixel values.

Abstract: Rendering systems that can use combinations of rasterization rendering processes and ray tracing rendering processes are disclosed. In some implementations, these systems perform a rasterization pass to identify visible surfaces of pixels in an image. Some implementations may begin shading processes for visible surfaces, before the geometry is entirely processed, in which rays are emitted. Rays can be culled at various points during processing, based on determining whether the surface from which the ray was emitted is still visible. Rendering systems may implement rendering effects as disclosed.

Abstract: Systems and methods of geometry processing, for rasterization and ray tracing processes provide for pre-processing of source geometry, such as by tessellating or other procedural modification of source geometry, to produce final geometry on which a rendering will be based. An acceleration structure (or portion thereof) for use during ray tracing is defined based on the final geometry. Only coarse-grained elements of the acceleration structure may be produced or retained, and a fine-grained structure within a particular coarse-grained element may be Produced in response to a collection of rays being ready for traversal within the coarse grained element. Final geometry can be recreated in response to demand from a rasterization engine, and from ray intersection units that require such geometry for intersection testing with primitives. Geometry at different resolutions can be generated to respond to demands from different rendering components.

Abstract: Aspects comprise systems implementing 3-D graphics processing functionality in a multiprocessing system. Control flow structures are used in scheduling instances of computation in the multiprocessing system, where different points in the control flow structure serve as points where deferral of some instances of computation can be performed in favor of scheduling other instances of computation. In some examples, the control flow structure identifies particular tasks, such as intersection testing of a particular portion of an acceleration structure, and a particular element of shading code. In some examples, the aspects are used in 3-D graphics processing systems that can perform ray tracing based rendering.

Abstract: Rendering systems that can use combinations of rasterization rendering processes and ray tracing rendering processes are disclosed. In some implementations, these systems perform a rasterization pass to identify visible surfaces of pixels in an image. Some implementations may begin shading processes for visible surfaces, before the geometry is entirely processed, in which rays are emitted. Rays can be culled at various points during processing, based on determining whether the surface from which the ray was emitted is still visible. Rendering systems may implement rendering effects as disclosed.