公开(公告)号：US20240095996A1

公开(公告)日：2024-03-21

申请号：US17946509

申请日：2022-09-16

Applicant: NVIDIA Corporation

Inventor： Gregory MUTHLER ,  John BURGESS ,  Eric ENDERTON ,  Nikhil DIXIT ,  Josh NOEL

IPC: G06T15/06

CPC classification number: G06T15/06

Abstract: To improve the efficiency of bounding volumes in a hardware based ray tracer, we employ a sheared axis-aligned bounding box to approximate an oriented bounding box typically defined by rotations. To achieve this, the bounding volume hierarchy builder shears an axis-aligned box to fit tightly around its enclosed oriented geometry in top level or bottom level space, then computes the inverse shear transform. The bounds are still stored as axis-aligned boxes in memory, now defined in the new sheared coordinate system, along with the derived parameters to transform a ray into the sheared coordinate system before testing intersection with the boxes. The ray-bounding volume intersection test is performed as usual, just in the new sheared coordinate system. Additional efficiencies are gained by constraining the number of shear dimensions, constraining the shear transform coefficients to a quantized list, sharing a shear transform across a collection of bounds, performing a shear transform only for ray-bounds testing and not for ray-geometry intersection testing, and adding a specialized shear transform calculator/accelerator to the hardware.

公开(公告)号：US20230078932A1

公开(公告)日：2023-03-16

申请号：US17946828

申请日：2022-09-16

Applicant: NVIDIA Corporation

Inventor： John BURGESS ,  Gregory MUTHLER ,  Nikhil DIXIT ,  Henry MORETON ,  Yury URALSKY ,  Magnus ANDERSSON ,  Marco SALVI ,  Christoph KUBISCH

IPC: G06T15/06 ,  G06T17/20 ,  G06T15/40 ,  G06T19/20

Abstract: A Displaced Micro-mesh (DMM) primitive enables high complexity geometry for ray and path tracing while minimizing the associated builder costs and preserving high efficiency. A structured, hierarchical representation implicitly encodes vertex positions of a triangle micro-mesh based on a barycentric grid, and enables microvertex displacements to be encoded efficiently (e.g., as scalars linearly interpolated between minimum and maximum triangle surfaces). The resulting displaced micro-mesh primitive provides a highly compressed representation of a potentially vast number of displaced microtriangles that can be stored in a small amount of space. Improvements in ray tracing hardware permit automatic processing of such primitive for ray-geometry intersection testing by ray tracing circuits without requiring intermediate reporting to a shader.

公开(公告)号：US20230081791A1

公开(公告)日：2023-03-16

申请号：US17946515

申请日：2022-09-16

Applicant: NVIDIA Corporation

Inventor： John BURGESS ,  Gregory MUTHLER ,  Nikhil DIXIT ,  Henry MORETON ,  Yury URALSKY ,  Magnus ANDERSSON ,  Marco SALVI ,  Christoph KUBISCH

IPC: G06T17/20 ,  G06T17/10 ,  G06T15/06 ,  G06T15/40

Abstract: A Displaced Micro-mesh (DMM) primitive enables high complexity geometry for ray and path tracing while minimizing the associated builder costs and preserving high efficiency. A structured, hierarchical representation implicitly encodes vertex positions of a triangle micro-mesh based on a barycentric grid, and enables microvertex displacements to be encoded efficiently (e.g., as scalars linearly interpolated between minimum and maximum triangle surfaces). The resulting displaced micro-mesh primitive provides a highly compressed representation of a potentially vast number of displaced microtriangles that can be stored in a small amount of space. Improvements in ray tracing hardware permit automatic processing of such primitive for ray-geometry intersection testing by ray tracing circuits without requiring intermediate reporting to a shader.