GPU Displacement Ray Tracing with RMIP Bounds and Prism Intersection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional scene rendering systems face inefficiencies in rendering textured objects due to the need for high-resolution geometry maintenance, large memory footprints, and limited execution performance, especially when dealing with complex displacement maps and dynamic texture displacement content.
Innovation Solution
The use of a rectangular minmax image pyramid (RMIP) data structure to provide displacement bounds for arbitrary axis-aligned rectangular regions in 2D texture space, combined with an iterative bound reduction process during ray tracing, allows for precise and efficient determination of ray intersections.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional scene rendering systems maintain high-resolution geometry for textured objects, then rendering accuracy is improved, but memory footprint increases and execution performance deteriorates
Solution Approach 1:
The patent segments the displacement map into a hierarchical pyramid structure (RMIP) where the displacement bounds are divided into multiple levels of resolution. Coarse levels provide broad bounds while fine levels provide precise bounds, allowing the system to query only the necessary resolution level for each ray intersection test, thus avoiding the need to maintain and process full high-resolution geometry everywhere.
Solution Approach 2:
The patent pre-computes the displacement bounds pyramid structure from the displacement map before rendering. This preliminary action creates a compressed hierarchical representation that can be quickly queried during ray tracing without requiring real-time computation of high-resolution geometry, improving execution performance while preserving rendering accuracy when needed.
2Measurement precision
If conventional scene rendering systems use detailed geometry for complex displacement maps, then rendering quality is improved, but memory footprint increases
Solution Approach 1:
The displacement bounds are segmented into a multi-level pyramid structure where each level stores bounds at a different resolution. This segmentation allows the system to represent complex displacement maps using progressively coarser approximations at different levels, dramatically reducing memory requirements compared to storing full high-resolution geometry while preserving the ability to query precise bounds when needed.
Solution Approach 2:
The patent creates a compressed hierarchical copy (the RMIP structure) of the displacement information that captures the essential bounds data at multiple resolutions. This copy serves as a surrogate for the full displacement map during ray tracing, reducing memory footprint while maintaining the ability to achieve high rendering quality by querying appropriate resolution levels.
3Measurement precision
If conventional ray tracing processes traverse all geometry for each ray, then intersection accuracy is improved, but traversal time increases
Solution Approach 1:
The displacement bounds pyramid is pre-computed and organized into a hierarchical structure that enables efficient ray traversal. During rendering, rays traverse this pre-organized structure from coarse to fine levels, allowing the system to quickly eliminate regions that cannot contain intersections and only detailed examination of regions that might contain intersections, significantly reducing traversal time while maintaining intersection accuracy.
Solution Approach 2:
The patent implements a dynamic traversal strategy where the level of detail examined adapts based on the ray's position and direction. The hierarchical RMIP structure allows the renderer to dynamically adjust the resolution of bounds checking at different stages of ray traversal, using coarse bounds for early culling and fine bounds only where necessary, optimizing the balance between traversal time and intersection accuracy.
Data Source
AI summary
A system generates, based on a displacement bounds data structure and a triangle mesh modeling a surface of a 3D virtual object within a 3D virtual scene, a displaced triangle mesh including one or more displaced surface bounding prisms, each of the one or more displaced surface bounding prisms displaced from a respective base triangle of a plurality of base triangles of the triangle mesh structure based on displacement bounds defined in a displacement bounds data structure for an area of a 2D texture space corresponding to a location of the respective base triangle defined by the 3D virtual scene. The system performs, using the displaced triangle mesh structure, a ray tracing process for a ray associated with a pixel of a 2D image of the virtual scene including determining, responsive to determining the ray intersects the particular displaced surface bounding prism, a location of an intersection of the ray.