, Russian Federation
, Russian Federation
, Russian Federation
GRNTI 50.07 Теоретические основы вычислительной техники
BBK 3297 Вычислительная техника
Hardware acceleration of ray tracing is an active research field, but only with the release of Nvidia Turing architecture GPUs it became widely available. Nvidia RTX is a proprietary hardware ray tracing acceleration technology available in Vulkan and DirectX APIs as well as through Nvidia OptiX. Since the implementation details are unknown to the public, there are a lot of questions about what it actually does under the hood. To find answers to these questions, we implemented classic path tracing algorithm using RTX via both DirectX and Vulkan and conducted several experiments with it to investigate the inner workings of this technology. We tested actual hardware implementation of RTX technology on RTX2070 GPU and the software fallback in the driver on GTX1070 GPU. In this paper we present results of these experiments and speculate on the internal architecture of RTX.
photo-realistic rendering, ray tracing, hardware acceleration, GPU
1. Aila T., Karras T. Architecture considerations for tracingincoherent rays //High-performance Graphics.– Eurographics Association, 2010. – p. 113-122.
2. Deng Y. et al. Toward real-time ray tracing: A survey onhardware acceleration and microarchitecture tech-niques //ACM Computing Surveys (CSUR). – 2017. – . 50. – №. 4.– p. 58.
3. Gribble C. P., Ramani K. Coherent ray tracing viastream filtering //2008 IEEE Symposium on Interac-tiveRay Tracing. – IEEE, 2008. – p. 59-66.
4. Hall. D. The AR350: Today’s ray trace renderingprocessor. //Eurographics/SIGGRAPH workshop onGraphics hardware - Hot 3D Session 1, 2001
5. Kajiya J. T. The rendering equation //ACM SIG-GRAPHcomputer graphics. – ACM, 1986. – . 20. –№. 4. – p.143-150.
6. Keely S. Reduced precision hardware for ray tracing.//Proc.HPG. – 2014. – p. 29-40.
7. Kopta D. et al. An energy and bandwidth efficient raytracing architecture //High-performance Graphics. –ACM,2013. – p. 121-128.
8. Lee W. J. et al. SGRT: A mobile GPU architecture forreal-time ray tracing //High-performance graphicsconference. – ACM, 2013. – p. 109-119.
9. Meißner M. et al. VIZARD II: a reconfigurable interactive volume rendering system //ACM Eurographics conf.on Graphics hardware. – Eurographics Associa-tion,2002. – p. 137-146.
10. Nah J. H. et al. T&I engine: traversal and intersectionengine for hardware accelerated ray tracing //ACMTransactions on Graphics (TOG). – ACM, 2011. – .30. – №. 6. – p. 160.
11. Nah J. H. et al. RayCore: A ray-tracing hardware architecture for mobile devices //ACM Transactions onGraphics (TOG). – ACM, 2014. – . 33. – №. 5. – p. 162.
12. Pfister H. et al. The VolumePro real-time ray-castingsystem. //Computer graphics and interactive techniques. – N.Y.: Association for Computing Machinery.– 1999. – p. 251-260.
13. Schmittler J., Wald I., Slusallek P. SaarCOR: a hardware architecture for ray tracing //ACM SIGGRAPH conf.on Graphics hardware. – Eurographics Associa-tion,2002. – p. 27-36.
14. Schmittler J. et al. Realtime ray tracing of dynamic scenes on an FPGA chip //ACM SIGGRAPH/EUROGRAPHICS conf. on Graphics hard-ware.– ACM, 2004. – p. 95-106.
15. Shkurko K. et al. Dual streaming for hardwareaccelerated ray tracing //High Performance Graphics.– ACM, 2017. – p. 12.
16. Spjut J. et al. TRaX: A multi-threaded architecturefor real-time ray tracing //Symposium on ApplicationSpecific Processors. – IEEE, 2008. – p. 108-114.
17. Stich M. Real-time raytracing with Nvidia RTX,GTC EU 2018
18. Wald I. et al. RTX Beyond Ray Tracing: Exploringthe Use of Hardware Ray Tracing Cores for Tet-MeshPoint Location. Authors’ Preprint — to be presented atHigh-Performance Graphics 2019
19. Whitted T. An improved illumination model for shadeddisplay //ACM SIGGRAPH – ACM, 1979. – . 13. – №. 2.– . 14.
20. Woop S., Schmittler J., Slusallek P. RPU: a programmable ray processing unit for realtime ray trac-ing //ACM Transactions on Graphics (TOG). – ACM,2005. – . 24. – №. 3. – p. 434-444.
21. Imagination technologies. PowerVR Ray Tracing.2019. URL = https://www.imgtec.com/graphicsprocessors/architecture/powervr-ray-tracing/
22. Nvidia Turing architecture whitepaper. 2019URL = https://www.nvidia.com/content/dam/en-zz/Solutions/design-visualization/technologies/turingarchitecture/NVIDIA-Turing-Architecture-Whitepaper.pdf
23. Nvidia RTX Ray tracing developer resources. 2019URL = https://developer.nvidia.com/rtx/raytracing RayTracing Systems, Keldysh Institute of ApplyedMathematics, Moscow State Uiversity.
24. Hydra Renderer. Open source rendering system. 2019 URL =https://github.com/Ray-Tracing-Systems/
25. HydraAPI Vulkanspecification. 2019 URL = https://www.khronos.org/registry/vulkan/specs/1.1-extensions/html/vkspec.html
