David Luebke 1 9/4/2015 Real-Time Rendering & Game Technology CS 446/651 David Luebke

David Luebke 2 9/4/2015 Demo Time ● We will open classes with 5 minute ‘demo time’ ■ Students pick something (e.g., a game) to demo ○ Main focus should be real-time graphics, not game play ○ In-engine cut scenes, graphics-related game play okay ■ Students responsible for setting up demo platform! ○ Need to get here 10 minutes early to work with A/V guy ○ I can provide PC (NV, ATI) with warning ■ Demo duty rotates each class ○ Send around a sign-up sheet

David Luebke 3 9/4/2015 Comparison: SGI InfiniteReality (1998) vs. NVIDIA GeForce4 (2002) MetricSGI IRNVIDIA NV25 Triangles/demosec13 million75 million Pixels/demosec1.2 billion Texture memory64 MB128 MB Bump mappingNopeNo sweat Programmable vertex engine?You kidding?Yup Programmable pixel engine?Get realYup Form factorMini-fridgevideocassette Cost$100,000$400 The real news!!!

David Luebke 4 9/4/2015 Comparison: SGI InfiniteReality (1998) vs. NVIDIA GeForce 7800 GTX (2005) MetricSGI IRNVIDIA G70 Triangles/demosec13 million860 million Pixels/demosec6.9 billion Texture memory64 MB128 MB Bump mappingNope Trivial Programmable vertex engine?You kidding?Yup Programmable pixel engine?Get realYup Form factorMini-fridgevideocassette Cost$100,000$500 The real news!!!

David Luebke 5 9/4/2015

David Luebke 6 9/4/2015 GPU history ProductProcessTransMHz Fill Rate MF/sec Geom Rate Mtri/sec GFLOPS (MUL) May-99GeForce M Dec-99GeForce 2 GTS0.1825M Sep-00GeForce M Sep-01GeForce 4 Ti0.1563M Aug-02 GeForce FX M Jan-03 GeForce FX M Dec-03GeForce M Tables & data courtesy Ian Buck, Stanford, and Nick Triantos, NVIDIA NVIDIA historicals

David Luebke 7 9/4/2015 GPU history ProductProcessTransMHz GFLOPS (MUL) Aug-02 GeForce FX M5008 Jan-03 GeForce FX M47520 Dec-03GeForce M40053 NVIDIA historicals translating transistors into performance ■ 1.8x increase of transistors ■ 20% decrease in clock rate ■ 6.6x GFLOP speedup

David Luebke 8 9/4/2015 Graphics Performance: GPU vs CPU Growth Trends Graph courtesy John Owens Data courtesy Nick Triantos, NVIDIA

David Luebke 9 9/4/2015 Summary ● These are interesting times for real-time rendering: ■ Commodity graphics cards are fantastically capable ■ The rate of ongoing improvement is dizzying ○ Raw performance ○ Feature set ■ New algorithms, long-offline algorithms becoming possible ■ Hard to keep up, even for “experts” ● What’s pushing the technology curve?

David Luebke 10 9/4/2015 Video Games ● Undoubtedly the driving force behind this revolution ■ In 2002 the video game industry surpassed the film industry (sort of) ■ Commodity parts: Workstations vs PCs vs consoles (vs cell phones?)

David Luebke 11 9/4/2015 The Course: General Topics ● This class will study real-time rendering, with a particular focus on the hardware and algorithms underlying 3D game engines ■ Generally PC hardware rather than consoles ■ Bit more emphasis on NVIDIA hardware ■ Generally OpenGL (DX more apropos, but…) ● We won’t study much or any: ■ Gameplay, storylines, AI, game art, production process, artist tools, network layers, OO game design, audio, physics, animation

David Luebke 12 9/4/2015 The Course: Workload ● This is a project course, all grades from programming assignments: ■ One or two completely individual assignments ○ Game design, “Building blocks” of a game engine ■ Big team project: a 3D video game/graphical experience ■ Individual assignments in context of team project ○ Add features to your team’s game engine ● Think graduate-level course ■ A game engine is a big program ■ Will likely be more work (but also more rewarding) than any course you’ve ever had

David Luebke 13 9/4/2015 The Course: Syllabus ● The web page is the syllabus…

David Luebke 14 9/4/2015 Review: The Graphics Pipeline ● The next lecture will go over the traditional graphics pipeline ● The big picture: ApplicationGeometryRasterizer

David Luebke 15 9/4/2015 Programmable Pipelines ● Recent hardware offers the option of replacing portions of the pipeline with user-programmed stages ■ Vertex shader: replaces fixed-function transform and lighting ■ Pixel shader: replaces texturing stages

David Luebke 16 9/4/2015 Programmable Pipelines ● The amount of programmability is increasing by leaps and bounds ■ Vertex shaders: more instructions, variable indexing, fully MIMD branching, subroutines ■ Pixel shaders: still SIMD, but with more instructions, unlimited texture accesses, pixel kill ■ Coming soon: unified shaders, memory scatter ● The data precision is also improving ■ IEEE floating point throughout the pipeline! ■ Various versions

David Luebke 17 9/4/2015 To think about: ● What are some possible bottlenecks in system performance of a graphics/game engine? ● Does it make any difference to sort your geometry front-to- back or back-to-front when using a depth-buffer? ● Will your textured polygons render faster if MIP-mapping is enabled or disabled? ● Does the order that you traverse polygons (i.e., issue vertices using glVertex() or something like it) matter?