• Focus on discussing 3D core technology and features of PowerVR Series2 hardware.
• 3D core used in a number of parts including PC, console and arcade
• PC 2D/3D product available Summer 98 with development systems available E3
• First development units delivered in Feb 98

Topics to be covered 

• The Architecture
• 
  Differences between first and second generation platform described. As well as a discussion about where the architecture is heading. 
• Performance
• 
  Where focus was placed 
• Image Quality
• 
  What enhancements were made 
• Development

Architecture 101 

Same fundamentals as first generation 

• Tile based: Screen broken down into 32x16 tiles
• (PCX2 internally rendered at 32x1)
• Deferred Texturing: Only display visible pixels.
• On chip HSR: Faster method of Z -buffering
• Low Memory Bandwidth: Due to features above.
• Low cost: Single chip (~$30), Inexpensive memory
• Asynchoronous Rendering: Host CPU free during render

New Enhancements 

• Full 32bit floating point geometry and texture setup engine 
• Hardware tiling engine 
• 2 On chip accumulation buffers 
• Unified memory architecture (2D & 3D part) 
• PCI or AGP 2x with side band 
• 1600 x 1200 Resolution (Super sampling up to 2048x2048) 
• Increased Z compare modes (ignore, <, =, <=, >, !=, >=, always) 

Performance 102 - The Numbers 

• Sustained 1.2 million front facing, lit, textured, shaded, Z sorted polygons per second on a Intel P2-333. 
• Actual screen fill rate of 100mpps(1clk/pixel). 
• Using conventional fill rate methodology this translates to PowerVR SG having a much higher fill rate. At 1.5x overdraw this translates to a conventional fill rate of 150mpps. 
• Or another way to put it: 
• 1024x768 @ 60 fps with 'n' overdraw & 25% translucency=~59mpps (room to spare!) 

Performance 102 - Silicon Enhancements 

• Hardware Tiling Engine - Tiles no longer clipped within software. 
• Increased Processing Elements - Tiles are now rendered at 32x16 pixels instead of 32x1 as on PCX2. 
• Per-pixel hardware translucency sorting - No longer expects translucent polygons to be pre-sorted in software. 
• Increased clock rate and shrunk die size - Now 100 MHz at 0.25 microns. 

Performance 102 - Maximizing Performance 

• Strips/Fans - Both reduce amount of vertex data. Strips directly supported in hardware. Fans done by using Strips internally. A Strip is a polygon that shares two of it's vetices with another polygon. A Fan is a polygon that shares one of it's vertices with another polygon. 
• Compressed Textures -  Large textures should be compressed to reduce the amount of bus and memory transfer time. 
• Overlap - Asynchronous rendering, freeing up host CPU to continue with your game code. 
• Enable Super Sampling & Higher filtering modes - Affects performance but can improve image quality significantly! 

Image Quality - Features 

• Additional Fog Support - per pixel, Vertex Fog, and/or Fixed/Loadable Table 
• Perspective correct RGBA Gouraud Shading as well as intensity 
• Specular Highlights with Offset Color 
• Advanced Image Filtering Modes (per polygon) - Point Sample Bilinear (1 cycle), Trilinear (2 cycles), Anisotropic (4 cycles). 
• 32-bit Floating Point Z-buffer Accuracy - Reduce shimmering, tears and artifacts. 
• Full Multi-Texture and Multi-Pass Rendering 
• Texture sizes up to 1024x1024 

Image Quality - Texture formats & Blended Modes 

Texture Formats 

• 8-bit Palletized (including 8888 palettes) 
• 555 RGB, 565 RGB 
• 5551 RGBA, 4444 RGBA 
• 422 YUV 
• VQ Compression (up to an 8:1 compression ratio) 
• Bump maps 

Blending Modes  
OpenGL and D3D blending modes are supported  
All blending done internally at 32 bits of color to reduce artifacts 

Image Quality - Bump Mapping 

• Full hardware bump mapping support 
• Bump maps are supplied using a Height Map 
• Bump map is internally converted to an intermediate light map 
• Since you have the light map you then may specify how it should be blended with the original texture 
• Accessible in SGL Direct (native api) as well as DirectX 6 

Image Quality - Vector Quatization 

• Texture Compression delivering up to an 8:1 lossy image 
• Front end compression required (typically 3 sec/texture) 
• Code book is a variable size up to 256x4 entries (RGBA @ 16bits each) 
• Decompression quick and basically for free 
• Able to use with a mix of compressed and non compressed textures 

Image Quality - Full Scene Super Sampling 

• Image is rendered to a specified resolution and then is scaled to the users view port using a bi-cubic filter (similar to Photo Shop). 
• You may specify any X and/or Y screen size up to 2048x2048 - the maximum screen output resolution for PowerVR is 1600x1200. 
• Benefit is very easy to use - no need to track edges and specify which are aliased. Simply turn it on and specify the resolution. 
• Only penalty for performance is fill rate - however it is not equivalent to the full proportional to the extra pixels. 

Image Quality - Generalized Modifier Volumes 

• Extension to what was known on PowerVR first generation as light and shadow volumes 
• Sample images from a demo available in our SDK which shows how one may use modifier volumes 
• A second set of parameter data is supplied per modifiable ploygon/model. When the object is in/out of the specified volume, the second set of parameters may then be used. 
• Examples of usage - X-Ray guns, ships whose cloaks start to fail as they pass through the tail of a comet 

Development 

• Full support for DirectX 5/6 (some features only accessible under 6 - such as multi-texturing, bump mapping), OpenGL certified ICD, and SGL Direct (native API) 
• Very thin API - much of the previous work done in the drivers with the PCX2 has now been brought down into the silicon 
• World wide developer support with local staff in Silicon Valley, Austin, London, Australia and Japan 
• Development kits available to all qualified developers this summer. Either contact me or go to our web site at http://www.powervr.com 

Development - WWW site 

• This web site is currently only available to qualified developers under NDA 
• Look forward to announcements soon regarding publicly available developers materials 
• Documentation & Reference Manuals 
• Programming Guides, Optimization Docs 
• Technology Information & News 
• Lastest Drivers, Debug & Timing Utilities 
• General Tools & Utilities 
• FAQ Section 
• Tips & Tricks Section 
• Example Programs 
• Special Events, e.g. Competitions