RADEON

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RADEON 9700Architecture and 3D Performance

• Gordon Elder

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RADEON 9700

• What is the RADEON 9700 ?
• Programmability(SMARTSHADER 2.0)
• First Full Floating Point Graphics Pipeline
• Enables Compilation of High Level Shading
  Languages
• Performance
• High Bandwidth
• Parallelism
• Efficiency
• Image Quality (SMOOTHVISION 2.0)
• Multisample Antialiasing
• Anisotropic Texture Filtering

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Image Generation with Image Mapping 1st
Generation Programmability

• Idea Texture Mapping, Blinn and Newell 1976
• Implementation SGI VGXT 1990
• Hardwired Vertex Processing
• Hardwired Fragment Processing with a Single
  Texture
• Result Environment Mapping and other effects

Blinn, J. F. and Newell, M. E. Texture and
reflection in computer generated images.
Communications of the ACM Vol. 19, No. 10
(October 1976), 542-547
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Image Generation with Texture Composition2nd
Generation Programmability

• Idea Shade trees, R. Cook 1984
• Implementation RADEON 8500 2001
• Limited Vertex Programmability
• Limited Fragment Processing
• Multiple Textures
• Fixed Point Data
• Short Programs
• Result Current generation of effects.

Robert L. Cook Shade Trees. Computer Graphics
Vol. 18, No. 3, (July 1984), 223-231
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Image Generation with General Purpose Floating
Point Math Texturing 3rd Generation
Programmability

• Idea RenderMan, Pixar 1987
• Implementation ATI RADEON 9700 2002
• Advanced Vertex Programmability
• Advanced Fragment Programmability
• Floating Point Data
• Rich Instruction Set
• Large Instruction Store
• Result Enabling Cinematic Rendering
• Compiling RenderMan, Maya, etc.

Willina T. Reeves, David H. Salesin, Robert L.
Cook Rendering Antialiased Shadows with Depth
Maps. Computer Graphics Vol. 21, No. 4, (July
1987), 283-291
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SMARTSHADER 2.0

• Next-generation programmable shader technology
• Enabling cinema-quality effects in real time
• First complete DirectX 9.0 feature support
• 2.0 Vertex and Pixel Shaders
• Floating Point Pixel Pipelines
• 128-bit Floating Point Texture and Frame Buffer
  Formats
• Two-Sided Stencil Shadow Acceleration
• High Precision 32-bpp (1010102) Display Mode
• Higher Order Surface Enhancements
• Full feature set also available for OpenGL
• OpenGL Shading Language Support

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Vertex Shaders (SMARTSHADER 2.0)

• Flow Control
• Loops, jumps and subroutines
• Allow re-use of certain parts of theshader code
• Avoids repetition and saves instructions
• More Instructions, More Complex Effects
• Up to 65,280 instructions per pass
• Vertex shaders can be much more complex than they
  were in DX8

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Pixel Shaders (SMARTSHADER 2.0)

• More Complex Shaders by an Order of Magnitude
• Up to 160 instructions per pass
• 32 address ops, 64 color ops, 64 alpha ops
• Compared with 12 instructions total in DX8.0
• Multi-pass rendering support
• High precision 128-bit floating point data
  formats for storing intermediate results between
  passes
• Shaders can now effectively be thousands of
  instructions long performance is the only
  limitation
• 24-bit per component floating point precision for
  all pixel shader operations - necessary for
  cinema-quality effects
• Allows shaders written in any present or future
  language to run on hardware with SMARTSHADER 2.0
• Even high level languages like RenderMan can now
  be compiled to run on RADEON 9700 in real time
• Pixel shader can also implement complex Image
  Processing algorithms

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RADEON 9700 Performance

• Key design elements for best performance High
  Bandwidth, Parallelism, Efficiency
• High Bandwidth
• AGP 8x provides 2 GB/sec transfers to or from the
  CPU or system memory.
• 310 MHz 256-bit DDR Memory Interface provides
  20 GB/sec access to the Frame Buffer
• Internal 256-bit data busses for Color, Texture
  and Z
• Parallelism
• 4 Vertex Engines running at 325MHz provides
  325 Mtriangles/sec (4 clocks per vertex per
  engine)
• 8 Pixels/Clock Rasterization Architecture running
  at 325MHz provides a peak fill rate of 2.6
  Gpix/sec

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RADEON 9700 Performance (cont.)

• Efficiency
• Graphics systems tend to be Memory Bandwidth
  limited. The RADEON 9700 is no exception. So it
  is important to use the bandwidth efficiently.
• Hierarchical and Early Z checking allows pixels
  to be rejected before the pixel shader. This is
  very important when shader programs are long.
• Color, Texture and Z caches reduce memory
  bandwidth utilization. Benefit from spacial and
  temporal locality.
• Lossless Color and Z data compression reduce
  memory bandwidth utilization.
• Compressed Textures can be utilized to reduce
  memory bandwidth utilization.
• Fast Color and Z clears eliminate need to access
  memory for clears
• HyperZ III

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RADEON 9700 Performance (cont.)

• One more interesting thing..
• Scalability
• The RADEON 9700 Architecture is capable of
  scaling up to 256 simultaneous units

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Image Quality (SMOOTHVISION 2.0 )

• Performance matters too
• Pixel antialiasing and anisotropic texture
  filtering improve image quality only if they are
  enabled.
• Just going to higher resolutions isnt the answer
  for improved image quality.
• Artifacts due to poor texture sampling remain.
• Dynamic antialiasing artifacts are still very
  visible.
• Sufficient performance for high resolution
  display, high quality texture filtering, and
  antialiasing is needed.
• The RADEON 9700 was architected to do all three
  simultaneously.

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Anti-Aliasing (SMOOTHVISION 2.0)

• Non-Grid Programmable Multi-Sampling
• 2, 4, or 6 samples per pixel
• Sample positions provide the maximum quality per
  sample
• Lossless Z and Color compression minimizes
  bandwidth cost of higher sample counts.
• Per Sample Gamma Correction
• Takes gamma into account when blending samples
• Creates smoother edge transitions

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Anisotropic Filtering (SMOOTHVISION 2.0)

• Improved Adaptive Algorithm
• Up to 16 Trilinear Samples (128-tap)
• Calculates optimal number of samples foreach
  polygon
• Delivers full image quality benefit while
  conserving memory bandwidth

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RADEON 9700 Demos

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Conclusion