Dr A Sahu
Dept of Comp Sc & Engg.
IIT Guwahati
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• Intel 945 Motherboard architecture
–GMCH
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NVIDIA GPU Architecture
ATI Readon Architecture
DirectX, OpenGL, OpenCL
Advance GPU from ATI and AMD
–Introduction to Nvidia Cuda
Programming
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• From 20 Oct 2010 to 26 Oct 2010 Class will
be at allocated Room 1201
• There will be multimedia workshop in this
Seminar room 20-26 Nov 2010
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• Graphics and Memory Controller Hub
• Graphics Interface (GI) and PCI Express for
Graphics card support
• Host Interface (HI)
– Connect to processor and support HT, IntrDelivery,
12 in-order queue, etc.
• System Memory Interface (SMI)
– Connected to two channel DDR2
• Direct Media Interface (DMI)
– Connect to ICH7
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Intel
Pentium D Processor
Support for
Media Ext Card
Intel GMA 950
Graphics
DDR2
82945
GMCH/MCH
North Bridge
DDR2
PCI Express*
x16 Graphics
• Peripherals : HD monitor
• Interfaces : Intermediate Hardware
– Nvidia GPU card
• Interfaces : Intermediate Software/Program
– Nvidia GPU driver
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Char display (80x25 char, 5x7pixel=400x175)
CRT Monitor (400x600, 640x480,600x800)
LCD Monitor (1024x768,1280x1024,…)
Graphics visually more appealing
Display Line, Circle, Rectangle, Curve, Polygon
– Character using this primitives
– True type font
RED ARROW
Circle
6
Row
Ctr
0
Col
Ctr
CLK > 1024x768x50Hz
1 2 3 4 ….. …1023
0
1
2
1024x768 Pixel LCD
767
Frame Buffer
8x3=24 Bits
R B G
Refresh screen 50 time a Sec
7
24
longword
alpha
16
8
red
green
R
G
0
blue
Alpha represent premultiplied valued
0.5, 0, 1, 0
0, 0.5, 0
B
pixel
The intensity of each color-component within a pixel is an 8-bit value
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“truecolor” graphics-modes use 4-bytes per picture-element
VRAM
0
1
B
G
2
3
R
4
A
B
5
G
6
7
R
A
8
9
B
G
10
R
…
Video Screen
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• GPU : specialized processor that accelerates
3D or 2D graphics primitives operations
• Lots of Floating point operations
• Accelerates Primitives
– Line, circle, polygon, mesh, projection, sphere,
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3D application
3D API Commands
3D API:
OpenGL
DirectX/3D
CPU-GPU Boundary
GPU Command
& Data Stream
Vertex Index
Stream
GPU
Command
Assembled
polygon, line
& points
Primitive
Assembly
Pretransformed
Vertices
Programmable
Vertex
Processor
transformed
Vertices
Pixel
Updates
Pixel
Location
Stream
Rastereisation
Interpolation
Raster
Operation
Rastorized
Pretransformed
Fragments
Programmable
Fragment
Processors
Frame
Buffer
Transformed
Fragments
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Vertices
(x,y,z)
Memory
System
Vertex
Shadder
Vertex
Processing
Pixel
Shadder
Pixel
Processing
Texture
Memory
Pixel
R, G,B
Frame
Buffer
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The computing capacities of
graphics processing units (GPUs)
have improved exponentially in
the recent decade.
NVIDIA released a CUDA
programming model for GPUs.
The CUDA programming
environment applies the parallel
processing capabilities of the GPUs
to medical image processing
research.
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CUDA Cores 480 (Compute Unified Dev Arch)
Graphics Clock (MHz) 700
Processor Clock (MHz) 1401
Texture Fill Rate (billion/sec) 42
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Microsoft® DirectX® 11 Support
– DirectX 11 GPU with Shader Model 5.0 support designed for ultra high
performance in the new API’s key graphics feature
NVIDIA® 3D Vision™ Surround Ready
– Expand your games across three displays in full stereoscopic 3D for the
ultimate “inside the game” experience NVIDIA® Surround™ also supports
triple screen gaming with non-stereo displays.
Interactive Ray Tracing
– By tracing the path of light through a 3D scene, ray tracing to create
spectacular, photo-realistic visuals. Get a glimpse into the future of gaming
with ray tracing.
3-way NVIDIA SLI® Technology
– Industry leading 3-way NVIDIA SLI technology offers amazing performance
scaling by implementing 3-way AFR (Alternate Frame Rendering) for the
world’s premier gaming solution
• NVIDIA PhysX® Technology
– Enabling a totally new class of physical gaming interaction for a
more dynamic and realistic experience with GeForce.
• NVIDIA CUDA™ Technology
– CUDA technology accelerate the most demanding tasks such as
video transcoding, physics simulation, ray tracing
• 32x Anti-aliasing Technology
– Lightning fast, high-quality anti-aliasing at up to 32x sample
rates obliterates jagged edges.
• NVIDIA® PureVideo® HD Technology***
– The combination of hD video dec accn and post-processing that
delivers unprecedented picture clarity, smooth video, accurate
color, and precise image scaling for movies and video.
• PCI Express 2.0 Support. Dual-link DVI Support, HDMI 1.4
Elements of the graphics pipeline:
1. A scene description: vertices,
triangles, colors, lighting
2. Transformations that map the
scene to a camera viewpoint
3. “Effects”: texturing, shadow
mapping, lighting calculations
4. Rasterizing: converting geometry
into pixels
5. Pixel processing: depth tests,
stencil tests, and other per-pixel
operations.
1.
2.
3.
4.
Parameters controlling
design of the pipeline:
Where is the boundary
between CPU and GPU ?
What transfer method is
used ?
What resources are
provided at each step ?
What units can access
which GPU memory
elements ?
http://accelenation.com/?ac.id.123.2
Vertex
Transforms
CPU
• One of the first true 3D game cards
• Worked by supplementing standard 2D
video card.
• Did not do vertex transformations: these
were done in the CPU
• Did do texture mapping, z-buffering.
Rasterization
and
Interpolation
Primitive
Assembly
PCI
Raster
Operations
GPU
Frame
Buffer
• Main innovation: shifting the
transformation and lighting
calculations to the GPU
• Allowed multi-texturing: giving
bump maps, light maps, and
others..
• Faster AGP bus instead of PCI
Vertex
Transforms
AGP
Primitive
Assembly
Rasterization
and
Interpolation
GPU
Raster
Operations
Frame
Buffer
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Vertex
Transforms
AGP
For the first time, allowed limited amount
of programmability in the vertex pipeline
Also allowed volume texturing and multisampling (for antialiasing)
Primitive
Assembly
Rasterization
and
Interpolation
GPU
Small vertex
shaders
http://www.cis.upenn.edu/~suvenkat/700/
Raster
Operations
Frame
Buffer
• This generation is the first generation of
fully-programmable graphics cards
• Different versions have different resource
limits on fragment/vertex programs
Vertex
Transforms
AGP
Primitive
Assembly
Programmable
Vertex shader
Rasterization
and
Interpolation
Raster
Operations
Programmable
Fragment
Processor
Frame
Buffer
Not exactly a quantum leap, but…
• Simultaneous rendering to multiple buffers
• True conditionals and loops
• Higher precision throughput in the pipeline (64
bits end-to-end, compared to 32 bits earlier.)
• PCIe bus
• More memory/program length/texture accesses
Modeling
Transformations
Illumination
(Shading)
Viewing Transformation
(Perspective / Orthographic)
Clipping
Projection
(to Screen Space)
Scan Conversion
(Rasterization)
Visibility / Display
Modeling
Transformations
Illumination
(Shading)
Viewing Transformation
(Perspective / Orthographic)
Clipping
Projection
(to Screen Space)
Scan Conversion
(Rasterization)
Visibility / Display
• Primitives are processed in a series
of stages
• Each stage forwards its result on to
the next stage
• The pipeline can be drawn and
implemented in different ways
• Some stages may be in hardware,
others in software
• Optimizations & additional
programmability are available at
some stages
• Operate STRICTLY one vertex at a time.
• Take the original position of the vertex and
other properties (normal, color, lights, ...)
• Output the position and color of the vertex
after processing, any other changed
properties.
• Take a “primitive with adjacency” (so, more
than one vertex) plus other properties.
• Allow you to create new geometry from the
original adjacency information.
• Interpolate the vertices in a 2D primitive to fill
each pixel contained in the primitive.
• Texturing and many other kinds of
computation can be done.
• 3D models defined in their own
coordinate system (object
Illumination
(Shading)
space)
Viewing Transformation
(Perspective / Orthographic) • Modeling transforms orient the
models within a common
Clipping
coordinate frame (world space)
Modeling
Transformations
Projection
(to Screen Space)
Scan Conversion
(Rasterization)
Object space
Visibility / Display
World space
• Process one vertex at one time
– No information on other vertices
• Programmable
• Transformation
• Lighting
• Global to eye coordinate system
• Diffuse
• Specular
• Vertices lit (shaded) according to
material properties, surface
Illumination
properties (normal) and light
(Shading)
sources
Viewing Transformation
(Perspective / Orthographic) • Local lighting model
(Diffuse, Ambient, Phong, etc.)
Clipping
Modeling
Transformations
Projection
(to Screen Space)
Scan Conversion
(Rasterization)
Visibility / Display
• Maps world space to eye space
• Viewing position is transformed
Illumination
(Shading)
to origin & direction is oriented
Viewing Transformation
along some axis (usually z)
(Perspective / Orthographic)
Modeling
Transformations
Clipping
Eye space
Projection
(to Screen Space)
Scan Conversion
(Rasterization)
Visibility / Display
World space
Modeling
Transformations
• Transform to Normalized Device
Coordinates (NDC)
Illumination
(Shading)
Viewing Transformation
(Perspective / Orthographic)
Clipping
Projection
(to Screen Space)
Scan Conversion
(Rasterization)
Visibility / Display
Eye space
• Portions of the object
outside the view
volume
(view frustum)
are removed
NDC
• Backface culling
– Remove triangles facing away from view
– Eliminate ½ of the triangles in theory
• Clipping against view frustum
– Triangles may become quadrilaterals
• From floating point range [-1, 1] x [-1, 1] to
integer range [0, height-1] x [0, width-1]
Modeling
Transformations
Illumination
(Shading)
• The objects are projected to
the 2D image place (screen
space)
Viewing Transformation
(Perspective / Orthographic)
Clipping
Projection
(to Screen Space)
Scan Conversion
(Rasterization)
Visibility / Display
NDC
Screen Space
Modeling
Transformations
Illumination
(Shading)
Viewing Transformation
(Perspective / Orthographic)
Clipping
Projection
(to Screen Space)
Scan Conversion
(Rasterization)
Visibility / Display
• Rasterizes objects into pixels
• Interpolate values as we go
(color, depth, etc.)
•Fragment: corresponds to a
single pixel and includes color,
depth, and sometimes texturecoordinate values.
•Compute color and depth for
each pixel
•Most interesting part of GPU
•Optional
–(though hard to avoid)
•Cache data
–Hide latency from FB
•Sampling/filtering
–I told you this last time
Modeling
Transformations
Illumination
(Shading)
Viewing Transformation
(Perspective / Orthographic)
Clipping
Projection
(to Screen Space)
Scan Conversion
(Rasterization)
Visibility / Display
• Each pixel remembers the
closest object (depth buffer)
• Almost every step in the
graphics pipeline involves a
change of coordinate system.
Transformations are central to
understanding 3D computer
graphics.
the traditional pipeline
modeling
animation
rendering
motion
capture
image-based
rendering
the new pipeline?
3D
scanning
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