Computer Graphics Overview
Lecture 2
Nguyen Phan
What Will be Covered?
Image package
Photoshop
CAD package
Graphics Design
Applications
Computer Graphics
Auto CAD
Modeling package
3D Studio Max
Animation package
Flash, Digimation
3D Graphics
Video
Virtual
Reality
Animation
Visualization
Movie
Effects
Games
Algorithms
Research
Web Design
GAMES101 9 Lingqi Yan, UC Santa Barbara
Video Games
Sekiro: Shadows Die twice (2019 Game of the Year)
Video Games
Borderlan
1
d
0
s 3
(2019)
Movies
The Matrix (1999)
Movies
Avatar (2009)
Animations
Zootopia (2016)
Animations
Frozen 2
(2019)
Design
Autodesk Gallary
CG Photo
Design
Ikea - 75% of catalog is rendered imagery
Science, engineering, medicine, journalism, etc.
Visualization
Virtual Reality
Oculus VR
Augmented Reality
Microsoft Hololens
Simulation
The Dust Bowl phenomena Black hole from Interstellar
Graphical User Interfaces
Typography
The font Baskerville
The Quick Brown
Fox Jumps Over
The Lazy Dog
Why Study Computer
Graphics?
• Fundamental Intellectual Challenges
-
-
-
Creates and interacts with realistic virtual world
Requires understanding of all aspects of physical world
New computing methods, displays, technologies
Why Study Computer
Graphics?
• Technical Challenges
-
-
-
-
-
Introduction to CG
◼ Define Computer Graphics…
The technology associated with the use of
computer technology to convert created or
collected data into visual representations
Model
Rendering → focus of course
Display
Differences?
• Personal Understanding
Computer Graphics (Rendering)
MODEL IMAGE
Computer Vision
Computer Vision
(Image Processing)
(Not Comp.
Photography)
Computer Graphics
(Modeling, Simulation)
• No clear boundaries
Graphics Process
Rendering
transform,
Light,
Shade, &
Rasterize
Surface
Model
Image
Display
Geometric
Model
Scene
Model
Modeling
Geometry Modeling
â—¼ There are many ways to describe
geometry
â—¼ Explicit geometry:
Triangle meshes, Patches, Subdivision surfaces,…
â—¼ Implicit geometry:
Surface defined by x
2
+ y
2
+ z
2
= 10
Fractal sets, procedural definition, …
â—¼ Volume data
Samples from MRI, ultra-sound, simulation…
Example of Triangle Meshes
Making Models
Rendering
3D scanner
Computer vision
Model libraries
Interaction
Geometric
Modeling
Points, Lines,
Surfaces, …
Making Surface Models
Rendering
Scanner
Paint
Image libraries
Camera
Surface
Parameters
Color, BRDF,
Texture, Opacity, …
Rendering
Rendering
Transformation
Image generation
IG = (lighting, shading,
scan conversion)
Surface Model
Geometric Model
+
=
Image
Display
Image Display
Rendering
Image Representation
Pixel array,
Stroke list, NC cut list,
…
Optical Modulation
CRT, LED, LCD,
Plasma, Ink, Solid
material
Digital Images: pixels
Frame Buffer
Frame Buffer
A block of memory,
dedicated that contains the
pixel array to be passed to
the optical display system
Each pixel encodes color or
other properties (e.g.,
opacity)
Frame Buffer Concepts
Pixel: One element of frame buffer
- uniquely accessible point in image
Resolution: Width x Height (in pixels)
- 640x480, 1280x1024, 1920x1080
Color depth: Number of bits per-pixel in the buffer
- 8, 16, 24, 32-bits for RGBA
Buffer size: Total memory allocated for buffer
Frame Buffer Opacity
Alpha
Used for compositing or merging images
Alpha channel – added to color
Holds the alpha value for every pixel
8 bit range: 0 (transparent) – 255 (opaque)
How Much Memory?
For example:
If width=640, height=480, color depth=24 bits
Buffer size = 640 * 480 * 3 = 921,600 bytes
If width=1920, height=1080, color depth=24 bits
Buffer size = 1920 * 1080 * 3 = 6,220,800 bytes
Buffer size = width * height *color depth
Display Device
• CRT (Cathode Ray Tube)
• LED (Light Emitting Diode)
• Plasma, Projection, HMD, Volumetric
Important Features:
size, resolution, field of view, pixel-
pitch, color range, brightness,
refresh-rate, black level, update mode
(e.g., interlacing, …), distortion
Interaction
â—¼ Think about input devices in two ways:
Physical device – that can be described by
their real-world physical properties
(mouse, keyboard, joystick…)
Logical Device – application abstraction
â—¼ Interaction is an important component of
graphics applications
Physical Device
3D Interaction Device
Questions?
Watch for the first Homework, coming soon!
