Computer Graphics
Lecture 3
Draw Circle
A Simple Circle Drawing
Algorithm
The equation for a circle is:
x2 + y 2 = r 2
where r is the radius of the circle
So, we can write a simple circle
drawing algorithm by solving the
equation for y at unit x interv
Computer Graphics
Lecture 4
Filling
Filling Polygons
So we can figure out how to draw lines
and circles
How do we go about drawing polygons?
We use an incremental algorithm known
as the scan-line algorithm
Filling Polygons
Three types of polygons
1. Si
Computer Graphics
Viewing In 2D
2
of
30
Viewing in 2D
250
45
Window in world coordinates.
Viewport in
Device coords
250 x 250
Pixels.
3
of
30
Viewing in 2D
In 2D, a world consists of an infinite plane, defined in
world coordinates, i.e metres, angstroms
Computer Animation
Animation
Animate = to give life to
Specify, directly or indirectly, how thing moves
in time and space
Angel Games
Applications
Special Effects (Movies, TV)
Video Games
Virtual Reality
Simulation, Training, Military
Medical
Robotics,
Computer Graphics
Projections
3D Viewing
Inherently more complex than 2D case.
Most display devices are only 2D
Need to use a projection to transform 3D
object or scene to 2D display device.
2
Jetty at Margate England, 1898.
http:/brightbytes.com/cosit
Introduction
Computer Graphics
AlexandriaUniversityComputerSciencedepartment
Dr.YasserFouad
Why Study Computer Graphics?
Graphics is cool
I like to see what Im doing
I like to show people what Im doing
Graphics is interesting
Involves simulation, AI,
1
of
32
Graphic Hardware
Lecture 9
2
of
32
Architecture of Graphics System
Display
Processor
Memory
CPU
Display
Processor
System Bus
Frame
Buffer
System
Memory
Video
Controller
Monitor
3
of
32
IBM Advances in
Display Technology
In 1981, IBM introduced th
Computer Graphics
Transformations
Transformations.
What is a transformation?
P =T(P)
What does it do?
Transform the coordinates / normal vectors of
objects
Why use them?
Modelling
-Moving the objects to the desired location in the environment
-Multiple