Lesson 3 (Computer Graphics)

computer graphics

produced using the computers

Computer Graphics

Image Display

Graphics

Applications and Importance of Computer Graphics in Various Fields

computer graphics

can be static images (steady pictures) or dynamic moving images

Image Display

Images conveys a lot of information content both in terms of information theory (number of bits to represent an image) and semantics (meaning behind the image)

Graphics

Image came from the word graphikos (γραφικός), that refers to "belonging to drawing" or "pertaining to drawing." Its rooted to another Greek word graphē (γραφή), refers to "drawing" or "writing."

Display Information

Design

User Interface

Simulation

Applications of Computer Graphics into Four Main Areas

Computational Biology

Computational Physics

Information of Graphics

Scientific Visualization

4 Display Information

Computational Biology

Mainly focus on developing mathematical models and computational simulation techniques from computer science to address biological problems.

Computational Physics

Involves examination and implementation of numerical algorithms to solve problems in physics. Sometimes regarded as intermediate branch between theoretical and experimental physics.

Information Graphics

Also known as infographics, are visual representation of data. It is used to explain complex information clearly and easily in technical writing. Considered a valuable tool for computer scientist, mathematician, and statistician to communicate conceptual information.

Scientific Visualization

It uses computer graphics to visually represent 3D phenomena like architectural, meteorological, medical, and biological systems, helps to understanding complex numerical representation of scientific concepts and results.

Graphic Design

Computer-Aided Design

Web Design

3 Design

Graphic Design

It compose of various artistic and professional disciplines focusing the communication, using symbols, images, and words to present an idea or convey a message. It refers to both design process and designs.

Computer-Aided Design

Uses computer technology to design objects focusing on geometric models for 2D and 3D designs. It is often used for special effects in movies, advertising, and technical manuals.

Web Design

Skills of designing a content presentation that is delivered through web browser. This involves multiple disciplines like graphic design, human-computer interaction, and search engine optimization.

Digital Art

Video Game

Virtual Reality (VR)

3 User Interface

Digital Art

Mainly refers to an art created on a computer in digital form. This creation transformed traditional art forms to a new practices like net art or virtual reality.

Video Game

Electronic games where users interact with a user interface to generate visual feedback. These are played on electronic systems known as platforms that relies on graphic.

Virtual Reality (VR)

Allows user to interact with computer-simulated environment that mimics the real world. Creating a high-fidelity _____ experience is challenging due to technical limitations.

Virtual Reality (VR)

This is associated with immersive, highly visual, and 3D environment.

Computer Simulation

Education

Information Visualization

3 Simulation

Computer Simulation

Also known as computational model or computer model, that attempts to mimic an abstract model of a particular system.

Education

Simulation are useful for mathematical modeling in physics, biology, psychology, social science, and engineering by providing insights to system operations and behaviour.

Information Visualization

This is visually representing large collections of non-numerical information and using graphical techniques to help people understand and analyze the data.

Display Devices

is an output devices

Display devicess

are used to present the information in visual forms. Display system are mostly called a video monitor or video display unit (VDU).

Cathode-Ray Tube (CRT)

This uses a vacuum tube and electron gun that starts when the cathode is heated to emit electrons which turned into a beam using electron gun. It collides and deflect then struck a phosphor (a tiny dot coated with red, green, and blue phosphor). The intensity of beam determines the brightness of each dot.

Electron Gun

Focusing and Accelerating Anodes

Phosphorus-coated Screen

Horizontal and Vertical Deflection Plates

4 Components of CRT

Electron Gun

It is made of several elements for heating filament (heater) and cathode. Electron gun is used as source of electrons focusing a narrow beam facing the CRT.

Focusing and Accelerating Anodes

This are used to produce the narrow and sharp beam of electrons

Horizontal and Vertical Deflection Plates

These plates are used to guide the path of beam, this produce an electromagnetic field that bends the electron beam through as it travels.

Phosphorus-coated screen

This is used to produce bright spots when accelerated electron beam hits it.

Raster Scan or Vector Scan

Two ways to present an object to the screen

RASTER SCAN

A scanning technique where the electron beam was sweep throughout the CRT screen. The object displayed was converted into pixels, which the information is stored in the frame buffer. As the electron beams sweep downward, the intensity of beam is modified based in the information stored in the buffer in a rapid process.

RANDOM SCAN OR VECTOR SCAN (STROKE-WRITING DISPLAY)

A scanning technique where the image is defined and set in line segments or vector, unlike raster, it does not use the frame buffer. But rather, it directly interpret the display and draw the image, this is processed so fast that it must not look like it flickers.

random scan

more complex than the raster scan.

Color CRT Monitor

Similar with CRT, but, the CRT is a monochrome type of monitor. It only has a single electron gun and phosphorus layer which only emits one color.

Color CRT

While, the _______, has three electron gun, phosphorus dot triad (phosphorus dot arranged in triad, a shadow mask (metal plate with tiny holes) or aperture wire place

between the electron guns and the phosphorus screen to strike only the correct color of the phosphorus dot.

Color CRT Monitor

The _____ can produce full-color image while standard CRT can only display one color.

BEAM-PENETRATION METHOD

SHADOW-MASK METHOD

Two Basic Color Display Techniques

BEAM-PENETRATION METHOD

It is used with a random scan monitor to display containing two phosphorus layers (Red and Green). The color is shown based on the penetration of the phosphorus layer (Red/ Green).

SHADOW-MASK METHOD

It is used with a raster scan monitor to display and having more colors than beam- penetration. The three phosphorus dot are arrange in triad red, green, and blue.

Liquid Crystal Display (LCD)

This monitor which determines the brightness level in AC power. Each spot has three tiny dot colored filters (red, green, blue) to form a picture. These are made with the mixture of solid and liquid, therefore when current flows inside, its position change to display the desired color.

Liquid Crystal Display (LCD)

It is a super precise light-controlling screen to create an image.

Light Emitting Diode (LED)

A type of device the emits when an electricity passes through, it is a semiconductor device. The _____ is so small that it can easily make any display unit by arranging the large number of ____.

Light Emitting Diode (LED)

These are commonly used in smartphones, TV, traffic lights, and others. It is also very energy-efficient, bright, and colorful.

Direct View Storage Tube (DVST)

A display technology that uses a storage mesh to hold the image pattern, the flood gun continuously illuminate the charged areas to the mesh displaying the image without refreshing.

Direct View Storage Tube (DVST)

This devices are monochrome and limited to dynamic functions.

Plasma Display

This display device works by ionizing a gas mixture to the tiny cells to create a UV light and excites the phosphorus to produce visible light. This device requires more power and prone to burn-in.

Anode

Cathode

Gas Plates

Fluorescent Cells

4 Components of Plasma Display

Anode

This is used to deliver positive voltage and it has a line wires.

Cathode (fine wires)

This is used to deliver negative voltage gas cells.

Gas Plates

This works like a capacitor, when the voltage passes, the cells lights regularly.

Fluorescent Cells

It contains a small pocket with gas liquids, it only emits light when the voltage passes through the neon gas.

3D Display

This is also called stereoscope display that is capable of bringing depth perception to the viewer.

Example: Holographic Display and Retina Display

Display Controller (Video Controller)

This is used to control the operations of the display device.

Display File Memory

It is used to create an image by using visual recognition.

Open Graphics Library (OpenGL )

is a cross-language and a cross-platform API used for rendering 2D or 3D Vector Graphics. As it serves as a software interface to graphics hardware that allows the developers to create a complex 3D scenes from simple primitives.

GL_POINTS

GL_LINES

GL_LINES_STRIP

GL_LINE_LOOP

GL_TRIANGLES

GL_TRIANGLE_STRIP

GL_TRIANGLE_FAN

GL_QUADS

GL_QUAD_STRIP

GL_POLYGON

OpenGL Primitives

GL_POINTS

Renders each vertex as a single point. Useful for scatter plots or particle systems.

GL_LINES

Draws a separate line segment between each pair of vertices. Requires an even number of vertices. Good for drawing disconnected lines.

GL_LINE_STRIP

Draws a connected series of line segments. Each vertex (except the first) is connected to the previous one. Useful for drawing continuous lines or graphs.

GL_LINE_LOOP

Similar to GL_LINE_STRIP, but the last vertex is also connected to the first, forming a closed loop. Good for drawing outlines of shapes.

GL_TRIANGLES

Draws a separate triangle for each group of three vertices. Requires the number of vertices to be a multiple of three. The most common primitive for creating 3D models.

GL_TRIANGLE_STRIP

Draws a series of connected triangles. Each triangle shares an edge with the previous triangle. More efficient than GL_TRIANGLES for drawing complex surfaces.

GL_TRIANGLE_FAN

Draws a series of connected triangles that share a common vertex. Good for creating cones or disks.

GL_QUADS

Draws a separate quadrilateral (four-sided polygon) for each group of four vertices. Requires the number of vertices to be a multiple of four.

GL_QUAD_STRIP

Draws a series of connected quadrilaterals. Each quad shares an edge with the previous quad.

GL_POLYGON

Draws a single polygon using the provided vertices. However, its use is discouraged as it may not be supported by all OpenGL implementations, and its behavior with non-convex polygons is undefined. It's generally better to use triangles instead.

OpenGL Utility Toolkit (GLUT)

is a library utilities for OpenGL Programs, designed to simplify tasks such as window creation, input handling, and event processing. It provides basic framework for creating OpenGL applications, hiding the complexity of platform-specific details of window management and user interaction.

GLUT

Thus, ____ makes an easier to write portable OpenGL code without modification.

OpenGL Utility Library (GLU)

is a set of functions to create texture mipmaps from a base image, map coordinates between screen and object space, and draw quadric surfaces and NURBS

OpenGL Mathematics (GLM)

is a C++ mathematics library for 3D software based on the

OpenGL Shading Language (GLSL) specification.