Difference between Bresenham line DDA line

Bresenham Line Drawing Algorithm

1. Bresenham line drawing algorithm is used with fixed point i.e. integer arithmetic.
2. Bresenham line drawing algorithm uses subtraction and addition in its operators.
3. It is faster than DDA.
4. Bresenham line drawing algorithm is more efficient and more accurate than DDA line drawing algorithm.
5. It is less expensive.
6. Does not round off but takes the increment value in its operation.

DDA (Digital differential analyze) Line Drawing Algorithm

1. DDA line drawing algorithm is used with floatinf point e.i. real arithmetic.
2. DDA line drawing algorithm uses multiplication and division in its operators.
3. DDA line drawing algorithm slower than bresenham line drawing algorithm.
4. DDA line drawing algorithm  is not as accurate and efficient as bresenham 
5.  It is expensive.
6. Round off the coordinate to integer that is nearest to the line.

Difference between Beam penetration and Shadow mask

Beam Penetration Method

1. These method  is used in  Random scan system to display color.
2. It can display only four color like red , green , orange , yellow.
3. Less color are available because color in beam penetration depend on the speed of electron beam.
4. Less expensive.
5. Quality of picture is not good.
6. High Resolution.

Shadow Mask Method

1. These method is used in Raster scan system to display color.
2. It can display millions of colors.
3. Millions color are available because color in shadow mask depend on the type of the ray.
4. More expensive.
5. Quality of picture is good .
6. Low resolution.

Difference between Raster scan and Random scan

Raster scan display 

1. Raster scan display has ability to display area filled with solid color or pattern.
2. It is used interlacing. 
3. In raster scan display , beam is  moved all over the screen one scan line at a time top to bottom and back to top.
4. Lower resolution.
5. Less Expensive.
6. Refresh rate is independent of picture complexity.
7. Editing is difficult.
8. Scan conversion is not required.
9. Raster scan display can display mathematically smooth line .
10. Raster scan display is used  in Shadow mask CRT.

                                    

Random scan display 

1. In random scan display only draw line and character. It is also used vector scan display.
2. Does not interlacing.
3. In random scan display the beam is moved between the end point of the graphics primitive.
4. High Resolution.
5. More Expensive.
6. Refresh rate is dependent of picture complexity.
7. Editing is easy.
8. scan conversion is required.
9. Random scan display draw continuous smooth line.
10. Random scan display is used in Beam penetration. 

Introduction Computer Graphics

 Introduction Computer Graphics 

Computer graphics is a method and technique for generating and manipulating image on a computer. Another definition " computer graphics is pictorial representation of data."
 Computer graphics is an art of drawing , picture , line , chart etc. using computer with the help of programming . Computer graphic is made of number of pixels. Pixel is the smallest unit of the computer screen .

Types of computer graphics

Basically two types of computer graphics.

Interactive Computer graphics :- Interactive computer graphics involves a two way communication between computer and user . In this computer graphics , the graphics responds to what the user does do it . It can be as simple as changing color when the user moves his mouse over it or it can be a full on graphics animation when the user click on it.

Non Interactive computer graphics :- Non Interactive graphics , user does not interact with computer graphics . In this computer graphics in which user does not have any kind of control over the image . Image is static stored program and will work according to the instruction given in the program .

Application of compute graphics 

1. Computer Aided Design :- CAD used in design of building , automobile , aircraft , watercraft , spacecraft and many other product. Object are display in wire frame outline . Software package provide multi window environment . Provide standard shape and provide animation.

2. Presentation Graphics :- Used to produce illustration for report and generate slide for use with projectors .Commonly used to summarize financial , statistical , scientific economic data for research report. Provide bar-charts , line-graph , pie-chart , surface-graph , time chart.

3. Computer art :- Used in fine art and commercial art. Provide paint brush package and animation package .These package facilities for designing object shapes and object motion . Example is cartoon drawing , painting , product advertising logo design.

4.Entertainment :- Used in motion pictures , music , vedio and telivision  show . Also used in making of cartoon animation film and game industry.

5. Education and Training :- Computer graphics provide models of physical physiological and equipment such as color coded diagram to help trainers understand the operation of system .

6. Visualization :- Provide scientific visualization and business visualization .