Computer Graphics AND Multimedia: ETCS 257

LAB MANUAL
COMPUTER GRAPHICS
AND
MULTIMEDIA
ETCS 257
Maharaja Agrasen Institute of Technology,

PSP area, Sector – 22, Rohini, New Delhi – 110085
(Affiliated to Guru Gobind Singh Indraprastha, New Delhi)
MAIT/CSE 1|Page
CONTENTS
1. Introduction to the lab
2. Lab requirements (details of H/W & S/W to be used)
3. List of experiments (as per syllabus prescribed by G.G.S.I.P.U)
4. List of experiments (beyond the syllabus prescribed by G.G.S.I.P.U)
5. Format of lab record to be prepared by the students.
6. Marking scheme for the practical exam
7. Details of different section along with examples & expected viva questions.
MAIT/CSE 2|Page
1. INTRODUCTION TO COMUTER GRAPHICS
What is computer graphics?
• Computer graphics deals with all aspects of creating images with a computer
Hardware
Software
Applications
Computer graphics are graphics created using computers and, more generally, the representation
and manipulation of image data by a computer. The development of computer graphics, or
simply referred to as CG, has made computers easier to interact with, and better for
understanding and interpreting many types of data. Developments in computer graphics have had
a profound impact on many types of media and have revolutionized the animation and video
game industry. Typically, the term computer graphics refers to several different things: · the
representation and manipulation of image data by a computer · the various technologies used to
create and manipulate images · the images so produced and The subfield of computer science
which studies methods for digitally synthesizing and manipulating visual content Applications: ·
Computer Aided Design · Computer simulation · Digital art · Education · Graphic design ·
Information visualization · Scientific visualization · Video Games · Virtual reality · Web design
Graphics mode Initialization
First of all we have to call the initgraph function that will intialize the graphics mode on the
computer. initigraph have the following prototype. void initgraph(int far *graphdriver, int far
*graphmode, char far *pathtodriver); Initgraph initializes the graphics system by loading a
graphics driver from disk (or validating a registered driver) then putting the system into graphics
mode. Initgraph also resets all graphics settings (color, palette, current position, viewport, etc.) to
their defaults, then resets graphresult to 0.
*graphdriver Integer that specifies the graphics driver to be used. You can give graphdriver a
value using a constant of the graphics_drivers enumeration type.
*graphmode Integer that specifies the initial graphics mode (unless *graphdriver = DETECT).
If *graphdriver = DETECT, initgraph sets *graphmode to the highest resolution available for the
detected driver. You can give *graphmode a value using a constant of the graphics_modes
enumeration type.
MAIT/CSE 3|Page
*pathtodriver Specifies the directory path where initgraph looks for graphics drivers (*.BGI)
first.
1. If they‟re not there, initgraph looks in the current directory.
2. If pathtodriver is null, the driver files must be in the current directory.
*graphdriver and *graphmode must be set to valid graphics_drivers and graphics_mode values or
you‟ll get unpredictable results. (The exception is graphdriver = DETECT.) After a call to
initgraph, *graphdriver is set to the current graphics driver, and *graphmode is set to the current
graphics mode. You can tell initgraph to use a particular graphics driver and mode, or to
autodetect the attached video adapter at run time and pick the corresponding driver. If you tell
initgraph to autodetect, it calls detectgraph to select a graphics driver and mode.
Basic Function : Cleardevice() Clears all previous graphical outputs generated by the previous
programs.Its a good practice to include this method at the starting of each program. cleardevice()
gotoxy() This will initialize the graphics cusor to the specified co-ordiante.In C gotoxy function
is used very frequently to locate the cursor at different locations whenever as necessary. Syntax :
gotoxy(x,y)
putpixex() It will colour the pixel specified by the co-ordinates.
Syntax: putpixel(x,y,WHITE)
outtextxy() This method is used to display a text in any position on the screen.The numeric
coordinates are substituted for x and y. Syntax: outtextxy(x,y,"HELLO") rectangle() Draws a
rectangle according to the given parameter x and y are the top-left corner co-ordinates. Syntax :
rectangle(int left, int top, int right, int bottom)
circle() Draws a circle with x,y as the center . Syntax: circle(x,y,radius)
line() Draws a line as per the given co-ordinates. Syntax : line(int startx, int starty, int endx, int
endy)
moveto() Cursor is moved from the current location to the specified location dx,dy.These
parameters can also be used as incremental values. Syntax : moveto(dx,dy)
lineto() Draws a line from its current location to the co-ordinate(x,y) Syntax : lineto(x,y)
ellipse() Draws the ellipse with the specified angles and coordinates. Syntax : ellipse(x-centre,y-
center,starting_angle,ending_angle,x_radius,y_radius)
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drawpoly() Draws a polygon with (num_of_points +1) edges.The array 'points' int points[
]=(x1,y1,x2,y2,x3,y3...) Syntax : drawpoly(num_of_points + 1, points) settextstyle() The fonts
available are :TRIPLEX_FONT, SMALL_FONT SANS_SERIE_FONT, GOTHIC_FONT
The direction can be changed as HORIZ_DIR or VERT_DIR, The charecter size increases from
1 to 10 Syntax : settextstyle(DEFAULT_FONT,HORIZ_DIR,1)
setfillstyle() The fill styles avaliable are SOLID_FILL, LINE_FILL, HATCH_FILL,
SLASH_FILL etc. Syntax : setfillstyle(SOLID_FILL,RED)
setcolor() Sets the color
Syntax : setcolor(color_name)
delay() Cause a pause in execution of the program 1000ms= 1 second Syntax : delay(100)
closegraph() Terminates
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2. LAB REQUIREMENTS
Software requirements: Turbo C++ or Turbo C compiler, MAYA
Operating System: Windows XP (SP2)
Hardware requirements:
Windows and Linux: Intel 64/32 or AMD Athlon 64/32, or AMD Opteron processor
2 GB RAM
2 GB hard disk space
Qualified hardware-accelerated OpenGL graphics card
MAIT/CSE 6|Page
3. LIST OF EXPERIMENTS
(As prescribed by G.G.S.I.P.U)
COMPUTER GRAPHICS & MULTIMEDIA LAB
Paper Code: ETCS-257 L T C

Paper: Computer Graphics & Multimedia Lab 0 2 1
List of Experiments:
1. Study of Fundamental Graphics Functions.
2. Implementation of Line drawing algorithms: DDA Algorithm, Bresenham's Algorithm
3. Implementation of Circle drawing algorithms: Bresenham's Algorithm, Mid-Point

Algorithm.
4. Programs on 2D and 3D transformations
5. Write a program to implement Cohen Sutherland line clipping algorithm
6. Write a program to draw Bezier curve.
7. Using Flash/Maya perform different operations (rotation, scaling move etc..) on objects
8. Create a Bouncing Ball using Key frame animation and Path animation.
NOTE: - At least 8 Experiments out of the list must be done in the semester.
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4. LIST OF EXPERIMENTS
(Beyond the syllabus prescribed by G.G.S.I.P.U)

Course Code: ETCS-257 L T C
Paper: Computer Graphics & Multimedia Lab 0 2 1
List of Experiments
1. To Study various in build graphics functions in C library.

2. Write a program to draw a line using DDA algorithm.
3. Write a program to draw a line using Bresenham‘s algorithm.
4. Write a program to draw a circle using midpoint algorithm.
5. Write a program to draw a circle using Bresenham‘s algorithm.
6. Write a program to draw a rectangle using line drawing algorithm.
7. Write a program to perform 2D Transformation on a line.
8. Write a program to perform shear transformation on a rectangle.
9. Write a program to rotate a circle (alternatively inside and outside) around the
circumference of another circle.
10. Write a program to draw a car using in build graphics function and translate it from
bottom left corner to right bottom corner of screen.
11. Write a program to draw balloons using in build graphics function and translate it
from bottom left corner to right top corner of screen.
12. Write a program to draw a cube using in build library function and perform 3D
transformations
i) Translations in x, y, z directions
ii) Rotation by angle 450 about z axis, rotation by 600 about y-axis in succession.
iii) Scaling in x-direction by a factor of 2, scaling in y- direction by a factor of 3.
12. Write a program to implement line clipping (Cohen Sutherland algorithm).
13. Write a program for making Bezier curve.
14. Write a program to study various in build functions for 2D drawing in MAYA
software.
15. Write a program to show animation of a ball moving in a helical path.
16. Write a program to show animation of solar system.
MAIT/CSE 8|Page
5. FORMAT OF THE LAB RECORD TO BE
PREPARED BY THE STUDENTS
1. The front page of the lab record prepared by the students should have a cover
page as displayed below.
NAME OF THE LAB

Font should be (Size 20‖, italics bold, Times New Roman)
Faculty name Student name Font

should be (12‖, Times Roman) Roll No.:
Semester:
Group:
Font should be (12‖, Times Roman)
Maharaja Agrasen Institute of Technology, PSP Area,

Sector – 22, Rohini, New Delhi – 110085
Font should be (18‖, Times Roman)
MAIT/CSE 9|Page
2. The second page in the record should be the index as displayed below.
PRACTICAL RECORD
PAPER CODE : ETCS - 257
Name of the student :
University Roll No. :
Branch :
Section/ Group :
PRACTICAL DETAILS
a) Experiments according to the list provided by GGSIPU
Exp. no Experiment Name Date of Date of Remarks Marks

performance checking (10)
MAIT/CSE 10 | P a g e
Exp. no Experiment Name Date of Date of Remarks Marks
performance checking (10)
6. MARKING SCHEME FOR THE PRACTICAL EXAMS
There will be two practical exams in each semester.
 Internal Practical Exam

 External Practical Exam
INTERNAL PRACTICAL EXAM
It is taken by the concerned lecturer of the batch.
MARKING SCHEME FOR THIS EXAM IS:
Total Marks: 40
Division of 40 marks is as follows
1. Regularity: 25
 Performing program in each turn of the lab

 Attendance of the lab
 File
2. Viva Voice: 10
3. Project: 5
NOTE: For the regularity, marks are awarded to the student out of 10 for each
experiment performed in the lab and at the end the average marks are
giving out of 25.
EXTERNAL PRACTICAL EXAM
It is taken by the concerned lecturer of the batch and by an external examiner. In this exam
student needs to perform the experiment allotted at the time of the examination, a sheet will
be given to the student in which some details asked by the examiner needs to be written and
at the last viva will be taken by the external examiner.
MARKING SCHEME FOR THIS EXAM IS:
Total Marks: 60
Division of 60 marks is as follows
a. Sheet filled by the student: 20
b. Viva Voice: 15
c. Experiment performance: 15
d. File submitted: 10
NOTE:
 Internal marks + External marks = Total marks given to the students

(40 marks) (60 marks) (100 marks)
 Experiments given to perform can be from any section of the lab.
7. DETAILS OF DIFFERENT SECTION
WITH EXAMPLES
&
EXPECTED VIVA QUESTIONS
BASIC GRAPHICS FUNCTION
1) INITGRAPH
 Initializes the graphics system.
Declaration
 Void far initgraph(int far *graphdriver)
Remarks
 To start the graphic system, you must first call initgraph.
 Initgraph initializes the graphic system by loading a graphics driver from disk (or validating a registered
driver) then putting the system into graphics mode.
 Initgraph also resets all graphics settings (color, palette, current position, viewport, etc) to their defaults
then resets graph.
2) GETPIXEL, PUTPIXEL
 Getpixel gets the color of a specified pixel.
 Putpixel places a pixel at a specified point.
Decleration
 Unsigned far getpixel(int x, int y)
 Void far putpixel(int x, int y, int color)
Remarks
 Getpixel gets the color of the pixel located at (x,y);
 Putpixel plots a point in the color defined at (x, y).
Return value
 Getpixel returns the color of the given pixel.
 Putpixel does not return.
3) CLOSE GRAPH
 Shuts down the graphic system.
Decleration
 Void far closegraph(void);
Remarks
 Close graph deallocates all memory allocated by the graphic system.
 It then restores the screen to the mode it was in before you called initgraph.
Return value
 None.
4) ARC, CIRCLE, PIESLICE

 arc draws a circular arc.
 Circle draws a circle
 Pieslice draws and fills a circular pieslice
Decleration
 Void far arc(int x, int y, int stangle, int end_angle, int radius);
 Void far circle(int x, int y, int radius);
 Void far pieslice(int x, int y, int stangle, int end_angle, int radius);
Remarks
 Arc draws a circular arc in the current drawing color
 Circle draws a circle in the current drawing color
 Pieslice draws a pieslice in the current drawing color, then fills it using the current fill pattern and fill color.
5) ELLIPSE, FILLELIPSE, SECTOR

 Ellipse draws an elliptical arc.
 Fillellipse draws and fills ellipse.
 Sector draws and fills an elliptical pie slice.
Decleration
 Void far ellipse(int x, int y, int stangle, int end_angle, int xradius, int yradius)
 Void far fillellipse(int x, int y, int xradius, int yradius)
 Void farsectoe(int x, int y, int stangle, int end_angle, int xradius, int yradius)
Remarks
 Ellipse draws an elliptical arc in the current drawing color.
 Fillellipse draws an elliptical arc in the current drawing color and than fills it with fill color and fill pattern.
 Sector draws an elliptical pie slice in the current drawing color and than fills it using the pattern and color
defined by setfillstyle or setfillpattern.
6) FLOODFILL
 Flood-fills a bounded region.
Decleration
 Void far floodfill(int x, int y, int border)
Remarks
 Floodfills an enclosed area on bitmap device.
 The area bounded by the color border is flooded with the current fill pattern and fill color.
 (x,y) is a ―seed point‖
 If the seed is within an enclosed area, the inside will be filled.
 If the seed is outside the enclosed area, the exterior will be filled.
 Use fillpoly instead of floodfill wherever possible so you can maintain code compatibility with future
versions.
 Floodfill doesnot work with the IBM-8514 driver.
Return value
 If an error occurs while flooding a region, graph result returns ‗1‘.
7) GETCOLOR, SETCOLOR
 Getcolor returns the current drawing color.
 Setcolor returns the current drawing color.
Decleration
 Int far getcolor(void);
 Void far setcolor(int color)
Remarks
 Getcolor returns the current drawing color.
 Setcolor sets the current drawing color to color, which can range from 0 to getmaxcolor.
 To set a drawing color with setcolor , you can pass either the color number or the equivalent color name.
8) LINE, LINEREL, LINETO

 Line draws a line between two specified pints.
 Onerel draws a line relative distance from current position(CP).
 Linrto draws a line from the current position (CP) to(x,y).
Decleration
 Void far lineto(int x, int y)
Remarks
 Line draws a line from (x1, y1) to (x2, y2) using the current color, line style and thickness. It does not
update the current position (CP).
 Linerel draws a line from the CP to a point that is relative distance (dx, dy) from the CP, then advances the
CP by (dx, dy).
 Lineto draws a line from the CP to (x, y), then moves the CP to (x,y).
Return value
 None
9) RECTANGLE
 Draws a rectangle in graphics mode.
Decleration
 Void far rectangle(int left, int top, int right, int bottom)
Remarks
 It draws a rectangle in the current line style, thickness and drawing color.
 (left, top) is the upper left corner of the rectangle, and (right, bottom) is its lower right corner.
DDA Algorithm for line drawing.
 Start.
 Declare variables x,y,x1,y1,x2,y2,k,dx,dy,s,xi,yi and also declare gdriver=DETECT,gmode.
 Initialize the graphic mode with the path location in TC folder.
 Input the two line end-points and store the left end-points in (x1,y1).
 Load (x1,y1) into the frame buffer; that is, plot the first point. Put x=x1,y=y1.
 Calculate dx=x2-x1 and dy=y2-y1.
 If abs(dx) > abs(dy), do s=abs(dx).
Otherwise s= abs(dy).
 Then xi=dx/s and yi=dy/s.
 Start from k=0 and continuing till k<s,the points will be
o x=x+xi.
o y=y+yi.
 Place pixels using putpixel at points (x,y) in specified colour.
 Close Graph.
 Stop.
Bresenham’s algorithm for line drawing.
 Start.
 Declare variables x,y,x1,y1,x2,y2,p,dx,dy and also declare gdriver=DETECT,gmode.
 Initialize the graphic mode with the path location in TC folder.
 Input the two line end-points and store the left end-points in (x1,y1).
 Load (x1,y1) into the frame buffer; that is, plot the first point put x=x1,y=y1.
 Calculate dx=x2-x1 and dy=y2-y1,and obtain the initial value of decision parameter p as:
 p=(2dy-dx).
 Starting from first point (x,y) perform the following test:
 Repeat step 9 while(x<=x2).
 If p<0,next point is (x+1,y) and p=(p+2dy).
 Otherwise, the next point to plot is (x+1,y+1) and p=(p+2dy-2dx).
 Place pixels using putpixel at points (x,y) in specified colour.
 Close Graph.
 Stop
Algorithm to Clip a Line.
 Start.
 Initialize the graphic system using initgraph function.
 Get the input of window coordinates from the user and draw a window.
 Get the input of line coordinates from user and draw the line.
 Calculate the region code of each end point of line using relation given in steps 6 to step
 Let (x,y) be the coordinates of end point of line and (xmin,ymin), (xmax,ymax) be coordinates of world
window
 If y –ymax = +ve
 MSB region code = 1.
 Else MSB region code = 0.
 If ymin – y = +ve
 Region code = 1.
 Else Region code = 0.
 If x – xmax = +ve
 Region code = 1.
 Else Region code = 0.
 If xmin – x = +ve
 LSB Region code = 1.
 Else LSB Region code = 0.
 Calculate region code of both end points.
 Logically and both region code.
 If Logically anded result is = 0
 Line is not a clipping candidate.
 Else.
 Line is a clipping candidate.
 Calculate slope of line using formula slope=(y2-y1)/(x2-x1).
 If line is to be horizontally clipped.
 New y = ymin or ymax.
 New x = x1 + ((new y - y1)/slope).
 If line is to be vertically clipped.
 New x = xmin or xmax.
 New y = y1+slope*(new x –x1).
 Clip the lines from these intersection points.
 Display the new line.
 Close the graphic system. Stop.
 Sample Code
A C++ program to draw a line using Bresenham's Line Algorithm (BLA) for
lines with slopes negative and less than 1.
# include <iostream.h>
# include <graphics.h>
# include <conio.h>
# include <math.h>
void show_screen( );
void bresenham_line(const int,const int,const int,const int);
int main( )
{
int driver=VGA;
int mode=VGAHI;
int x_1=0;
int y_1=0;
int x_2=0;
int y_2=0;
do
{
show_screen( );
gotoxy(8,10);
cout<<"Coordinates of Point-I (x1,y1) :";
gotoxy(8,11);
cout<<"ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ";
gotoxy(12,13);
cout<<"Enter the value of x1 = ";
cin>>x_1;
gotoxy(12,14);
cout<<"Enter the value of y1 = ";
cin>>y_1;
gotoxy(8,18);
cout<<"Coordinates of Point-II (x2,y2) :";
gotoxy(8,19);
cout<<"ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ";
gotoxy(12,21);
cin>>x_2;
gotoxy(12,22);
cin>>y_2;
initgraph(&driver,&mode,"..\\Bgi");
setcolor(15);
bresenham_line(x_1,y_1,x_2,y_2);
setcolor(15);
outtextxy(110,460,"Press <Enter> to continue or any other key to exit.");
int key=int(getch( ));
if(key!=13)
break;
}
while(1);
return 0;
}
void bresenham_line(const int x_1,const int y_1,const int x_2,const int y_2)
{
int color=getcolor( );
int x1=x_1;
int y1=y_1;
int x2=x_2;
int y2=y_2;
if(x_1>x_2)
{
x1=x_2;
y1=y_2;
x2=x_1;
y2=y_1;
}
int dx=abs(x2-x1);
int dy=abs(y2-y1);
int two_dy=(2*dy);
int two_dy_dx=(2*(dy-dx));
int p=((2*dy)-dx);
int x=x1;
int y=y1;
putpixel(x,y,color);
while(x<x2)
{
x++;
if(p<0)
p+=two_dy;
else
{
y++;
p+=two_dy_dx;
}
}
}
void show_screen( )
{
restorecrtmode( );
textmode(C4350);
cprintf("\n*********************************************************");
cprintf("*************************- -***********************");
cprintf("*------------------------- ");
textbackground(1);
cprintf(" Bresenham's Line Algorithm ");
textbackground(8);
cprintf(" -----------------------*");
cprintf("*-***********************- -*********************-*");
cprintf("*-*********************************************************-*");
for(int count=0;count<42;count++)
cprintf("*-* *-*");
gotoxy(1,46);
cprintf("*- ********************************************************-*");
cprintf("*------------------------------------------------------------------------------*");
cprintf("***********************************************");
gotoxy(8,40);
cout<<"Note :";
gotoxy(8,41);
cout<<"ÍÍÍÍÍÍ";
gotoxy(12,43);
cout<<"The slope of the line should be negative and less than 1.";
gotoxy(1,2);
}
lines with slopes negative and greater than 1.
# include <conio.h>
# include <math.h>
int main( )
{
int driver=VGA;
int mode=VGAHI;
int x_1=0;
int y_1=0;
int x_2=0;
int y_2=0;
do
{
show_screen( );
gotoxy(8,10);
gotoxy(8,11);
gotoxy(12,13);
cin>>x_1;
gotoxy(12,14);
cin>>y_1;
gotoxy(8,18);
gotoxy(8,19);
gotoxy(12,21);
cin>>x_2;
gotoxy(12,22);
cin>>y_2;
setcolor(15);
setcolor(15);
if(key!=13)
break;
}
while(1);
return 0;
}
{
int x1=x_1;
int y1=y_1;
int x2=x_2;
int y2=y_2;
if(x_1>x_2)
{
x1=x_2;
y1=y_2;
x2=x_1;
y2=y_1;
}
int dx=abs(x2-x1);
int dy=abs(y2-y1);
int two_dx=(2*dx);
int two_dx_dy=(2*(dx-dy));
int p=((2*dx)-dy);
int x=x1;
int y=y1;
while(y<y2)
{
y++;
if(p<0)
p+=two_dx;
else
{
x++;
p+=two_dx_dy;
}
}
}
void show_screen( )
{
restorecrtmode( );
textmode(C4350);
cprintf("\n*********************************************************************
***********");
cprintf("*************************- -***********************");
cprintf("*------------------------- ");
textbackground(1);
textbackground(8);
cprintf(" -----------------------*");
cprintf("*-***********************- -*********************-*");
cprintf("*-************************************************************-*");
cprintf("*-* *-*");
gotoxy(1,46);
cprintf("*-*************************************************************-*");
cprintf("*------------------------------------------------------------------------------*");
cprintf("******************************************************************");
gotoxy(8,40);
cout<<"Note :";
gotoxy(8,41);
gotoxy(12,43);
cout<<"The slope of the line should be negative and greater than 1.";
gotoxy(1,2);
}
A C++ program to draw a line using Digital Differential Analyzer (DDA) Algorithm.
# include <conio.h>
# include <math.h>
void dda_line(const int,const int,const int,const int);
int main( )
{
int driver=VGA;
int mode=VGAHI;
int x_1=0;
int y_1=0;
int x_2=0;
int y_2=0;
do
{
show_screen( );
gotoxy(8,10);
gotoxy(8,11);
gotoxy(12,13);
cin>>x_1;
gotoxy(12,14);
cin>>y_1;
gotoxy(8,18);
gotoxy(8,19);
gotoxy(12,21);
cin>>x_2;
gotoxy(12,22);
cin>>y_2;
setcolor(15);
dda_line(x_1,y_1,x_2,y_2);
setcolor(15);
if(key!=13)
break;
}
while(1);
return 0;
}
void dda_line(const int x_1,const int y_1,const int x_2,const int y_2)
{
int x1=x_1;
int y1=y_1;
int x2=x_2;
int y2=y_2;
if(x_1>x_2)
{
x1=x_2;
y1=y_2;
x2=x_1;
y2=y_1;
}
float dx=(x2-x1);
float dy=(y2-y1);
int steps=abs(dy);
if(abs(dx)>abs(dy))
steps=abs(dx);
float x_inc=(dx/(float)steps);
float y_inc=(dy/(float)steps);
float x=x1;
float y=y1;
for(int count=1;count<=steps;count++)
{
x+=x_inc;
y+=y_inc;
putpixel((int)(x+0.5),(int)(y+0.5),color);
}
}
void show_screen( )
{
restorecrtmode( );
textmode(C4350);
cprintf("\n*****************************************************************");
cprintf("******************- -*****************");
cprintf("*------------------ ");
textbackground(1);
cprintf(" Digital Differential Analyzer Algorithm ");
textbackground(8);
cprintf(" -----------------*");
cprintf("*-****************- -***************-*");
cprintf("*-*********************************************************-*");
cprintf("*-* *-*");
gotoxy(1,46);
cprintf("*-***********************************************************-*");
cprintf("*------------------------------------------------------------------------------*");
cprintf("************************************************************");
gotoxy(1,2);
}
lines with slopes positive and less than 1.
# include <conio.h>
# include <math.h>
int main( )
{
int driver=VGA;
int mode=VGAHI;\
int x_1=0;
int y_1=0;
int x_2=0;
int y_2=0;
do
{
show_screen( );
gotoxy(8,10);
gotoxy(8,11);
gotoxy(12,13);
cin>>x_1;
gotoxy(12,14);
cin>>y_1;
gotoxy(8,18);
gotoxy(8,19);
gotoxy(12,21);
cin>>x_2;
gotoxy(12,22);
cin>>y_2;
setcolor(15);
setcolor(15);
if(key!=13)
break;
}
while(1);
return 0;
}
{
int x1=x_1;
int y1=y_1;
int x2=x_2;
int y2=y_2;
if(x_1>x_2)
{
x1=x_2;
y1=y_2;
x2=x_1;
y2=y_1;
}
int dx=abs(x2-x1);
int dy=abs(y2-y1);
int two_dy=(2*dy);
int p=((2*dy)-dx);
int x=x1;
int y=y1;
while(x<x2)
{
x++;
if(p<0)
p+=two_dy;
else
{
y--;
p+=two_dy_dx;
}
}
}
void show_screen( )
{
restorecrtmode( );
textmode(C4350);
cprintf("\n************************************************************");
cprintf("*************************- -***********************");
cprintf("*------------------------- ");
textbackground(1);
textbackground(8);
cprintf(" -----------------------*");
cprintf("*-***********************- -*********************-*");
cprintf("*-*******************************************************-*");
cprintf("*-* *-*");
gotoxy(1,46);
cprintf("*-*********************************************************-*");
cprintf("*------------------------------------------------------------------------------*");
cprintf("***************************************************************");
gotoxy(8,40);
cout<<"Note :";
gotoxy(8,41);
gotoxy(12,43);
cout<<"The slope of the line should be positive and less than 1.";
gotoxy(1,2);
}
A C++ program to draw a circle using Bresenham's Circle Algorithm.

# include <conio.h>
# include <math.h>
void bresenham_circle(const int,const int,const int);
int main( )
{
int driver=VGA;
int mode=VGAHI;
int h=0;
int k=0;
int r=0;
do
{
show_screen( );
gotoxy(8,10);
cout<<"Central Point of the Circle : (h,k) :";
gotoxy(8,11);
cout<<"ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ";
gotoxy(12,13);
cout<<"Enter the value of h = ";
cin>>h;
gotoxy(12,14);
cout<<"Enter the value of k = ";
cin>>k;
gotoxy(8,18);
cout<<"Radius of the Circle : r :";
gotoxy(8,19);
cout<<"ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ";
gotoxy(12,21);
cout<<"Enter the value of r = ";
cin>>r;
setcolor(15);
bresenham_circle(h,k,r);
setcolor(15);
if(key!=13)
break;
}
while(1);
return 0;
}
void bresenham_circle(const int h,const int k,const int r)
{
int x=0;
int y=r;
int p=(3-(2*r));
do
{
putpixel((h+x),(k+y),color);
putpixel((h+y),(k+x),color);
putpixel((h+y),(k-x),color);
putpixel((h+x),(k-y),color);
putpixel((h-x),(k-y),color);
putpixel((h-y),(k-x),color);
putpixel((h-y),(k+x),color);
putpixel((h-x),(k+y),color);
x++;
if(p<0)
p+=((4*x)+6);
else
{
y--;
p+=((4*(x-y))+10);
}
}
while(x<=y);
}
void show_screen( )
{
restorecrtmode( );
textmode(C4350);
cprintf("\n***************************************************************");
cprintf("***********************- -***********************");
cprintf("*----------------------- ");
textbackground(1);
cprintf(" Bresenham's Circle Algorithm ");
textbackground(8);
cprintf(" -----------------------*");
cprintf("***********************- -***********************");
cprintf("*-***********************************************************-*");
cprintf("*-* *-*");
gotoxy(1,46); gotoxy(1,2); }
A C++ program to draw a circle using MidPoint Circle Algorithm.
# include <conio.h>
# include <math.h>
void midpoint_circle(const int,const int,const int);
int main( )
{
int driver=VGA;
int mode=VGAHI;
int h=0;
int k=0;
int r=0;
do
{
show_screen( );
gotoxy(8,10);
cout<<"Central Point of the Circle : (h,k) :";
gotoxy(8,11);
cout<<"ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ";
gotoxy(12,13);
cout<<"Enter the value of h = ";
cin>>h;
gotoxy(12,14);
cout<<"Enter the value of k = ";
cin>>k;
gotoxy(8,18);
cout<<"Radius of the Circle : r :";
gotoxy(8,19);
cout<<"ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ";
gotoxy(12,21);
cout<<"Enter the value of r = ";
cin>>r;
setcolor(15);
midpoint_circle(h,k,r);
setcolor(15);
if(key!=13)
break;
}
while(1);
return 0;
}
void midpoint_circle(const int h,const int k,const int r)
{
int x=0;
int y=r;
int p=(1-r);
do
{
x++;
if(p<0)
p+=((2*x)+1);
else
{
y--;
p+=((2*(x-y))+1);
}
}
while(x<=y);
}
void show_screen( )
{
restorecrtmode( );
textmode(C4350);
cprintf("\n****************************************************************");
cprintf("*-***********************- -**********************-*");
cprintf("*------------------------- ");
textbackground(1);
cprintf(" MidPoint Circle Algorithm ");
textbackground(8);
cprintf(" ------------------------*");
cprintf("*-**************************************************************-*");
cprintf("*-* *-*");
gotoxy(1,46);
cprintf("***************************************************************");
gotoxy(1,2); }
A C++ program to fill different types of geometric shapes using Boundary
# include <conio.h>
# include <math.h>
void BoundaryFill(const int,const int,const int,const int);
void Circle(const int,const int,const int);
void Triangle(const int,const int,const int,const int,const int,const int);
void Rectangle(const int,const int,const int,const int);
void Polygon(const int,const int []);
void Line(const int,const int,const int,const int);
int main( )
{
int driver=VGA;
int mode=VGAHI;
show_screen( );
setcolor(15);
Circle(175,175,50);
BoundaryFill(175,175,10,15);
setcolor(15);
settextstyle(0,0,1);
outtextxy(150,235,"Circle");
setcolor(15);
Rectangle(350,135,500,225);
setcolor(15);
outtextxy(390,235,"Rectangle");
setcolor(15);
Triangle(125,370,225,370,175,280);
setcolor(15);
outtextxy(145,380,"Triangle");
int polygon_points[14]={ 340,330, 390,285, 460,285, 510,330,
460,375, 390,375, 340,330 };
setcolor(15);
Polygon(7,polygon_points);
setcolor(15);
outtextxy(397,380,"Polygon");
getch( );
return 0;
}
struct Pixel
{
int x;
int y;
Pixel *Next;
};
Pixel *Entry=NULL;
Pixel *Start=NULL;
Pixel *Last=NULL;
void insert_pixel(const int x,const int y)
{
Entry=new Pixel;
Entry->x=x;
Entry->y=y;
Entry->Next=NULL;
Last->Next=Entry;
Last=Entry;
}
void BoundaryFill(const int _x,const int _y,
const int fill_color,const int boundary_color)
{
if(getpixel(_x,_y)==boundary_color || getpixel(_x,_y)==fill_color)
return;
int x=_x;
int y=_y;
Start=new Pixel;
Start->x=x;
Start->y=y;
Start->Next=NULL;
Last=Start;
while(Start!=NULL)
{
putpixel(x,y,fill_color);
if(getpixel((x-1),y)!=boundary_color &&
getpixel((x-1),y)!=fill_color&& (x-1)>=0)
{
putpixel((x-1),y,fill_color);
insert_pixel((x-1),y);
}
if(getpixel(x,(y-1))!=boundary_color &&
getpixel(x,(y-1))!=fill_color&& (y-1)>=0)
{
putpixel(x,(y-1),fill_color);
insert_pixel(x,(y-1));
}
if(getpixel((x+1),y)!=boundary_color &&
getpixel((x+1),y)!=fill_color&& (x+1)<=getmaxx( ))
{
putpixel((x+1),y,fill_color);
insert_pixel((x+1),y);
}
if(getpixel(x,(y+1))!=boundary_color &&
getpixel(x,(y+1))!=fill_color&& (y-1)<=getmaxy( ))
{
putpixel(x,(y+1),fill_color);
insert_pixel(x,(y+1));
}
Entry=Start;
Start=Start->Next;
x=Start->x;
y=Start->y;
delete Entry;
}
}
void Circle(const int h,const int k,const int r)
{
int x=0;
int y=r;
int p=(1-r);
do
{
x++;
if(p<0)
p+=((2*x)+1);
else
{
y--;
p+=((2*(x-y))+1);
}
}
while(x<=y);
}
void Triangle(const int x_1,const int y_1,const int x_2,const int y_2,
const int x_3,const int y_3)
{
Line(x_1,y_1,x_2,y_2);
Line(x_2,y_2,x_3,y_3);
Line(x_3,y_3,x_1,y_1);
}
void Rectangle(const int x_1,const int y_1,const int x_2,const int y_2)
{
Line(x_1,y_1,x_2,y_1);
Line(x_2,y_1,x_2,y_2);
Line(x_2,y_2,x_1,y_2);
Line(x_1,y_2,x_1,y_1);
}
void Polygon(const int n,const int coordinates[])
{
if(n>=2)
{
Line(coordinates[0],coordinates[1],
coordinates[2],coordinates[3]);
for(int count=1;count<(n-1);count++)
Line(coordinates[(count*2)],coordinates[((count*2)+1)],
coordinates[((count+1)*2)],
coordinates[(((count+1)*2)+1)]);
}
}
void Line(const int x_1,const int y_1,const int x_2,const int y_2)
{
int x1=x_1;
int y1=y_1;
int x2=x_2;
int y2=y_2;
if(x_1>x_2)
{
x1=x_2;
y1=y_2;
x2=x_1;
y2=y_1;
}
int dx=abs(x2-x1);
int dy=abs(y2-y1);
int inc_dec=((y2>=y1)?1:-1);
if(dx>dy)
{
int two_dy=(2*dy);
int p=((2*dy)-dx);
int x=x1;
int y=y1;
while(x<x2)
{
x++;
if(p<0)
p+=two_dy;
else
{
y+=inc_dec;
p+=two_dy_dx;
}
}
}
else
{
int two_dx=(2*dx);
int two_dx_dy=(2*(dx-dy));
int p=((2*dx)-dy);
int x=x1;
int y=y1;
while(y!=y2)
{
y+=inc_dec;
if(p<0)
p+=two_dx;
else
{
x++;
p+=two_dx_dy;
}
}
}
}
void show_screen( )
{
setfillstyle(1,1);
bar(220,26,420,38);
setcolor(15);
outtextxy(5,5,"********************************************************");
outtextxy(5,17,"*-***********************************************-*");
outtextxy(5,29,"*------------------------- ------------------------*");
outtextxy(5,41,"*-************************************************-*");
outtextxy(5,53,"*-*********************************************-*");
setcolor(11);
outtextxy(228,29,"Boundary Fill Algorithm");
setcolor(15);
for(int count=0;count<=30;count++)
outtextxy(5,(65+(count*12)),"*-* *-*");
outtextxy(5,438,"*-********************************************-*");
outtextxy(5,450,"*------------------------- -------------------------*");
outtextxy(5,462,"**********************************************");
setcolor(12);
outtextxy(229,450,"Press any Key to exit.");
}
PROGRAM TO ROTATE A TRIANGLE ABOUT ORIGIN.

#include<iostream.h>
#include<conio.h>
#include<graphics.h>
#include<process.h>
#include<math.h>
void main()
{
clrscr();
int graphdriver=DETECT,graphmode;
initgraph(&graphdriver,&graphmode,"...\\bgi");
int x,y,x1,a[3][3];
double b[3][3],c[3][3];
printf"\n Enter Ist coordinates of triangle:";
scanf(―%d%d‖,&a[0][0],&a[1][0]);
printf"\n Enter 2nd coordinates of triangle:";

scanf(―%d%d‖,&a[0][1],&a[1][1]);
printf"\n Enter 3rd coordinates of triangle:";

scanf(―%d%d‖,&a[0][2],&a[1][2]);
line(a[0][0],a[1][0],a[0][1],a[1][1]);
line(a[0][1],a[1][1],a[0][2],a[1][2]);
line(a[0][0],a[1][0],a[0][2],a[1][2]);
getch();
cleardevice();
printf"\n Enter angle of rotation:\n";
scanf(―%d‖,&x);
b[0][0]=b[1][1]=cos((x*3.14)/180);
b[0][1]=-sin((x*3.14)/180);
b[1][0]=sin((x*3.14)/180);
b[2][2]=1;
b[2][0]=b[2][1]=b[0][2]=b[1][2]= 0;
for(int i=0;i<3;i++)
{
for(int j=0;j<3;j++)
{ c[i][j]=0;
for (int k=0; k<3;k++)
{
c[i][j]+=a[i][k]*b[k][j];
}
x1=(c[i][j]+0.5);
a[i][j]=x1;
}
}
printf"\n Triangle after rotation is:\n" ;
line(a[0][0],a[1][0],a[0][1],a[1][1]);
line(a[0][1],a[1][1],a[0][2],a[1][2]);
line(a[0][0],a[1][0],a[0][2],a[1][2]);
getch();
closegraph();
}
PROGRAM TO SCALE THE TRIANGLE
#include<conio.h>
#include<graphics.h>O
void main()
{
int gd=DETECT,gm;
initgraph(&gd, &gm,"");
cleardevice();
int x1,y1,x2,y2,x3,y3,x4,y4;
float sx,sy;
printf"Enter the first coordinates of triangle\n";
scanf(―%d%d‖,&x1,&y1);
printf"Enter the second coordinates of triangle\n";
printf"Enter the third coordinates of triangle\n";
int poly[8]={x1,y1,x2,y2,x3,y3,x1,y1};
cleardevice();
drawpoly(4,poly);
getch();
printf"Enter the scaling factors\n";
scanf(―%d%d‖,&sx,&sy);
x4=sx*x1-x1;
y4=sy*y1-y1;
x1=sx*x1-x4;
y1=sy*y1-y4;
x2=sx*x2-x4;
y2=sy*y2-y4;
x3=sx*x3-x4;
y3=sy*y3-y4;
poly[0]=x1;
poly[1]=y1;
poly[2]=x2;
poly[3]=y2;
poly[4]=x3;
poly[5]=y3;
poly[6]=x1;
poly[7]=y1;
getch();
cleardevice();
drawpoly(4,poly);
getch();
closegraph();
}
PROGRAM TO TRANSLATE A TRIANGLE
#include<conio.h>
#include<process.h>
#include<math.h>
void main()
{
clrscr();
int x,y,x1,y1,x2,y2,x3,y3;


cleardevice();
line(x1,y1,x2,y2);
line(x2,y2,x3,y3);
line(x1,y1,x3,y3);
getch();
cleardevice();
printf"\n Enter translatio factors :\n";

scanf(―%d%d‖,&x,&y);
x1-=x;
y1-=y;
x2-=x;
y2-=y;
x3-=x;
y3-=y;
cleardevice();
line(x1,y1,x2,y2);
line(x2,y2,x3,y3);
line(x1,y1,x3,y3);
getch();
closegraph();
}
PROGRAM TO ROTATE A POINT ABOUT A POINT
#include<conio.h>
#include<math.h>
#include<dos.h>
void main()
{
clrscr();
int gm,gd=DETECT;
initgraph(&gd,&gm,"");
int h,k,x1,y1,x2,y2,x3,y3;
float t;
printf" OUTPUT");
printf"Enter the coordinates of point");
putpixel(x2,y2,2);
printf"Enter the coordinates of point around which rotation is done");

scanf(―%d%d‖,&h,&k);
putpixel(h,k,2);
printf"Enter the angle for rotation");

scanf(―%d‖,&t);
cleardevice();
x1=(h*cos(t))-(k*sin(t));
y1=(h*sin(t))+(k*cos(t));
x3=x1+x2-h;
y3=y1+y2-k;
printf"Point after rotation is:";

putpixel(x3,y3,2);
getch();
closegraph();
}
PROGRAM TO ROTATE A POINT ABOUT ORIGIN
#include<conio.h>
#include<math.h>
#include<dos.h>
void main()
{
clrscr();
int gm,gd=DETECT;
initgraph(&gd,&gm,"");
int h,k,x1,y1,x2,y2,x3,y3;
float t;
printf" OUTPUT");
printf"Enter the coordinates of point");
putpixel(x2,y2,2);
printf"Enter the angle for rotation");

scanf(―%d‖,&t);
cleardevice();
x1=int(x2*cos(t*3.14/180))-(y2*sin(t*3.14/180));
y1=int(x2*sin(t*3.14/180))+(y2*cos(t*3.14/180));
printf"Point after rotation is:";
putpixel(x1,y1,2);
getch();
closegraph();
PROGRAM TO REFLECT A TRIANGLE
#include<conio.h>
#include<process.h>
#include<math.h>
void main()
{
clrscr();
int x,y,x1,a[3][3];
double b[3][3],c[3][3];
scanf(―%d%d‖,&a[0][0],&a[1][0]);
scanf(―%d%d‖,&a[0][1],&a[1][1]);

scanf(―%d%d‖,&a[0][2],&a[1][2]);
printf"\n Enter 1. for reflection in x-axis:\n";

printf"\n Enter 2. for reflection in y-axis:\n";
printf"\n Enter 3. for reflection in both the axis:\n";
scanf(―%d‖,&x);
cleardevice();
line(320,0,320,479);
line(0,240,639,240);
line(a[0][0],a[1][0],a[0][1],a[1][1]);
line(a[0][1],a[1][1],a[0][2],a[1][2]);
line(a[0][0],a[1][0],a[0][2],a[1][2]);
switch(x)
{
case 1:b[0][0]=640-a[0][0];
b[0][1]=640-a[0][1];
b[0][2]=640-a[0][2];
b[1][0]=a[1][0];
b[1][1]=a[1][1];
b[1][2]=a[1][2];
line(320,0,320,479);
line(0,240,639,240);
line(b[0][0],b[1][0],b[0][1],b[1][1]);
line(b[0][1],b[1][1],b[0][2],b[1][2]);
line(b[0][0],b[1][0],b[0][2],b[1][2]);
getch();
break;
case 2:b[1][0]=480-a[1][0];
b[1][1]=480-a[1][1];
b[1][2]=480-a[1][2];
b[0][0]=a[0][0];
b[0][1]=a[0][1];
b[0][2]=a[0][2];
line(320,0,320,479);
line(0,240,639,240);
line(b[0][0],b[1][0],b[0][1],b[1][1]);
line(b[0][1],b[1][1],b[0][2],b[1][2]);
line(b[0][0],b[1][0],b[0][2],b[1][2]);
getch();
break;
case 3: b[0][0]=640-a[0][0];
b[0][1]=640-a[0][1];
b[0][2]=640-a[0][2];
b[1][0]=a[1][0];
b[1][1]=a[1][1];
b[1][2]=a[1][2];
line(320,0,320,479);
line(0,240,639,240);
line(b[0][0],b[1][0],b[0][1],b[1][1]);
line(b[0][1],b[1][1],b[0][2],b[1][2]);
line(b[0][0],b[1][0],b[0][2],b[1][2]);
b[1][0]=480-a[1][0];
b[1][1]=480-a[1][1];
b[1][2]=480-a[1][2];
b[0][0]=a[0][0];
b[0][1]=a[0][1];
b[0][2]=a[0][2];
line(320,0,320,479);
line(0,240,639,240);
line(b[0][0],b[1][0],b[0][1],b[1][1]);
line(b[0][1],b[1][1],b[0][2],b[1][2]);
line(b[0][0],b[1][0],b[0][2],b[1][2]);
getch();
break;
}
getch();
closegraph();
MULTIMEDIA
Moving from 2D to 3D design can be challenging since most of us design using only two
dimensions. However, you‘ve done this before but you just don‘t remember! Maybe you haven‘t
realized that building objects in Maya 3D is somehow similar to building objects using Legos.
The key to design in Maya 3D is to think spatially. In Maya, we design not only acknowledging
width and height we also incorporate depth!
It takes some practice and lots of patience to develop 3D spatial ability, so below you‘ll find
some basic Maya 101 concepts that will help you better understand the 3D environment.
1. X,Y and Z
In Maya the X axis is the width (red), the y axis is the height (green) and the Z axis is the depth
(blue). The y-axis is also referred to as Y-up. The center of the coordinate system is called the
origin and the coordinates are 0, 0, 0 for x, y, z.
If you want to manipulate an object in Maya you can:

a) Enter x, y and z values for translate, rotate and scale in ―Channel Box‖
 Translate: Value ―0‖ in x, y and z, position the object on the center or ―origin‖ of the
workspace.
 Rotate: If you by mistake rotate an object, set all the values to ―0‖. This will take the
object back to its default position.
 Scale: ―1‖ is the default value and it means the object‘s size is 100%. If you want to make
the object twice its size enter 2 in all the scale values.If you want to make an object half
its size enter 0.5 in all the scale values
b) Use the manipulators handles of the move tool, scale tool and rotate tool.
When moving & rotating objects in Maya, it‘s recommended that you move or rotate the object
only along one axis, this can help you maintain your objects aligned.
You can do this by pulling the arrows of the move tool or by dragging the rings of the rotate tool.
Moving the objects from the center handle will allow you to move the object freely across the
view plane and it can be hard to control its translation and rotation.
When scaling object is Maya, if you want to maintain the object‘s proportions drag the center
box to scale uniformly in all directions.
2. Views
When working in a 3D environment is very important to check that the object you are building
looks good in all the views. Looking to just one view can be deceiving and you object might not
be positioned correctly.
In order to ease the design process Maya provides up to 4 views, one perspective view and three
orthographic views.
When you look at the object from the perspective view you can revolve the camera to freely
tumble around the object. However, when you use orthographic views (top, side & front) they
only focus in 2 axes at the time, so you can‘t tumble around (unless you use the tumble tool).
3. Polygonal Modeling vs NURBS Modeling

Polygons:
Polygons are the most basic geometry in Maya they are straight-sided shapes of 3 sides or more.
Polygons have faces, edges & vertices, some examples of polygons or primitive shapes are
spheres, cubes, cylinders, cones, and planes.
Because polygon‘s surfaces can be directly extruded, scaled and positioned designers prefer
them to create characters in Maya.
NURBS Curves and NURBS Surfaces:
NURBS curves stand for Non-Uniform Rational B-Splines. NURBS curves are very handy since
you can draw them in Maya or import them from a vector program like Adobe Illustrator.
NURBS primitives or surfaces, use UV coordinate space and you can modify them by trimming
away portions of their forms, beveling their edges, or by sculpting them into different shapes
using the Maya Artisan sculpting
tools
NURBS are preferred for constructing organic 3D forms because of their smooth & natural
characteristics.
4. Pivot
All transformations to an object are relative to the pivot point. The object‘s pivot affects scale
since the object will scale out from or in toward the pivot point. The pivot also affects the
object‘s rotation/animation because an object rotates around the pivot point.
5. Subdivisions
Polygon Subdivisions:
If a polygon has less subdivisions, for example an value of ―5‖, it will have less detail and a
rougher surface
If a polygon has more subdivisions, for example an value of ―20‖, it will have more detail & a
smoother surface
NURBS Subdivisions
If a NURB has less sections & spans, for example an value of ―2‖, it will have less detail and a
rougher surface
If a NURB has more sections & spans, for example an value of ―20‖, it will have more detail & a
smoother surface
6. UV Coordinate Space:
Surfaces in Maya have their own coordinate space. UV Coordinate Space is useful when
working with curve-on-surfaces and positioning textures.
7. Nodes
Every element in Maya is built with a single or a series of nodes. Nodes define all attributes like
lighting, shading and geometry.
For example a primitive polygon, such as a sphere, is built from several nodes: a creation node
that records the options that created the sphere, a transform node that records how the object is
moved, rotated, and scaled, and a shape node that stores the positions of the spheres control
points.
Shape nodes:
Holds an object‘s geometry attributes or attributes other than the object‘s transform node
attributes.
Rendering nodes:
Materials and textures each have nodes containing attributes that control their look. Texture
placement nodes have attributes that control how a texture is fitted onto a surface.
8. Attributes:
An attribute is a position associated with a node that can hold a value or a connection to another
node. Attributes control how a node works.
To change an object‘s attributes you can use the Attribute Editor & the Channel Box.
9. Construction History:
When you work in Maya, all the actions you make create nodes in the construction history of the
objects you are working on. Construction history is very important because it allows you to
change an object.
If you are only modeling it‘s recommended that you delete construction history once you are
100% sure you have the object you need. This prevents accidental changes and speeds up the
shading & rendering process. However, if you are going to animate is not recommended that you
don‘t delete construction history since some dependency nodes have attributes that can be
animated.
10. Hierarchy
Grouping
To control multiple objects with one node, you can group objects together under a new transform
node. By grouping objects, you can move, shade, texture, and do many other actions to all the
objects at the same time.
Parenting
The child objects have independent nodes, for example a child can rotate by itself without
rotating the parent. However, if the parent is rotated or moved the child follows.
Object Manipulation Tools
Maya's tool selection icons on the left side of the user interface.
So now you know how to place an object in your scene and modify some of its basic attributes.
Let's explore some of the ways we can change its position in space. There are three basic forms
of object manipulation in any 3D application—translate (or move), scale, and rotate.
Obviously, these are all operations that sound relatively self-explanatory, but let's take a look at
some of the technical considerations.
There are two different ways to bring up the translate, scale, and rotate tools:
First, they can be accessed from the toolbox panel (pictured above) on the left side of your view-
port.
The second (preferred method) is to use keyboard hotkeys. During the modeling process, you'll
be switching between tools constantly, so it's a good idea to learn the commands as quickly as
possible.
With an object selected, use the following hotkeys to access Maya's translate, rotate, and scale
tools:
Translate - w.
Rotate - e.
Scale - r.
To exit any tool, hit q to return to selection mode.
Translate (Move)
Select the object you created and strike the w key to bring up the translation tool.
When you access the tool, a control handle will appear at your object's central pivot point, with
three arrows aimed along the X, Y, and Z axes.
To move your object away from the origin, click any one of the arrows and drag the object along
that axis. Clicking anywhere on the arrow or shaft will constrain movement to the axis it
represents, so if you only want to move your object vertically, simply click anywhere on the
vertical arrow and your object will be constrained to vertical movement.
If you'd like to translate the object without constraining motion to a single axis, clicking in the
yellow square at the center of the tool to allow free translation. When moving an object on
multiple axes, it's often beneficial to switch into one of your orthographic cameras (by
clicking spacebar, in case you'd forgotten) for more control.
Scale
The scale tool functions almost exactly like the translate tool.
To scale along any axis, simply click and drag the (red, blue, or green) box that corresponds to
the axis you'd like to manipulate.
To scale the object globally (simultaneously on all axes), click and drag the box located at the
center of the tool. Simple as that!
Rotate
As you can see, the rotation tool appears and operates slightly different from the translate and
scale tools.
Like translate and scale, you can constrain rotation to a single axis by clicking and dragging any
of the three inner rings (red, green, blue) visible on the tool.
You can freely rotate the object along multiple axes, by simply clicking and dragging in the gaps
between rings, however you're afforded a lot more control by rotating an object one axis at a
time.
Finally, by clicking and dragging on the outer ring (yellow), you can rotate an object
perpendicular to the camera.
With rotation, there are times when a bit more control is necessary—on the next page we'll look
at how we can use the channel box for precise object manipulation.
In animation, there's more to animate than simple movement. Animation requires thinking about
motion, timing, and smoothness of action. Almost anything in Maya with a number attached to it
can be animated. Maya simplifies your work in creating the essence of animation---timing and
motion. With maya , you can animate virtually anything you can imagine, no matter how
surreal. When you set a keyframe (or key), you assign a value to an object‘s attribute (for
example, translate, rotate, scale, color, etc.) at a specific time.
ANIMATION
Most animation systems use the frame as the basic unit of measurement because each frame is
played back in rapid succession to provide the illusion of motion.
The frame rate (frames per second) that is used to play back an animation is based on the
medium that the animation will be played back (for example, film, TV, video game, etc.)
When you set several keys at different times with different values, Maya generates the attribute
values between those times as the scene plays back each frame. The
Animation Control and Interface
With Maya's animation controls, you choose how to key and play an animation. Two
components of Maya's user interface are specific to animation: the Range Slider and the Time
Slider. You can also quickly access and edit animation preferences from the animation controls
area.
Fig 1 Animation controls

Between the Range slider and the Animation Preferences button are the current character control
features and the Auto Key button.
Time Slider
The Time Slider is a vital part of the animation interface in Maya. The Time Slider Controls the
Playback range, keys and breakdowns with in the playback range.
Fig 2 Time slider

Click in the Time Slider area and drag left and right to "scrub" the animation back and forward in
time.
Key Ticks
Key Ticks are red marks in the Time Slider where you set a key for the selected object.
Breakdowns are a special type of key .The visibility of Key Ticks can be turned off or on in the
Preference window. The current Time indicator is a gray block on the Time Slider. You can drag
it to move forward and backward in your animation.
Current Time Field
A black line indicates the current time field. When keys have been set for the currently selected
object, thin vertical red lines appear in the Time Slider area to indicate the times for those keys.
Range Slider
The Range Slider controls the playback range reflected in the Time Slider. The Range Slider sets
the total length of the animation in frames. You can also use the Range Slider to temporarily
limit the range of playback and set the playback start and end frames.
Fig 3 Range slider
 You can toggle whether the Range Slider is Displayed or hidden by selecting Display>UI
elements>Range Slider.
 Animation Start Time sets the start time of the animation.
 Animation End Time sets the end time of the animation.
 Playback Start Time This shows the current start time for the playback range. You can
change it by entering a new start time.
 Playback End Time This shows the current end time for the playback range. You can
change it by entering a new end frame.
 Range Slider Bar This lets you control the playback range of your animation up to the
limits of the Animation start/end settings.
You use the Preferences dialog box to change values for the animation timeline and playback.
You can also set the total time for your animation, the size of the timeline, and other related
features.
Fig 4 Preferences dialog box
Terms in Animation
Frame Rate
Frame rate is the first aspect of animation. By default, Maya sets your animation to Film, which
plays at 24fps.You use 30fps in the United States and 25fps in other countries.
Range
The range of an animation determines the total length in frames. Then, multiply the animation's
length in seconds by the frame rate .For e.g in this case you are using 24fps and animation length
is of 2seconds.
24fps X 2secs =48 Frames
Setting Keys
You can set a Key by selecting Animate >Set Key. The attributes set by this menu item depend
on the set Key option settings.
Animation Types
There are following types to animate your scene.
Path Animation
In this method, you create a NURBS-based curve and then attach an object to it in your scene.
The object then follows the curved path to simulate motion. You can choose at which time the
object is positioned at any point along the path, so the object can reverse itself, pause, or
oscillate, if you want. The object automatically rotates from side to side as the curve changes
directions. If the object is geometry, it can also be automatically deformed to follow the contours
of the curve.
Select Animate>Motion paths>Attach to Motion path
To Animate an object along a surface
 Choose create >Nurbs Primitives > Plane to create a Nurbs plane.
 Select Modify>Transformation Tools>Proportional Modification Tool to introduce

contours on the plane.
 Select Modify > Make Live ,then draw a curve on the plane.
 Create an object to animate along the path , and shift -click on the curve on surface to
select it.
 Select Animate>Motion Paths >Attach to Motion Path option window. Ensure that
follow is on ,and set the up direction to normal so that the object will stay normal to the
surface.
 Click play to see your animation.
Flow Path Object Function
The Flow Path Object function creates a lattice around an object .
Select Animate>Motion paths>Flow Path Object
Keyframe Animation
Keyframe animation is the standard animation method. In this method, you set keys for an
object's extreme positions and let the computer fill in the in-between motion. A key is an anchor
point for a particular attribute at a designated time. When the animation reaches that specified
time, the object's attribute will be at the value you set. As you set keys, you specify the time at
which those changes in the attribute's value take place.
To set keys with the auto keyframe method, you click the Auto Keyframe button in the Range
Slider (it turns red to indicate that it's enabled). With auto keyframing, you can animate quickly
by simply dragging the Time Slider to a given frame and then changing an attribute.
Nonlinear Animation
Nonlinear animation is a more advanced method of animation. Unlike keyframing, nonlinear
animation is completely independent of time. You blend and layer animation sequences—called
clips—to set up the motion for objects. You can also use this method to explore variations in
parts of the animation without losing your previous work or affecting other parts of the
animation. For example-you can make the walking part of the animation a clip and then adjust
the leg motion without affecting the way the rest of the character moves.
Graph Editor
The Graph Editor is a helpful tool for tweaking values for keys you have set. It gives you a visual
representation—a curved line—of the attributes that are animated. The animation time goes from
left to right, and any keyed variable appears as a line that ramps up or down to indicate its value
over time. It can help you visualize how things are changing and how fast. You can pan and
zoom this panel like any other.
Fig 5 Graph Editor
To use it as a free-floating window, simply open it from the Hotbox (Window >Animation
Editors> Graph Editor).
Graph Editor's Components
Menu bar
The Graph Editor menu bar contains tools and operations for manipulating animation curves and
keys with in the graph view of the Graph editor. The Edit menu is similar to the one in text
editors or word processors, except that you're working with keys instead of text.
Fig 6 Menu Bar
The Edit Menu

The menu items appear under Edit menu behave in a similar fashion to the main Edit menu in the
modeling view.
The View Menu

This menu controls which components are visible, and therefore editable, in the graph view of
the Graph Editor.
The Select Menu

These options control which component of an animation curve are available for selection and
editing.
The Curves Menu

The Curves menu gives you control over how the curves are set up with the keys in your scene.
The Keys menu

This menu includes Tangents which causes the manipulation of an in or out tangent handle.
The Tangents Menu
This describes the entry and exit of curve segments from a key.
The List Menu

This menu Loads the objects.
Toolbar
The toolbar gives you quick access to functions for modifying animation curves and keys.
Fig 7 Toolbar
 Buffer curves Use Buffer Curve snapshot and swap Buffer curves to compare changes to
the current animation curve with its previous shape.
 Break Tangents Allows manipulation of the in and out tangent handles individually so
you can edit the curve segment entering the key without affecting its opposite handle.
 Unify Tangents causes the manipulation of an in or out tangent handle to affect its
opposite handle equally. It retains the relative position of the tangent handles even after
tangents are individually adjusted.
 Lock Tangent Weight specifies that when you move a tangent ,only its angle can be
changed.
 Free Tangent Weight specifies that when you move a tangent ,only its angle can be
changed. This allows the weight of a tangent to be adjusted as well as the angle.
 Clamped tangent creates an animation curve that has the characteristics of linear and
spline curves. The key's tangents will be spline unless the value of two adjacent keys are
very close.
 Step tangent creates an animation curve whose out tangent is a flat curve.
 Flat Sets the in and out tangents of the key to be horizontal.
The Dope Sheet
The Dope Sheet is another animation editor in Maya that is similar to the Graph Editor. Instead
of displaying curves, the Dope Sheet displays key times as colored rectangles and lets you edit
event timing in blocks of keyframes and synchronize motion to a sound file.
To open the Dope Sheet

Select Window > Animation Editors > Dope Sheet
Fig 8 Dope sheet editor
To Place the Dope Sheet in a View

Select the view.
Select Panels > Panel > Dope Sheet.
EXPERIMENTS
Experiment-1
AIM:-To create a wine glass using EP curve tool.
STEPS:-
Step 1: Select ‗Modeling‘ from main menu bar.
Step 2: Select ‗EP curve tool‘ from ‗Curves‘.
Step 3: Click each coordinate in plane to fix the points forming the curve in the shape of half
wine glass.
Step 4: Press 5 to solidify and click ‗Surfaces‘ from Maya title bar and select ‗Revolve‘ to obtain
complete wine glass.
OUTPUT
Single Perspective View
Four View
Experiment-2
AIM:-To create a building with balcony and a door at the base of the building using polygon and
NURBS primitives.
STEPS:-
Step 1: Select ‗Modeling‘ from main menu bar.

Step 2: Create the building by clicking on ‗Polygon‘s primitives‘ and then on ‗Cube‘.
Step 3: Create a door using NURBS primitive cube.
Step 4: Create balconies using NURBS primitive cube and remove the top and backside.
Step 5: Press 5 to solidify and render.
OUTPUT
Four View
Experiment-3
AIM:-To bounce a ball using Animation.
STEPS:-
Step 1: Select ‗Animation‘ from main menu bar.

Step 2: Click ‗Create‘ on Maya title bar and then click on ‗Polygon‘s primitives‘ and then click
on ‗Sphere‘.
Step 3: Click ‗Move‘ tool to move the ball to position in a frame.
Step 4: Fix the position of the ball in a frame by pressing the ‗Set‘ key(Shortcut-S).
Step 5: Move to the next frame and set another position of the ball using Set key.
Step 6: Click ‗Play‘ to view the moving ball.
OUTPUT
Four View

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LAB MANUAL

Maharaja Agrasen Institute of Technology,

1. Introduction to the lab

2. Lab requirements (details of H/W & S/W to be used)

3. List of experiments (as per syllabus prescribed by G.G.S.I.P.U)

4. List of experiments (beyond the syllabus prescribed by G.G.S.I.P.U)

5. Format of lab record to be prepared by the students.

6. Marking scheme for the practical exam

Software requirements: Turbo C++ or Turbo C compiler, MAYA

Operating System: Windows XP (SP2)

2 GB hard disk space

Qualified hardware-accelerated OpenGL graphics card

COMPUTER GRAPHICS & MULTIMEDIA LAB

Paper Code: ETCS-257 L T C

1. Study of Fundamental Graphics Functions.

2. Implementation of Line drawing algorithms: DDA Algorithm, Bresenham's Algorithm

3. Implementation of Circle drawing algorithms: Bresenham's Algorithm, Mid-Point

4. Programs on 2D and 3D transformations

5. Write a program to implement Cohen Sutherland line clipping algorithm

6. Write a program to draw Bezier curve.

COMPUTER GRAPHICS & MULTIMEDIA LAB

1. To Study various in build graphics functions in C library.

NAME OF THE LAB

Faculty name Student name Font

Maharaja Agrasen Institute of Technology, PSP Area,

COMPUTER GRAPHICS & MULTIMEDIA LAB

PAPER CODE : ETCS - 257

Name of the student :

University Roll No. :

a) Experiments according to the list provided by GGSIPU

Exp. no Experiment Name Date of Date of Remarks Marks

 Internal Practical Exam

INTERNAL PRACTICAL EXAM

It is taken by the concerned lecturer of the batch.

MARKING SCHEME FOR THIS EXAM IS:

Division of 40 marks is as follows

 Performing program in each turn of the lab

MARKING SCHEME FOR THIS EXAM IS:

Division of 60 marks is as follows

a. Sheet filled by the student: 20

 Internal marks + External marks = Total marks given to the students

 Experiments given to perform can be from any section of the lab.

EXPECTED VIVA QUESTIONS

4) ARC, CIRCLE, PIESLICE

5) ELLIPSE, FILLELIPSE, SECTOR

8) LINE, LINEREL, LINETO

Bresenham’s algorithm for line drawing.

A C++ program to draw a circle using Bresenham's Circle Algorithm.

PROGRAM TO ROTATE A TRIANGLE ABOUT ORIGIN.

printf"\n Enter 2nd coordinates of triangle:";

printf"\n Enter 3rd coordinates of triangle:";

printf"\n Enter 2nd coordinates of triangle:";

printf"\n Enter 3rd coordinates of triangle:";

printf"\n Enter translatio factors :\n";

printf"Enter the coordinates of point around which rotation is done");

printf"Enter the angle for rotation");

printf"Point after rotation is:";

printf"Enter the angle for rotation");