CGLab File for college

8/18/2019 CGLab File for college

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Computer Graphics Lab.File


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SS.No

Name of Experiment Date Signature of

Faculty


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List of Experiments

1) Study of basic graphics functions defined in “graphics.h”.

2) WAP to draw a line through Bresenha!sAlgorith.

") Write a progra to draw a line using ##A algorith.

$) Write a progra to draw a circle using Bresenha!salgorith.

%) Write a progra to rotate a &ircle around anarbitrary point

') Write a progra to ipleent reflection of a point(line.

) Write a progra to scale an ob*ect about theorigin.


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EXPERIMENT NO 1

BASIC GRAPICS F!NC"I#NS !SE$

%& INI"GRAP• Initializes the graphics system.

$eclaration

• Void far initgraph(int far *graphdriver)

Remar's

• To start the graphic system, you must first call initgraph.

• Initgraph initializes the graphic system by loading a graphics driver from dis (or

validating a registered driver) then putting the system into graphics mode.

• Initgraph also resets all graphics settings (color, palette, current position, vie!port, etc) to

their defaults then resets graph.

(& GE"PI)EL* P!"PI)EL

• "etpi#el gets the color of a specified pi#el.

• $utpi#el places a pi#el at a specified point.

$eclaration

• %nsigned far getpi#el(int #, int y)

• Void far putpi#el(int #, int y, int color)

Remar's

• "etpi#el gets the color of the pi#el located at (#,y)&

• $utpi#el plots a point in the color defined at (#, y).


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Return +alue

• "etpi#el returns the color of the given pi#el.

• $utpi#el does not return.

,& CL#SE GRAP

• 'huts do!n the graphic system.

$eclaration

• Void far closegraph(void)&

Remar's

• lose graph deallocates all memory allocated by the graphic system.

• It then restores the screen to the mode it !as in before you called initgraph.

Return +alue

• )one.

-& ARC* CIRCLE* PIESLICE

• arc dra!s a circular arc.

• ircle dra!s a circle

• $ieslice dra!s and fills a circular pieslice

$eclaration

• Void far arc(int #, int y, int stangle, int endangle, int radius)&

•

Void far circle(int #, int y, int radius)&

• Void far pieslice(int #, int y, int stangle, int endangle, int radius)&

Remar's

• rc dra!s a circular arc in the current dra!ing color


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• ircle dra!s a circle in the current dra!ing color

• $ieslice dra!s a pieslice in the current dra!ing color, then fills it using the current fill

pattern and fill color.

& ELLIPSE* FILLELIPSE* SEC"#R

• +llipse dra!s an elliptical arc.

• illellipse dra!s and fills ellipse.

• 'ector dra!s and fills an elliptical pie slice.

$eclaration

• Void far ellipse(int #, int y, int stangle, int endangle, int #radius, int yradius)

• Void far fillellipse(int #, int y, int #radius, int yradius)

• Void farsectoe(int #, int y, int stangle, int endangle, int #radius, int yradius)

Remar's

• +llipse dra!s an elliptical arc in the current dra!ing color.

• illellipse dra!s an elliptical arc in the current dra!ing color and than fills it !ith fill color

and fill pattern.

•

'ector dra!s an elliptical pie slice in the current dra!ing color and than fills it using the

pattern and color defined by setfillstyle or setfillpattern.

/& FL##$FILL

• lood-fills a bounded region.

$eclaration

•

Void far floodfill(int #, int y, int border)

Remar's

• loodfills an enclosed area on bitmap device.

• The area bounded by the color border is flooded !ith the current fill pattern and fill color.


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• (#,y) is a seed point/

If the seed is !ithin an enclosed area, the inside !ill be filled.

If the seed is outside the enclosed area, the e#terior !ill be filled.

• %se fillpoly instead of floodfill !herever possible so you can maintain code compatibility

!ith future versions.

• loodfill doesnot !or !ith the I01-2345 driver.

Return +alue

• If an error occurs !hile flooding a region, graph result returns 647.

0& GE"C#L#R* SE"C#L#R

• "etcolor returns the current dra!ing color.

• 'etcolor returns the current dra!ing color.

$eclaration

• Int far getcolor(void)&

• Void far setcolor(int color)

Remar's

• "etcolor returns the current dra!ing color.

• 'etcolor sets the current dra!ing color to color, !hich can range from 8 to getma#color.

• To set a dra!ing color !ith setcolor , you can pass either the color number or the

e9uivalent color name.

1& LINE*LINEREL*LINE"#

• :ine dra!s a line bet!een t!o specified pints.

• ;nerel dra!s a line relative distance from current position($).

• :inrto dra!s a line from the current position ($) to(#,y).

$eclaration


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• Void far lineto(int #, int y)

Remar's

• :ine dra!s a line from (#4, y4) to (#


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EXPERIMENT 2

BRESENHAM’S ALGOR!HM FOR LNE DRA"NG#

4. 'tart.

y4.

@. alculate d#>#y(


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"A$ !O DRA" A LNE %SNG BRESENHAM’S ALGOR!

GincludeEstdio.hH

GincludeEconio.hHGincludeEgraphics.hH

void main()

int #,y,#4,y4,#


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p>#F4&

y>yF4&

p>pF


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#!"P!"


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EXPERIMENT NO 3.

ALGOR!HM !O DRA" A LNE %SNG DDA ALGOR!HM

4. 'tart.

y4.

@. alculate d#>#yabs(d#).

2.

;ther!ise s> abs(dy).

D. Then #i>d#Os and yi>dyOs.

48. 'tart from >8 and continuing till Es,the points !ill be

i. #>#F#i.

ii. y>yFyi.

44. $lace pi#els using putpi#el at points (#,y) in specified colour.

4


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"A$ !O DRA" A LNE %SNG DDA ALGOR!HM

GincludeEstdio.hH

GincludeEconio.hH

GincludeEgraphics.hH

void main()

int #,y,#4,##yabs(d#)&

else

s>abs(dy)&

#i>d#Os&

yi>dyOs&

#>#4&

y>y4&

putpi#el(#,y,B)&

for(>8&Es&FF)


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#>#F#i&

y>yFyi&

putpi#el(#,y,B)&

N

getch()&

closegraph()&

N


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#!"P!"


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EXPERIMENT 4.

BRESENHAM’S ALGOR!HM !O DRA" A &R&LE#

4. 'tart.

=+T+T,gmode.?. Initialise the graphic mode !ith the path location in T folder.

5. Input the radius of the circle r.

3. :oad #-8,y>r,initial decision parameter p>4-r.so the first point is (8,r).

@. Cepeat 'tep B !hile (#Ey) and increment #-value simultaneously.

B. If (pH8),do p>pFpF


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"A$ !O DRA" A &R&LE %SNG BRESENHAM’SALGOR!HM.

GincludeEstdio.hH

GincludeEconio.hH


void circlepoints(int,int)&

void main()

int #,y,p,r&

int gdriver>=+T+T,gmode&

initgraph(Jgdriver,Jgmode,KALLtcLLbgiAK)&

clrscr()&

printf(Kenter the radiusK)&

scanf(KMdK,Jr)&

#>8&y>r&p>4-r&

!hile(#Ey)

#FF&

if(pH8)

p>pFpF


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putpi#el(#F?88,yF?88,2)&

putpi#el(#F?88,-yF?88,2)&

putpi#el(-#F?88,yF?88,2)&

putpi#el(-#F?88,-yF?88,2)&

putpi#el(yF?88,#F?88,2)&

putpi#el(yF?88,-#F?88,2)&

putpi#el(-yF?88,#F?88,2)&

putpi#el(-yF?88,-#F?88,2)&

N


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#!"P!"


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EXPERIMENT 5.

PR#GRA3 "# REFLEC" A "RIANGLE

GincludeEiostream.hH

GincludeEconio.hH


GincludeEprocess.hH

GincludeEmath.hH

void main()

clrscr()&

int graphdriver>=+T+T,graphmode&

initgraph(Jgraphdriver,Jgraphmode,K...LLbgiK)&

int #,y,#4,aP?QP?Q&

double bP?QP?Q,cP?QP?Q&

coutEEKLn +nter Ist coordinates of triangleAK&

cinHHaP8QP8QHHaP4QP8Q&

coutEEKLn +nter


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line(aP8QP8Q,aP4QP8Q,aP8QP4Q,aP4QP4Q)&

line(aP8QP4Q,aP4QP4Q,aP8QP


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case ?A bP8QP8Q>@58-aP8QP8Q&

bP8QP4Q>@58-aP8QP4Q&

bP8QP@58-aP8QPaP4QP8Q&

bP4QP4Q>aP4QP4Q&

bP4QPaP4QP


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#!"P!"


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EXPERIMENT 6.

PR#GRA3 "# SCALE "E "RIANGLE


GincludeEconio.hH

GincludeEgraphics.hH;

void main()

int gd>=+T+T,gm&

initgraph(Jgd, Jgm,KK)&

cleardevice()&

int #4,y4,#


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ysy*ys#*#?-#5&

y?>sy*y?-y5&

polyP8Q>#4&

polyP4Q>y4&

polyP#y#?&

polyP3Q>y?&

polyP@Q>#4&

polyPBQ>y4&

getch()&

cleardevice()&

dra!poly(5,poly)&

getch()&

closegraph()&

N


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#!"P!"


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EXPERIMENT NO 7.

"A$ !O RO!A!E A !RANGLE ABO%! ORGN.


GincludeEconio.hH

GincludeEgraphics.hHGincludeEprocess.hH

GincludeEmath.hH

void main()

clrscr()&

int graphdriver>=+T+T,graphmode&

initgraph(Jgraphdriver,Jgraphmode,K...LLbgiK)&

int #,y,#4,aP?QP?Q&

double bP?QP?Q,cP?QP?Q&

coutEEKLn +nter Ist coordinates of triangleAK&

cinHHaP8QP8QHHaP4QP8Q&

coutEEKLn +nter


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bP8QP8Q>bP4QP4Q>cos((#*?.45)O428)&

bP8QP4Q>-sin((#*?.45)O428)&

bP4QP8Q>sin((#*?.45)O428)&

bP8&iE?&iFF)

for(int R>8&RE?&RFF)

cPiQPRQ>8&

for (int >8& E?&FF)

cPiQPRQF>aPiQPQ*bPQPRQ&

N

#4>(cPiQPRQF8.3)&

aPiQPRQ>#4&

N

N

coutEEKLn Triangle after rotation isALnK &

line(aP8QP8Q,aP4QP8Q,aP8QP4Q,aP4QP4Q)&

line(aP8QP4Q,aP4QP4Q,aP8QP


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#!"P!"


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CGLab File for college