3. Header file for Graphics Functions
graphics.h header file is included which contain
functions to draw different shapes, display text in
different fonts, change colors, etc.
4. initgraph(); Used to initialize graphics mode.
Syntax: void initgraph ( int *driver, int *mode, char *path);
Initializing Graphical mode
graphresult(); It returns error code if occur in initializing
graphics.
Syntax: int graphresult (void);
grapherrormsg(); It returns corresponding error message
of error code.
Syntax: char grapherrormsg (int errorcode);
5. outtext(); Used to print string in graphic mode at
current position.
Syntax: void outtext (char textstring);
Displaying Text on screen
outtextxy(); Used to print string in graphic mode at
given coordinates.
Syntax: void outtextxy (int x, int y, char textstring);
8. setcolor(); It sets the color of lines.
Syntax: void setcolor (int COLOR);
Coloring
setbkcolor(); It sets the background color of screen.
Syntax: void setbkcolor (int COLOR);
9. Table of Colors
COLOR Name Value
BLACK 0
BLUE 1
GREEN 2
CYAN 3
RED 4
MAGENTA 5
BROWN 6
LIGHTGRAY 7
DARKGRAY 8
LIGHTBLUE 9
LIGHTGREEN 10
LIGHTCYAN 11
LIGHTRED 12
LIGHTMAGENTA 13
YELLOW 14
WHITE 15
COLOR Name Value
10. rectangle(); It draws an empty rectangle.
Syntax: void rectangle (int x, int y, int x+width, int y+height );
Drawing empty/solid Rectangles
bar();
It draws a filled rectangle.Syntax: void bar (int x, int y, int x+width, int y+height );
It draws a filled rectangle.
11. setfillstyle(); It sets current fill pattern and fill color.
Syntax: void setfillstyle (int fillpattern, int COLOR);
Fill styling
Fill Patterns:
12. setlinestyle(); It sets current style of lines.
Syntax: void setlinestyle (int linestyle, unsigned upattern, int thickness);
Line styling
Line Styles:
13. cleardevice(); It erases the screen and move CP to origin.
Syntax: void cleardevice (void);
Some more functions
closegraph();
Syntax: void closegraph (void);
It closes the graphics mode and returns
the screen to text mode.
15. Mouse Programming
Mouse programming in C is done by interacting
with registers and interrupts. dos.h also include
functions for Mouse Programming.
16. Interrupt: Signal sent by a hardware for immediate
processing is known as interrupt.
Interacting with interrupts
Register: Small data holding place of Processor.
int86();
Syntax: int int86 (int interrupt, union REGS *inreg, union REGS *outreg);
This function is used to interact with
interrupts using registers.
The interrupt for Mouse is: 0x33
17. Union Data Type
union is a special data type in C which allows to
store different data types in the same memory
location.
Example:
union Data {
int I; float f;
} data;
18. First Parameter of int86() function is 0x33 to interact with Mouse.
Second Parameter is address of a union REGS type integer which is
used to input data for interrupt.
Third Parameter is also address of a union REGS type integer in
which output by interrupt is stored.
Both union REGS type variables are declared before main()
function. Like:
Using int86();
union REGS input, output;
19. ax, bx, cx and dx register are used to input and output data.
Syntax to input and out data from registers is:
Using int86();
// To send data to register
input.x.ax = 0;
int86( 0x33, &input, &output);
// Now output.x.ax is storing out from interrupt
20. Input Description Output
AX = 0 Get mouse
status
If AX = 0, Mouse
support isn’t
available
AX = 1
Show Mouse
Pointer
__
AX = 3 Get cursor
position
CX = X axis,
DX = Y axis
AX = 3 Which Mouse
button is pressed
BX = 0 No
BX = 1 Left
BX = 2 Right
