Transcript BGI graphics library

BGI graphics library
And Visual Studio
Layout of graphics window
X  increasing
0, 0
Y
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Prolog required for every
graphics program
#include “graphics.h” - same place as other includes
AND inside main()
start graphics code with
initwindow (x, y); // x is the number of pixels horizontally
// and y is the number of pixels vertically
or
initwindow (x, y, string); // where string is the title to go in
// the title bar of the graphics window
Required at end of program
closegraph();
usually right before return 0;
if you want to pause the graphics window
you can use
getch();
this is a function that will get a character from
the keyboard and discard it
Functions
x = getmaxx();
 y = getmaxy();
return the highest x value and y value possible
in the current graphics mode
These can be useful if you want something
centered in the window
putpixel (x/2, y/2, RED); would put a tiny red
dot in the middle of the window

To pause the program

getch();
strictly this does return the character that
was pressed on the keyboard, but for this use
we do not care what character was pressed.
So the function can be called as a “void”
function, i.e. on a line by itself
More Functions - Color
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void setcolor (int color); color used to draw
with
void setfillpattern (SOLID_FILL, BLUE); will
cause any 'filled' or 'bar' calls after that to fill
in solidly with blue
BLUE, GREEN, CYAN, RED and so on are
named constants (actually integers) that you
can use as color arguments; SOLID_FILL,
LINE_FILL, SLASH_FILL are the same for fill
patterns
More functions
void line (int x1, int y1, int x2, int y2 ); draws a
line from (x1, y1) to (x2, y2)
line (25, 50, 35, 50); // horizontal
 void rectangle (int left, int top, int right, int
bottom);
rectangle (150, 200, 400, 350);
// a box that is 250 pixels wide and 150 tall
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Another function

outtextxy(x, y, "This is a test.");
(x,y) is where the text will start on the screen
if you want to pass a string variable to this
function, you must use
outtextxy (x, y, const_cast<char*>(str.c_str()));
where str is the name of the string variable